From patchwork Thu Apr 8 18:28:26 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 12192175 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.2 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0787CC43603 for ; Thu, 8 Apr 2021 18:28:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C62E360C3E for ; Thu, 8 Apr 2021 18:28:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232804AbhDHS3A (ORCPT ); Thu, 8 Apr 2021 14:29:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48632 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232814AbhDHS27 (ORCPT ); Thu, 8 Apr 2021 14:28:59 -0400 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 344AAC061761 for ; Thu, 8 Apr 2021 11:28:48 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id k199so135482ybf.0 for ; Thu, 08 Apr 2021 11:28:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc:content-transfer-encoding; bh=iMDwFdVThvrdGx8QBp6Uu53WCJMJICP2P0osGdiAgo0=; b=BCUTgd4fnzYrB2C0Vdjttak22/XtoFXlio2+oftsFMRUAV6TMghf40ozthtJjSMF5h twckV5hRFX0JucfTtwhFSYt50FiSasTsXW41J+b1MtDbFvertOk0ZfTW/ZQcaIoTSxsG YjA1iuP9F6DcMz7u0mjnahpvg3ga6nHrA2h9G6HH7uGivA1oQcgyc9ag3mkAlLtidtxG gAMVsxEzpgYA7ZnX8nllumjsf3j9oASCK0W7TGeBP+GP8DdOTJqdfrL8ZOMoKMMZWeo8 FiueK6uw3iNzLriOxz4Zhj9S8tN0e0dt6zdBkOfkK1cuyESjJdYQkTG722NOzXaNwf0c 7/Gw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc:content-transfer-encoding; bh=iMDwFdVThvrdGx8QBp6Uu53WCJMJICP2P0osGdiAgo0=; b=gHUKc4ONrPJCNmunlU/vz/KLhpV28dx/P415WkmFCZoAGhu4rmrfWdtht2X8W/Uprz szpZqwlamI3mRrEnudfg7WrEtM9vXCuRTU8j2L4aXBohqiz8UrLwZaDWGUwnJuoK/wDS DTdy5bVmYkp8E2ssxbjmN89nsYSVWZqHwD8K8+hxhbPHstXG1KRLbEkJtX7n3u2HLAfX Srjc/aUxz+0mNv88sDVsf/3ylFGvc8YFSGm2zIxlxXNv2g7hcjPxK+eNETairwceoqxI X9nVxLsgK36LbmgCBHE4R3+HB1lxIQ841R2JBJKAJf2MYycOiTsYfslO2UYvmTYU+QNt rwBg== X-Gm-Message-State: AOAM532foEnNe3JCWWTa3oZBbuSGjW04Z/0n+QXDqeJ9pYe2b/+bHz0j rdEXVWazzBaxd5D3jY+Jq+L47fqtpw2xKtseOkA= X-Google-Smtp-Source: ABdhPJyzB19ImNMYmWAZ0XojX/sEv77hXRxItsKhfTCg4MKza3rj3inC3/LXzRuauW27+h+vHHvLRdkfEigrUH+hEcA= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:3560:8505:40a2:e021]) (user=samitolvanen job=sendgmr) by 2002:a25:d6d4:: with SMTP id n203mr13662320ybg.177.1617906527457; Thu, 08 Apr 2021 11:28:47 -0700 (PDT) Date: Thu, 8 Apr 2021 11:28:26 -0700 In-Reply-To: <20210408182843.1754385-1-samitolvanen@google.com> Message-Id: <20210408182843.1754385-2-samitolvanen@google.com> Mime-Version: 1.0 References: <20210408182843.1754385-1-samitolvanen@google.com> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog Subject: [PATCH v6 01/18] add support for Clang CFI From: Sami Tolvanen To: Kees Cook Cc: Nathan Chancellor , Nick Desaulniers , Masahiro Yamada , Will Deacon , Jessica Yu , Arnd Bergmann , Tejun Heo , "Paul E. McKenney" , Christoph Hellwig , Peter Zijlstra , Sedat Dilek , Mark Rutland , Catalin Marinas , bpf@vger.kernel.org, linux-hardening@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org This change adds support for Clang’s forward-edge Control Flow Integrity (CFI) checking. With CONFIG_CFI_CLANG, the compiler injects a runtime check before each indirect function call to ensure the target is a valid function with the correct static type. This restricts possible call targets and makes it more difficult for an attacker to exploit bugs that allow the modification of stored function pointers. For more details, see: https://clang.llvm.org/docs/ControlFlowIntegrity.html Clang requires CONFIG_LTO_CLANG to be enabled with CFI to gain visibility to possible call targets. Kernel modules are supported with Clang’s cross-DSO CFI mode, which allows checking between independently compiled components. With CFI enabled, the compiler injects a __cfi_check() function into the kernel and each module for validating local call targets. For cross-module calls that cannot be validated locally, the compiler calls the global __cfi_slowpath_diag() function, which determines the target module and calls the correct __cfi_check() function. This patch includes a slowpath implementation that uses __module_address() to resolve call targets, and with CONFIG_CFI_CLANG_SHADOW enabled, a shadow map that speeds up module look-ups by ~3x. Clang implements indirect call checking using jump tables and offers two methods of generating them. With canonical jump tables, the compiler renames each address-taken function to .cfi and points the original symbol to a jump table entry, which passes __cfi_check() validation. This isn’t compatible with stand-alone assembly code, which the compiler doesn’t instrument, and would result in indirect calls to assembly code to fail. Therefore, we default to using non-canonical jump tables instead, where the compiler generates a local jump table entry .cfi_jt for each address-taken function, and replaces all references to the function with the address of the jump table entry. Note that because non-canonical jump table addresses are local to each component, they break cross-module function address equality. Specifically, the address of a global function will be different in each module, as it's replaced with the address of a local jump table entry. If this address is passed to a different module, it won’t match the address of the same function taken there. This may break code that relies on comparing addresses passed from other components. CFI checking can be disabled in a function with the __nocfi attribute. Additionally, CFI can be disabled for an entire compilation unit by filtering out CC_FLAGS_CFI. By default, CFI failures result in a kernel panic to stop a potential exploit. CONFIG_CFI_PERMISSIVE enables a permissive mode, where the kernel prints out a rate-limited warning instead, and allows execution to continue. This option is helpful for locating type mismatches, but should only be enabled during development. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Tested-by: Nathan Chancellor --- Makefile | 17 ++ arch/Kconfig | 45 ++++ include/asm-generic/bug.h | 16 ++ include/asm-generic/vmlinux.lds.h | 20 +- include/linux/cfi.h | 41 ++++ include/linux/compiler-clang.h | 2 + include/linux/compiler_types.h | 4 + include/linux/init.h | 2 +- include/linux/module.h | 13 +- init/Kconfig | 2 +- kernel/Makefile | 4 + kernel/cfi.c | 329 ++++++++++++++++++++++++++++++ kernel/module.c | 43 ++++ scripts/Makefile.modfinal | 2 +- 14 files changed, 534 insertions(+), 6 deletions(-) create mode 100644 include/linux/cfi.h create mode 100644 kernel/cfi.c diff --git a/Makefile b/Makefile index cc77fd45ca64..427f75249d5e 100644 --- a/Makefile +++ b/Makefile @@ -920,6 +920,23 @@ KBUILD_AFLAGS += -fno-lto export CC_FLAGS_LTO endif +ifdef CONFIG_CFI_CLANG +CC_FLAGS_CFI := -fsanitize=cfi \ + -fsanitize-cfi-cross-dso \ + -fno-sanitize-cfi-canonical-jump-tables \ + -fno-sanitize-trap=cfi \ + -fno-sanitize-blacklist + +ifdef CONFIG_CFI_PERMISSIVE +CC_FLAGS_CFI += -fsanitize-recover=cfi +endif + +# If LTO flags are filtered out, we must also filter out CFI. +CC_FLAGS_LTO += $(CC_FLAGS_CFI) +KBUILD_CFLAGS += $(CC_FLAGS_CFI) +export CC_FLAGS_CFI +endif + ifdef CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_32B KBUILD_CFLAGS += -falign-functions=32 endif diff --git a/arch/Kconfig b/arch/Kconfig index ecfd3520b676..f6a85ba6cba2 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -692,6 +692,51 @@ config LTO_CLANG_THIN If unsure, say Y. endchoice +config ARCH_SUPPORTS_CFI_CLANG + bool + help + An architecture should select this option if it can support Clang's + Control-Flow Integrity (CFI) checking. + +config CFI_CLANG + bool "Use Clang's Control Flow Integrity (CFI)" + depends on LTO_CLANG && ARCH_SUPPORTS_CFI_CLANG + # Clang >= 12: + # - https://bugs.llvm.org/show_bug.cgi?id=46258 + # - https://bugs.llvm.org/show_bug.cgi?id=47479 + depends on CLANG_VERSION >= 120000 + select KALLSYMS + help + This option enables Clang’s forward-edge Control Flow Integrity + (CFI) checking, where the compiler injects a runtime check to each + indirect function call to ensure the target is a valid function with + the correct static type. This restricts possible call targets and + makes it more difficult for an attacker to exploit bugs that allow + the modification of stored function pointers. More information can be + found from Clang's documentation: + + https://clang.llvm.org/docs/ControlFlowIntegrity.html + +config CFI_CLANG_SHADOW + bool "Use CFI shadow to speed up cross-module checks" + default y + depends on CFI_CLANG && MODULES + help + If you select this option, the kernel builds a fast look-up table of + CFI check functions in loaded modules to reduce performance overhead. + + If unsure, say Y. + +config CFI_PERMISSIVE + bool "Use CFI in permissive mode" + depends on CFI_CLANG + help + When selected, Control Flow Integrity (CFI) violations result in a + warning instead of a kernel panic. This option should only be used + for finding indirect call type mismatches during development. + + If unsure, say N. + config HAVE_ARCH_WITHIN_STACK_FRAMES bool help diff --git a/include/asm-generic/bug.h b/include/asm-generic/bug.h index 76a10e0dca9f..b402494883b6 100644 --- a/include/asm-generic/bug.h +++ b/include/asm-generic/bug.h @@ -241,6 +241,22 @@ void __warn(const char *file, int line, void *caller, unsigned taint, # define WARN_ON_SMP(x) ({0;}) #endif +/* + * WARN_ON_FUNCTION_MISMATCH() warns if a value doesn't match a + * function address, and can be useful for catching issues with + * callback functions, for example. + * + * With CONFIG_CFI_CLANG, the warning is disabled because the + * compiler replaces function addresses taken in C code with + * local jump table addresses, which breaks cross-module function + * address equality. + */ +#if defined(CONFIG_CFI_CLANG) && defined(CONFIG_MODULES) +# define WARN_ON_FUNCTION_MISMATCH(x, fn) ({ 0; }) +#else +# define WARN_ON_FUNCTION_MISMATCH(x, fn) WARN_ON_ONCE((x) != (fn)) +#endif + #endif /* __ASSEMBLY__ */ #endif diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 0331d5d49551..40a9c101565e 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -544,6 +544,22 @@ . = ALIGN((align)); \ __end_rodata = .; + +/* + * .text..L.cfi.jumptable.* contain Control-Flow Integrity (CFI) + * jump table entries. + */ +#ifdef CONFIG_CFI_CLANG +#define TEXT_CFI_JT \ + . = ALIGN(PMD_SIZE); \ + __cfi_jt_start = .; \ + *(.text..L.cfi.jumptable .text..L.cfi.jumptable.*) \ + . = ALIGN(PMD_SIZE); \ + __cfi_jt_end = .; +#else +#define TEXT_CFI_JT +#endif + /* * Non-instrumentable text section */ @@ -570,6 +586,7 @@ NOINSTR_TEXT \ *(.text..refcount) \ *(.ref.text) \ + TEXT_CFI_JT \ MEM_KEEP(init.text*) \ MEM_KEEP(exit.text*) \ @@ -974,7 +991,8 @@ * keep any .init_array.* sections. * https://bugs.llvm.org/show_bug.cgi?id=46478 */ -#if defined(CONFIG_GCOV_KERNEL) || defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KCSAN) +#if defined(CONFIG_GCOV_KERNEL) || defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KCSAN) || \ + defined(CONFIG_CFI_CLANG) # ifdef CONFIG_CONSTRUCTORS # define SANITIZER_DISCARDS \ *(.eh_frame) diff --git a/include/linux/cfi.h b/include/linux/cfi.h new file mode 100644 index 000000000000..879744aaa6e0 --- /dev/null +++ b/include/linux/cfi.h @@ -0,0 +1,41 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Clang Control Flow Integrity (CFI) support. + * + * Copyright (C) 2021 Google LLC + */ +#ifndef _LINUX_CFI_H +#define _LINUX_CFI_H + +#ifdef CONFIG_CFI_CLANG +typedef void (*cfi_check_fn)(uint64_t id, void *ptr, void *diag); + +/* Compiler-generated function in each module, and the kernel */ +extern void __cfi_check(uint64_t id, void *ptr, void *diag); + +/* + * Force the compiler to generate a CFI jump table entry for a function + * and store the jump table address to __cfi_jt_. + */ +#define __CFI_ADDRESSABLE(fn, __attr) \ + const void *__cfi_jt_ ## fn __visible __attr = (void *)&fn + +#ifdef CONFIG_CFI_CLANG_SHADOW + +extern void cfi_module_add(struct module *mod, unsigned long base_addr); +extern void cfi_module_remove(struct module *mod, unsigned long base_addr); + +#else + +static inline void cfi_module_add(struct module *mod, unsigned long base_addr) {} +static inline void cfi_module_remove(struct module *mod, unsigned long base_addr) {} + +#endif /* CONFIG_CFI_CLANG_SHADOW */ + +#else /* !CONFIG_CFI_CLANG */ + +#define __CFI_ADDRESSABLE(fn, __attr) + +#endif /* CONFIG_CFI_CLANG */ + +#endif /* _LINUX_CFI_H */ diff --git a/include/linux/compiler-clang.h b/include/linux/compiler-clang.h index d217c382b02d..6de9d0c9377e 100644 --- a/include/linux/compiler-clang.h +++ b/include/linux/compiler-clang.h @@ -61,3 +61,5 @@ #if __has_feature(shadow_call_stack) # define __noscs __attribute__((__no_sanitize__("shadow-call-stack"))) #endif + +#define __nocfi __attribute__((__no_sanitize__("cfi"))) diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h index e5dd5a4ae946..796935a37e37 100644 --- a/include/linux/compiler_types.h +++ b/include/linux/compiler_types.h @@ -242,6 +242,10 @@ struct ftrace_likely_data { # define __noscs #endif +#ifndef __nocfi +# define __nocfi +#endif + #ifndef asm_volatile_goto #define asm_volatile_goto(x...) asm goto(x) #endif diff --git a/include/linux/init.h b/include/linux/init.h index 31f54de58429..b3ea15348fbd 100644 --- a/include/linux/init.h +++ b/include/linux/init.h @@ -47,7 +47,7 @@ /* These are for everybody (although not all archs will actually discard it in modules) */ -#define __init __section(".init.text") __cold __latent_entropy __noinitretpoline +#define __init __section(".init.text") __cold __latent_entropy __noinitretpoline __nocfi #define __initdata __section(".init.data") #define __initconst __section(".init.rodata") #define __exitdata __section(".exit.data") diff --git a/include/linux/module.h b/include/linux/module.h index da4b6fbe8ebe..8100bb477d86 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -26,6 +26,7 @@ #include #include #include +#include #include #include @@ -128,13 +129,17 @@ extern void cleanup_module(void); #define module_init(initfn) \ static inline initcall_t __maybe_unused __inittest(void) \ { return initfn; } \ - int init_module(void) __copy(initfn) __attribute__((alias(#initfn))); + int init_module(void) __copy(initfn) \ + __attribute__((alias(#initfn))); \ + __CFI_ADDRESSABLE(init_module, __initdata); /* This is only required if you want to be unloadable. */ #define module_exit(exitfn) \ static inline exitcall_t __maybe_unused __exittest(void) \ { return exitfn; } \ - void cleanup_module(void) __copy(exitfn) __attribute__((alias(#exitfn))); + void cleanup_module(void) __copy(exitfn) \ + __attribute__((alias(#exitfn))); \ + __CFI_ADDRESSABLE(cleanup_module, __exitdata); #endif @@ -376,6 +381,10 @@ struct module { const s32 *crcs; unsigned int num_syms; +#ifdef CONFIG_CFI_CLANG + cfi_check_fn cfi_check; +#endif + /* Kernel parameters. */ #ifdef CONFIG_SYSFS struct mutex param_lock; diff --git a/init/Kconfig b/init/Kconfig index 5f5c776ef192..5babea38e346 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -2296,7 +2296,7 @@ endif # MODULES config MODULES_TREE_LOOKUP def_bool y - depends on PERF_EVENTS || TRACING + depends on PERF_EVENTS || TRACING || CFI_CLANG config INIT_ALL_POSSIBLE bool diff --git a/kernel/Makefile b/kernel/Makefile index 320f1f3941b7..e8a6715f38dc 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -41,6 +41,9 @@ KCSAN_SANITIZE_kcov.o := n UBSAN_SANITIZE_kcov.o := n CFLAGS_kcov.o := $(call cc-option, -fno-conserve-stack) -fno-stack-protector +# Don't instrument error handlers +CFLAGS_REMOVE_cfi.o := $(CC_FLAGS_CFI) + obj-y += sched/ obj-y += locking/ obj-y += power/ @@ -111,6 +114,7 @@ obj-$(CONFIG_BPF) += bpf/ obj-$(CONFIG_KCSAN) += kcsan/ obj-$(CONFIG_SHADOW_CALL_STACK) += scs.o obj-$(CONFIG_HAVE_STATIC_CALL_INLINE) += static_call.o +obj-$(CONFIG_CFI_CLANG) += cfi.o obj-$(CONFIG_PERF_EVENTS) += events/ diff --git a/kernel/cfi.c b/kernel/cfi.c new file mode 100644 index 000000000000..e17a56639766 --- /dev/null +++ b/kernel/cfi.c @@ -0,0 +1,329 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Clang Control Flow Integrity (CFI) error and slowpath handling. + * + * Copyright (C) 2021 Google LLC + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* Compiler-defined handler names */ +#ifdef CONFIG_CFI_PERMISSIVE +#define cfi_failure_handler __ubsan_handle_cfi_check_fail +#else +#define cfi_failure_handler __ubsan_handle_cfi_check_fail_abort +#endif + +static inline void handle_cfi_failure(void *ptr) +{ + if (IS_ENABLED(CONFIG_CFI_PERMISSIVE)) + WARN_RATELIMIT(1, "CFI failure (target: %pS):\n", ptr); + else + panic("CFI failure (target: %pS)\n", ptr); +} + +#ifdef CONFIG_MODULES +#ifdef CONFIG_CFI_CLANG_SHADOW +/* + * Index type. A 16-bit index can address at most (2^16)-2 pages (taking + * into account SHADOW_INVALID), i.e. ~256M with 4k pages. + */ +typedef u16 shadow_t; +#define SHADOW_INVALID ((shadow_t)~0UL) + +struct cfi_shadow { + /* Page index for the beginning of the shadow */ + unsigned long base; + /* An array of __cfi_check locations (as indices to the shadow) */ + shadow_t shadow[1]; +} __packed; + +/* + * The shadow covers ~128M from the beginning of the module region. If + * the region is larger, we fall back to __module_address for the rest. + */ +#define __SHADOW_RANGE (_UL(SZ_128M) >> PAGE_SHIFT) + +/* The in-memory size of struct cfi_shadow, always at least one page */ +#define __SHADOW_PAGES ((__SHADOW_RANGE * sizeof(shadow_t)) >> PAGE_SHIFT) +#define SHADOW_PAGES max(1UL, __SHADOW_PAGES) +#define SHADOW_SIZE (SHADOW_PAGES << PAGE_SHIFT) + +/* The actual size of the shadow array, minus metadata */ +#define SHADOW_ARR_SIZE (SHADOW_SIZE - offsetof(struct cfi_shadow, shadow)) +#define SHADOW_ARR_SLOTS (SHADOW_ARR_SIZE / sizeof(shadow_t)) + +static DEFINE_MUTEX(shadow_update_lock); +static struct cfi_shadow __rcu *cfi_shadow __read_mostly; + +/* Returns the index in the shadow for the given address */ +static inline int ptr_to_shadow(const struct cfi_shadow *s, unsigned long ptr) +{ + unsigned long index; + unsigned long page = ptr >> PAGE_SHIFT; + + if (unlikely(page < s->base)) + return -1; /* Outside of module area */ + + index = page - s->base; + + if (index >= SHADOW_ARR_SLOTS) + return -1; /* Cannot be addressed with shadow */ + + return (int)index; +} + +/* Returns the page address for an index in the shadow */ +static inline unsigned long shadow_to_ptr(const struct cfi_shadow *s, + int index) +{ + if (unlikely(index < 0 || index >= SHADOW_ARR_SLOTS)) + return 0; + + return (s->base + index) << PAGE_SHIFT; +} + +/* Returns the __cfi_check function address for the given shadow location */ +static inline unsigned long shadow_to_check_fn(const struct cfi_shadow *s, + int index) +{ + if (unlikely(index < 0 || index >= SHADOW_ARR_SLOTS)) + return 0; + + if (unlikely(s->shadow[index] == SHADOW_INVALID)) + return 0; + + /* __cfi_check is always page aligned */ + return (s->base + s->shadow[index]) << PAGE_SHIFT; +} + +static void prepare_next_shadow(const struct cfi_shadow __rcu *prev, + struct cfi_shadow *next) +{ + int i, index, check; + + /* Mark everything invalid */ + memset(next->shadow, 0xFF, SHADOW_ARR_SIZE); + + if (!prev) + return; /* No previous shadow */ + + /* If the base address didn't change, an update is not needed */ + if (prev->base == next->base) { + memcpy(next->shadow, prev->shadow, SHADOW_ARR_SIZE); + return; + } + + /* Convert the previous shadow to the new address range */ + for (i = 0; i < SHADOW_ARR_SLOTS; ++i) { + if (prev->shadow[i] == SHADOW_INVALID) + continue; + + index = ptr_to_shadow(next, shadow_to_ptr(prev, i)); + if (index < 0) + continue; + + check = ptr_to_shadow(next, + shadow_to_check_fn(prev, prev->shadow[i])); + if (check < 0) + continue; + + next->shadow[index] = (shadow_t)check; + } +} + +static void add_module_to_shadow(struct cfi_shadow *s, struct module *mod, + unsigned long min_addr, unsigned long max_addr) +{ + int check_index; + unsigned long check = (unsigned long)mod->cfi_check; + unsigned long ptr; + + if (unlikely(!PAGE_ALIGNED(check))) { + pr_warn("cfi: not using shadow for module %s\n", mod->name); + return; + } + + check_index = ptr_to_shadow(s, check); + if (check_index < 0) + return; /* Module not addressable with shadow */ + + /* For each page, store the check function index in the shadow */ + for (ptr = min_addr; ptr <= max_addr; ptr += PAGE_SIZE) { + int index = ptr_to_shadow(s, ptr); + + if (index >= 0) { + /* Each page must only contain one module */ + WARN_ON_ONCE(s->shadow[index] != SHADOW_INVALID); + s->shadow[index] = (shadow_t)check_index; + } + } +} + +static void remove_module_from_shadow(struct cfi_shadow *s, struct module *mod, + unsigned long min_addr, unsigned long max_addr) +{ + unsigned long ptr; + + for (ptr = min_addr; ptr <= max_addr; ptr += PAGE_SIZE) { + int index = ptr_to_shadow(s, ptr); + + if (index >= 0) + s->shadow[index] = SHADOW_INVALID; + } +} + +typedef void (*update_shadow_fn)(struct cfi_shadow *, struct module *, + unsigned long min_addr, unsigned long max_addr); + +static void update_shadow(struct module *mod, unsigned long base_addr, + update_shadow_fn fn) +{ + struct cfi_shadow *prev; + struct cfi_shadow *next; + unsigned long min_addr, max_addr; + + next = vmalloc(SHADOW_SIZE); + + mutex_lock(&shadow_update_lock); + prev = rcu_dereference_protected(cfi_shadow, + mutex_is_locked(&shadow_update_lock)); + + if (next) { + next->base = base_addr >> PAGE_SHIFT; + prepare_next_shadow(prev, next); + + min_addr = (unsigned long)mod->core_layout.base; + max_addr = min_addr + mod->core_layout.text_size; + fn(next, mod, min_addr & PAGE_MASK, max_addr & PAGE_MASK); + + set_memory_ro((unsigned long)next, SHADOW_PAGES); + } + + rcu_assign_pointer(cfi_shadow, next); + mutex_unlock(&shadow_update_lock); + synchronize_rcu(); + + if (prev) { + set_memory_rw((unsigned long)prev, SHADOW_PAGES); + vfree(prev); + } +} + +void cfi_module_add(struct module *mod, unsigned long base_addr) +{ + update_shadow(mod, base_addr, add_module_to_shadow); +} + +void cfi_module_remove(struct module *mod, unsigned long base_addr) +{ + update_shadow(mod, base_addr, remove_module_from_shadow); +} + +static inline cfi_check_fn ptr_to_check_fn(const struct cfi_shadow __rcu *s, + unsigned long ptr) +{ + int index; + + if (unlikely(!s)) + return NULL; /* No shadow available */ + + index = ptr_to_shadow(s, ptr); + if (index < 0) + return NULL; /* Cannot be addressed with shadow */ + + return (cfi_check_fn)shadow_to_check_fn(s, index); +} + +static inline cfi_check_fn find_shadow_check_fn(unsigned long ptr) +{ + cfi_check_fn fn; + + rcu_read_lock_sched(); + fn = ptr_to_check_fn(rcu_dereference_sched(cfi_shadow), ptr); + rcu_read_unlock_sched(); + + return fn; +} + +#else /* !CONFIG_CFI_CLANG_SHADOW */ + +static inline cfi_check_fn find_shadow_check_fn(unsigned long ptr) +{ + return NULL; +} + +#endif /* CONFIG_CFI_CLANG_SHADOW */ + +static inline cfi_check_fn find_module_check_fn(unsigned long ptr) +{ + cfi_check_fn fn = NULL; + struct module *mod; + + rcu_read_lock_sched(); + mod = __module_address(ptr); + if (mod) + fn = mod->cfi_check; + rcu_read_unlock_sched(); + + return fn; +} + +static inline cfi_check_fn find_check_fn(unsigned long ptr) +{ + cfi_check_fn fn = NULL; + + if (is_kernel_text(ptr)) + return __cfi_check; + + /* + * Indirect call checks can happen when RCU is not watching. Both + * the shadow and __module_address use RCU, so we need to wake it + * up if necessary. + */ + RCU_NONIDLE({ + if (IS_ENABLED(CONFIG_CFI_CLANG_SHADOW)) + fn = find_shadow_check_fn(ptr); + + if (!fn) + fn = find_module_check_fn(ptr); + }); + + return fn; +} + +void __cfi_slowpath_diag(uint64_t id, void *ptr, void *diag) +{ + cfi_check_fn fn = find_check_fn((unsigned long)ptr); + + if (likely(fn)) + fn(id, ptr, diag); + else /* Don't allow unchecked modules */ + handle_cfi_failure(ptr); +} +EXPORT_SYMBOL(__cfi_slowpath_diag); + +#else /* !CONFIG_MODULES */ + +void __cfi_slowpath_diag(uint64_t id, void *ptr, void *diag) +{ + handle_cfi_failure(ptr); /* No modules */ +} +EXPORT_SYMBOL(__cfi_slowpath_diag); + +#endif /* CONFIG_MODULES */ + +void cfi_failure_handler(void *data, void *ptr, void *vtable) +{ + handle_cfi_failure(ptr); +} +EXPORT_SYMBOL(cfi_failure_handler); diff --git a/kernel/module.c b/kernel/module.c index 30479355ab85..20fb004e7d8d 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -2146,6 +2146,8 @@ void __weak module_arch_freeing_init(struct module *mod) { } +static void cfi_cleanup(struct module *mod); + /* Free a module, remove from lists, etc. */ static void free_module(struct module *mod) { @@ -2187,6 +2189,9 @@ static void free_module(struct module *mod) synchronize_rcu(); mutex_unlock(&module_mutex); + /* Clean up CFI for the module. */ + cfi_cleanup(mod); + /* This may be empty, but that's OK */ module_arch_freeing_init(mod); module_memfree(mod->init_layout.base); @@ -3866,6 +3871,8 @@ static int unknown_module_param_cb(char *param, char *val, const char *modname, return 0; } +static void cfi_init(struct module *mod); + /* * Allocate and load the module: note that size of section 0 is always * zero, and we rely on this for optional sections. @@ -3997,6 +4004,9 @@ static int load_module(struct load_info *info, const char __user *uargs, flush_module_icache(mod); + /* Setup CFI for the module. */ + cfi_init(mod); + /* Now copy in args */ mod->args = strndup_user(uargs, ~0UL >> 1); if (IS_ERR(mod->args)) { @@ -4070,6 +4080,7 @@ static int load_module(struct load_info *info, const char __user *uargs, synchronize_rcu(); kfree(mod->args); free_arch_cleanup: + cfi_cleanup(mod); module_arch_cleanup(mod); free_modinfo: free_modinfo(mod); @@ -4415,6 +4426,38 @@ int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *, #endif /* CONFIG_LIVEPATCH */ #endif /* CONFIG_KALLSYMS */ +static void cfi_init(struct module *mod) +{ +#ifdef CONFIG_CFI_CLANG + initcall_t *init; + exitcall_t *exit; + + rcu_read_lock_sched(); + mod->cfi_check = (cfi_check_fn) + find_kallsyms_symbol_value(mod, "__cfi_check"); + init = (initcall_t *) + find_kallsyms_symbol_value(mod, "__cfi_jt_init_module"); + exit = (exitcall_t *) + find_kallsyms_symbol_value(mod, "__cfi_jt_cleanup_module"); + rcu_read_unlock_sched(); + + /* Fix init/exit functions to point to the CFI jump table */ + if (init) + mod->init = *init; + if (exit) + mod->exit = *exit; + + cfi_module_add(mod, module_addr_min); +#endif +} + +static void cfi_cleanup(struct module *mod) +{ +#ifdef CONFIG_CFI_CLANG + cfi_module_remove(mod, module_addr_min); +#endif +} + /* Maximum number of characters written by module_flags() */ #define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4) diff --git a/scripts/Makefile.modfinal b/scripts/Makefile.modfinal index 735e11e9041b..dd87cea9fba7 100644 --- a/scripts/Makefile.modfinal +++ b/scripts/Makefile.modfinal @@ -23,7 +23,7 @@ modname = $(notdir $(@:.mod.o=)) part-of-module = y quiet_cmd_cc_o_c = CC [M] $@ - cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $< + cmd_cc_o_c = $(CC) $(filter-out $(CC_FLAGS_CFI), $(c_flags)) -c -o $@ $< %.mod.o: %.mod.c FORCE $(call if_changed_dep,cc_o_c) From patchwork Thu Apr 8 18:28:27 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 12192177 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E7FEAC433B4 for ; Thu, 8 Apr 2021 18:29:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B69FE61108 for ; Thu, 8 Apr 2021 18:29:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232855AbhDHS3E (ORCPT ); Thu, 8 Apr 2021 14:29:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48654 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232844AbhDHS3D (ORCPT ); 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bh=vvGV2K9qJKpfvq0cSok+JSuieXx8RQrlyRB1QstgZ+Y=; b=fRk7FiOKgg9NfTAP0EpXRVhVOlZInQqq+2VN7wQ545ddPZO/g6PfWT5yEwleP/Fykh wY4o+TDdyElj3oAoQAqRjjHpPTAnMB1Qv2upI+tWed4dgMUi6FWW7OzwOqkaaumVLeuL Eac7WDTnE5SjonK4UU0THYlhzXus1gX+/m+h6wA/GgsmLT4T+N67tptKfxdju9QNQq9g XKIda0ntozYNxNHkb8j1isKowpJtkntufwG925V9zsiOVe96t3JEkG8Wg2X2m4D05Yxt amB4QBYi8x2tiUayL4VKNx4B8DfSZn7IMW5l5Pd7eKup8VtTsLJVS+Dvlzd6BndRrOnY yv+Q== X-Gm-Message-State: AOAM533LkNZ4eoo7KA7NffTcRYlRU7ZiYGDekbRAFjmBwGlkwxxuxZkj 1IjsaYB8Lt6R3YidybMVtR7lswlY8otCGmZRbjs= X-Google-Smtp-Source: ABdhPJz0ehITxX9teec2gn0CPHcF57blIqcKaI1/CV63GE4M8xmJ3/25o/4dk/Km4yNV8f2TMjz9/jW33s2Uw/coxoc= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:3560:8505:40a2:e021]) (user=samitolvanen job=sendgmr) by 2002:a05:6214:1081:: with SMTP id o1mr9867133qvr.11.1617906529278; Thu, 08 Apr 2021 11:28:49 -0700 (PDT) Date: Thu, 8 Apr 2021 11:28:27 -0700 In-Reply-To: <20210408182843.1754385-1-samitolvanen@google.com> Message-Id: <20210408182843.1754385-3-samitolvanen@google.com> Mime-Version: 1.0 References: <20210408182843.1754385-1-samitolvanen@google.com> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog Subject: [PATCH v6 02/18] cfi: add __cficanonical From: Sami Tolvanen To: Kees Cook Cc: Nathan Chancellor , Nick Desaulniers , Masahiro Yamada , Will Deacon , Jessica Yu , Arnd Bergmann , Tejun Heo , "Paul E. McKenney" , Christoph Hellwig , Peter Zijlstra , Sedat Dilek , Mark Rutland , Catalin Marinas , bpf@vger.kernel.org, linux-hardening@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org With CONFIG_CFI_CLANG, the compiler replaces a function address taken in C code with the address of a local jump table entry, which passes runtime indirect call checks. However, the compiler won't replace addresses taken in assembly code, which will result in a CFI failure if we later jump to such an address in instrumented C code. The code generated for the non-canonical jump table looks this: : /* In C, &noncanonical points here */ jmp noncanonical ... : /* function body */ ... This change adds the __cficanonical attribute, which tells the compiler to use a canonical jump table for the function instead. This means the compiler will rename the actual function to .cfi and points the original symbol to the jump table entry instead: : /* jump table entry */ jmp canonical.cfi ... : /* function body */ ... As a result, the address taken in assembly, or other non-instrumented code always points to the jump table and therefore, can be used for indirect calls in instrumented code without tripping CFI checks. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Acked-by: Bjorn Helgaas # pci.h Tested-by: Nathan Chancellor --- include/linux/compiler-clang.h | 1 + include/linux/compiler_types.h | 4 ++++ include/linux/init.h | 4 ++-- include/linux/pci.h | 4 ++-- 4 files changed, 9 insertions(+), 4 deletions(-) diff --git a/include/linux/compiler-clang.h b/include/linux/compiler-clang.h index 6de9d0c9377e..adbe76b203e2 100644 --- a/include/linux/compiler-clang.h +++ b/include/linux/compiler-clang.h @@ -63,3 +63,4 @@ #endif #define __nocfi __attribute__((__no_sanitize__("cfi"))) +#define __cficanonical __attribute__((__cfi_canonical_jump_table__)) diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h index 796935a37e37..d29bda7f6ebd 100644 --- a/include/linux/compiler_types.h +++ b/include/linux/compiler_types.h @@ -246,6 +246,10 @@ struct ftrace_likely_data { # define __nocfi #endif +#ifndef __cficanonical +# define __cficanonical +#endif + #ifndef asm_volatile_goto #define asm_volatile_goto(x...) asm goto(x) #endif diff --git a/include/linux/init.h b/include/linux/init.h index b3ea15348fbd..045ad1650ed1 100644 --- a/include/linux/init.h +++ b/include/linux/init.h @@ -220,8 +220,8 @@ extern bool initcall_debug; __initcall_name(initstub, __iid, id) #define __define_initcall_stub(__stub, fn) \ - int __init __stub(void); \ - int __init __stub(void) \ + int __init __cficanonical __stub(void); \ + int __init __cficanonical __stub(void) \ { \ return fn(); \ } \ diff --git a/include/linux/pci.h b/include/linux/pci.h index 86c799c97b77..39684b72db91 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1944,8 +1944,8 @@ enum pci_fixup_pass { #ifdef CONFIG_LTO_CLANG #define __DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class, \ class_shift, hook, stub) \ - void stub(struct pci_dev *dev); \ - void stub(struct pci_dev *dev) \ + void __cficanonical stub(struct pci_dev *dev); \ + void __cficanonical stub(struct pci_dev *dev) \ { \ hook(dev); \ } \ From patchwork Thu Apr 8 18:28:28 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 12192179 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.2 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 31DA0C43461 for ; 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Thu, 08 Apr 2021 11:28:51 -0700 (PDT) Date: Thu, 8 Apr 2021 11:28:28 -0700 In-Reply-To: <20210408182843.1754385-1-samitolvanen@google.com> Message-Id: <20210408182843.1754385-4-samitolvanen@google.com> Mime-Version: 1.0 References: <20210408182843.1754385-1-samitolvanen@google.com> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog Subject: [PATCH v6 03/18] mm: add generic function_nocfi macro From: Sami Tolvanen To: Kees Cook Cc: Nathan Chancellor , Nick Desaulniers , Masahiro Yamada , Will Deacon , Jessica Yu , Arnd Bergmann , Tejun Heo , "Paul E. McKenney" , Christoph Hellwig , Peter Zijlstra , Sedat Dilek , Mark Rutland , Catalin Marinas , bpf@vger.kernel.org, linux-hardening@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org With CONFIG_CFI_CLANG, the compiler replaces function addresses in instrumented C code with jump table addresses. This means that __pa_symbol(function) returns the physical address of the jump table entry instead of the actual function, which may not work as the jump table code will immediately jump to a virtual address that may not be mapped. To avoid this address space confusion, this change adds a generic definition for function_nocfi(), which architectures that support CFI can override. The typical implementation of would use inline assembly to take the function address, which avoids compiler instrumentation. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Acked-by: Mark Rutland Tested-by: Nathan Chancellor --- include/linux/mm.h | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/include/linux/mm.h b/include/linux/mm.h index 8ba434287387..22cce9c7dd05 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -124,6 +124,16 @@ extern int mmap_rnd_compat_bits __read_mostly; #define lm_alias(x) __va(__pa_symbol(x)) #endif +/* + * With CONFIG_CFI_CLANG, the compiler replaces function addresses in + * instrumented C code with jump table addresses. Architectures that + * support CFI can define this macro to return the actual function address + * when needed. + */ +#ifndef function_nocfi +#define function_nocfi(x) (x) +#endif + /* * To prevent common memory management code establishing * a zero page mapping on a read fault. From patchwork Thu Apr 8 18:28:29 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 12192181 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.2 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F155AC43461 for ; Thu, 8 Apr 2021 18:29:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D089660C3E for ; Thu, 8 Apr 2021 18:29:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232926AbhDHS3W (ORCPT ); Thu, 8 Apr 2021 14:29:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48692 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232877AbhDHS3H (ORCPT ); Thu, 8 Apr 2021 14:29:07 -0400 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 25765C0613DA for ; Thu, 8 Apr 2021 11:28:54 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id k15so2898775ybh.6 for ; Thu, 08 Apr 2021 11:28:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=eRIdrbJ2jhHVLL9Tut/j9YYL8eIOqR89a+xPlg5BO0U=; b=nmyke+h8npDMiaqZwmNe2cMGG5hnU/u86z+9PT3d46wvKA7EcCFmI0rQdqzR05Y94d x+FoWT2ztku/VLu13xl6nOzxWcgAQBZNzaVQoRT/BZKY/QCn5viNJODflkqOHL2h8bIc aXPxyU21LsZKarOM3mV+jnfOkvN12Im/BNNAstmefU7NUVKXda8sDV56EdzQGZkRH6HI Ge28ESdL5igzDlIGSLdtjCKbzqfFWKAA99mnu1WYMj3ofZprEP9yhJ6F5n03KpOYXGRd 9RB68j79aY/kCAHYgMOUSzHniKYM03/nbKN1xwcZ+T/TTnJ7hc/Hh/o5UhWr0z4dfbls JpkA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=eRIdrbJ2jhHVLL9Tut/j9YYL8eIOqR89a+xPlg5BO0U=; b=AfY1ghgpFr5y7jBOKO01D9lhpXt23LE6U+NG/HEPdgnlNHTy2XiJc/nlekoVBhSTTL zun5u5k/0V7D52xQHQ2r14rrjWIvSO6EF0LcgKO9dv+tyd47HjiB5IYN+IWzJxR8uOaR arHGpkYd+QrCzsOZSWpb5KyEoz/7PiiL4orj2wv40JCDi3M3WDKYd8odFAYgaM4DUJgp dl0m98FvaShaTDl67dNpm7jFXlhEntgOMDRxcSmh3kT0/iHsZ/c9VcrlQyMa0w36qjSi WwSywwaM9DnkuOm9FeiqdMellDMTmprnvftpbk70kzrIGG6UOzXosXEMcVZH/MJ23j/r S/bw== X-Gm-Message-State: AOAM531sKc+7mgMG2Rj0qg918thwA1F53UJWjb+nS9BZLsnDcIkpOcHr avaz+rTiVXbI/1OlOTh8sL5vzYrU0Tsd8zJDwag= X-Google-Smtp-Source: ABdhPJyMT0E4fOxaTOJdEe713UBqERQEDC7/usw7J6XiontVMo/EZlk1EZRRx22SXnar09N3hws8MrTfLQISf5YJ/HU= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:3560:8505:40a2:e021]) (user=samitolvanen job=sendgmr) by 2002:a25:3c9:: with SMTP id 192mr14007073ybd.319.1617906533406; Thu, 08 Apr 2021 11:28:53 -0700 (PDT) Date: Thu, 8 Apr 2021 11:28:29 -0700 In-Reply-To: <20210408182843.1754385-1-samitolvanen@google.com> Message-Id: <20210408182843.1754385-5-samitolvanen@google.com> Mime-Version: 1.0 References: <20210408182843.1754385-1-samitolvanen@google.com> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog Subject: [PATCH v6 04/18] module: ensure __cfi_check alignment From: Sami Tolvanen To: Kees Cook Cc: Nathan Chancellor , Nick Desaulniers , Masahiro Yamada , Will Deacon , Jessica Yu , Arnd Bergmann , Tejun Heo , "Paul E. McKenney" , Christoph Hellwig , Peter Zijlstra , Sedat Dilek , Mark Rutland , Catalin Marinas , bpf@vger.kernel.org, linux-hardening@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org CONFIG_CFI_CLANG_SHADOW assumes the __cfi_check() function is page aligned and at the beginning of the .text section. While Clang would normally align the function correctly, it fails to do so for modules with no executable code. This change ensures the correct __cfi_check() location and alignment. It also discards the .eh_frame section, which Clang can generate with certain sanitizers, such as CFI. Link: https://bugs.llvm.org/show_bug.cgi?id=46293 Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Acked-by: Jessica Yu Tested-by: Nathan Chancellor --- scripts/module.lds.S | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) diff --git a/scripts/module.lds.S b/scripts/module.lds.S index 2c52535f9b56..04c5685c25cf 100644 --- a/scripts/module.lds.S +++ b/scripts/module.lds.S @@ -3,10 +3,20 @@ * Archs are free to supply their own linker scripts. ld will * combine them automatically. */ +#ifdef CONFIG_CFI_CLANG +# include +# define ALIGN_CFI ALIGN(PAGE_SIZE) +# define SANITIZER_DISCARDS *(.eh_frame) +#else +# define ALIGN_CFI +# define SANITIZER_DISCARDS +#endif + SECTIONS { /DISCARD/ : { *(.discard) *(.discard.*) + SANITIZER_DISCARDS } __ksymtab 0 : { *(SORT(___ksymtab+*)) } @@ -41,7 +51,14 @@ SECTIONS { *(.rodata..L*) } - .text : { *(.text .text.[0-9a-zA-Z_]*) } + /* + * With CONFIG_CFI_CLANG, we assume __cfi_check is at the beginning + * of the .text section, and is aligned to PAGE_SIZE. + */ + .text : ALIGN_CFI { + *(.text.__cfi_check) + *(.text .text.[0-9a-zA-Z_]* .text..L.cfi*) + } #endif } From patchwork Thu Apr 8 18:28:30 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 12192183 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E9E8FC43460 for ; Thu, 8 Apr 2021 18:29:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CA0D1610A8 for ; Thu, 8 Apr 2021 18:29:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232910AbhDHS3h (ORCPT ); Thu, 8 Apr 2021 14:29:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48668 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232854AbhDHS3S (ORCPT ); Thu, 8 Apr 2021 14:29:18 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 33559C0613E4 for ; Thu, 8 Apr 2021 11:28:56 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id w7so2887404ybq.4 for ; Thu, 08 Apr 2021 11:28:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=LAbK6LGasIRIE7Lniqz15wrZXmrTUww5+Blou7CAxY4=; b=QALHFILqs4GT9aNrYaVc5cwsS2O3moVbeFoKzOyeEX5T8gKLkqRck/QOpiZz8Xgy6u GHtVNUofOR12IrpxyVNLzh3Fm3luiteO+R0LhFXlpqeRo+tjHTcvyNfsF9MHRpthossc Wg97cyUbCitctKczgbE5+WCVvBcaK6Cgpj4Wc+rVPe/2DaGB2rUJAG0m1VBSG7Fh/M1m roMFGI/64bI4JmKbBL1CkGn8Jk3OiOz0zV6tR0qNGANde5gC5dqklluOdFXuiL4Z0XAd tWewvUx6Wqo2mymkJ68/Ko5qbJi4ovkyw6hG9G2+2lVCKJZ+ew7I+xyb8aUSlHCu3d9X 9k9g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=LAbK6LGasIRIE7Lniqz15wrZXmrTUww5+Blou7CAxY4=; b=lMoSYBE8z3mW4zKF9mI4+q+ZmiYOa/ttTzfrRR+GsgLIpTaEUNPwYQi42ZxQx0vnRr WzI2PSDuZhUCWdKmGCzXwxu2TmQOyOD4OI96F+vJlTG544b3Ogm0ROH3tqER+IpIeZD1 rCfuxRX9v9xb6hdfiEC8cY3rKLSNO7/qMtC1b787prjgpvy0fCn5X6L32sk+JjpoQaRh R0wWlKezDit1Yi1vS8lEsQ3ZyTZ/1lkXNBCB90JmeaapT11zs/hzbwU82JnJXI4Hc3SA sWIwwVRGKCqb6GBacvzV6aAJ4oQJNehlgPl0OR0ipq4jBDyVkMekBV8/Pvp4FD604Xg/ iSxw== X-Gm-Message-State: AOAM530ICcK1lsaSSim23HqrHgN4cNi3Bl4FvvZdWl2IOQMOLhWbjMng cUKA7wNeeQOfONfDfyxjxxP20Refsbcn4MmVgrM= X-Google-Smtp-Source: ABdhPJw87AxiqrYpD69IN1mX1v9G5eaNQRMwJPV7w2K9v99iKIA1elCFwP6HzCX6OhW3J4LcJzLgOKik1/QfdcH3TF0= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:3560:8505:40a2:e021]) (user=samitolvanen job=sendgmr) by 2002:a25:f608:: with SMTP id t8mr14077162ybd.496.1617906535437; Thu, 08 Apr 2021 11:28:55 -0700 (PDT) Date: Thu, 8 Apr 2021 11:28:30 -0700 In-Reply-To: <20210408182843.1754385-1-samitolvanen@google.com> Message-Id: <20210408182843.1754385-6-samitolvanen@google.com> Mime-Version: 1.0 References: <20210408182843.1754385-1-samitolvanen@google.com> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog Subject: [PATCH v6 05/18] workqueue: use WARN_ON_FUNCTION_MISMATCH From: Sami Tolvanen To: Kees Cook Cc: Nathan Chancellor , Nick Desaulniers , Masahiro Yamada , Will Deacon , Jessica Yu , Arnd Bergmann , Tejun Heo , "Paul E. McKenney" , Christoph Hellwig , Peter Zijlstra , Sedat Dilek , Mark Rutland , Catalin Marinas , bpf@vger.kernel.org, linux-hardening@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org With CONFIG_CFI_CLANG, a callback function passed to __queue_delayed_work from a module points to a jump table entry defined in the module instead of the one used in the core kernel, which breaks function address equality in this check: WARN_ON_ONCE(timer->function != delayed_work_timer_fn); Use WARN_ON_FUNCTION_MISMATCH() instead to disable the warning when CFI and modules are both enabled. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Tested-by: Nathan Chancellor --- kernel/workqueue.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 79f2319543ce..b19d759e55a5 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -1630,7 +1630,7 @@ static void __queue_delayed_work(int cpu, struct workqueue_struct *wq, struct work_struct *work = &dwork->work; WARN_ON_ONCE(!wq); - WARN_ON_ONCE(timer->function != delayed_work_timer_fn); + WARN_ON_FUNCTION_MISMATCH(timer->function, delayed_work_timer_fn); WARN_ON_ONCE(timer_pending(timer)); WARN_ON_ONCE(!list_empty(&work->entry)); From patchwork Thu Apr 8 18:28:31 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 12192185 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B7CA9C433B4 for ; Thu, 8 Apr 2021 18:29:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9883F61130 for ; Thu, 8 Apr 2021 18:29:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232917AbhDHS3j (ORCPT ); Thu, 8 Apr 2021 14:29:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48620 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232919AbhDHS3V (ORCPT ); Thu, 8 Apr 2021 14:29:21 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 171A3C0613E5 for ; Thu, 8 Apr 2021 11:28:58 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id i6so2883092ybk.2 for ; Thu, 08 Apr 2021 11:28:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=XFW9qholLJYCDGcPvjKxLTh4yh23AN7VnxadLfVAIAk=; b=W7hV9mrblZmrwi9KsES41PXGzLvMgVDFfTIcMVF3q6gtiQ/o3QEJ+5+xML4ri4RlnP YAE11csD2Nkom6m6I0y5v3LjqQhzUd93l2pfiWw5fUTCHSqUHS6TSelFFC3w/jGuFhcQ d6tNqZL51YbPm7Ri6SBgAW0e7qXBVf0IAVO97LLF5rs6UKu0WXrVId0DaDL1XL/gU8Bx WG5Ezaen4l8AI+oNjoTDTAisG2+vW2KB5rDCwzvnU50FwmsR3zNpcOscJZfvcmSuLJUP zIFNnB730D0q3yL2ScU2b9X1VZytTiCgmRAGFn0NDaR0fHtpwA8TZKeVWurwNgQevhXF OxOg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=XFW9qholLJYCDGcPvjKxLTh4yh23AN7VnxadLfVAIAk=; b=k+FR9mGJoXzL6uBVFfM7bnW3GXjr0dsds2lRsK69SyWbgVwnETlHtMzr8PZFfnx59r fVf3H94cdKgc3uZZhk0DoXWmyg1jMrwHmy6ZfLw7D73rLfxeq3rrCexlvyc4LoCRkX2x Bb+JjLlTCDiaVrhq5EMBEOHFpvMt71mqgoC4sUOOCNU17OkgFOaIVOkgITjLraLILICJ 2En8Q5orI/Sn9nfyJpWwvfv3uxZFDJIXBvjjb46mWCFj3LVt6EJv30/oioXc7yI934O4 AKVp0tFNUsHdjKKVseDWo2NZR8vIRqBXViVQAQyvxXKhhvP0bO8MIR+Hlb1EIzW+b2Xg 7WQQ== X-Gm-Message-State: AOAM533R16rMwV6Ux/z/mDKTnvJ12E0QAbEftlM8Xp/p9QG3T6eLjg51 86mx5L87y1KQUeF52VOYp7H9ADpFjvy6iBRnmZw= X-Google-Smtp-Source: ABdhPJy7ksTXDyXgVRFCS8wPoe5BOfA/cFt4wKucNqs3gOI61ZzsQG9rvvWETXTeYmtmmNK12rXYVPUJyObbOk1yBQY= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:3560:8505:40a2:e021]) (user=samitolvanen job=sendgmr) by 2002:a25:c750:: with SMTP id w77mr12752632ybe.340.1617906537243; Thu, 08 Apr 2021 11:28:57 -0700 (PDT) Date: Thu, 8 Apr 2021 11:28:31 -0700 In-Reply-To: <20210408182843.1754385-1-samitolvanen@google.com> Message-Id: <20210408182843.1754385-7-samitolvanen@google.com> Mime-Version: 1.0 References: <20210408182843.1754385-1-samitolvanen@google.com> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog Subject: [PATCH v6 06/18] kthread: use WARN_ON_FUNCTION_MISMATCH From: Sami Tolvanen To: Kees Cook Cc: Nathan Chancellor , Nick Desaulniers , Masahiro Yamada , Will Deacon , Jessica Yu , Arnd Bergmann , Tejun Heo , "Paul E. McKenney" , Christoph Hellwig , Peter Zijlstra , Sedat Dilek , Mark Rutland , Catalin Marinas , bpf@vger.kernel.org, linux-hardening@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org With CONFIG_CFI_CLANG, a callback function passed to __kthread_queue_delayed_work from a module points to a jump table entry defined in the module instead of the one used in the core kernel, which breaks function address equality in this check: WARN_ON_ONCE(timer->function != ktead_delayed_work_timer_fn); Use WARN_ON_FUNCTION_MISMATCH() instead to disable the warning when CFI and modules are both enabled. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Tested-by: Nathan Chancellor --- kernel/kthread.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/kthread.c b/kernel/kthread.c index 1578973c5740..a1972eba2917 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -963,7 +963,8 @@ static void __kthread_queue_delayed_work(struct kthread_worker *worker, struct timer_list *timer = &dwork->timer; struct kthread_work *work = &dwork->work; - WARN_ON_ONCE(timer->function != kthread_delayed_work_timer_fn); + WARN_ON_FUNCTION_MISMATCH(timer->function, + kthread_delayed_work_timer_fn); /* * If @delay is 0, queue @dwork->work immediately. This is for From patchwork Thu Apr 8 18:28:32 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 12192187 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.2 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DCDC9C433B4 for ; Thu, 8 Apr 2021 18:29:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BA915610A8 for ; Thu, 8 Apr 2021 18:29:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232967AbhDHS3k (ORCPT ); Thu, 8 Apr 2021 14:29:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48694 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232933AbhDHS3X (ORCPT ); Thu, 8 Apr 2021 14:29:23 -0400 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 70DD9C0613D9 for ; Thu, 8 Apr 2021 11:28:59 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id w7so2887530ybq.4 for ; Thu, 08 Apr 2021 11:28:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=qNLGON3mLEW9otlCYITUwcgh/bW+ooEbGJnw36Nqnno=; b=jj7kg+VOYnwmWzkTWEHiW28jPkIwiSNlmYCpDvaVmnqrHmBOyAOIMYPWJ9h864B4wy Tzp0pjqCpebrLADZgh91W+KKB8eGueD1VwBS6L7cebE7ZSkkUJu44191T9NS6Rskdh0h 8KxnMbVMi9us5lmvFv05UFsGi1dICU0/jOW35jW1yFDSqWjFoKWggx118j+DDE3/RxML zsfSf8gO1o/pVNO2RMm+vd+3gL61iabM9gmKVtTjnQFryvd6INtxjocfZiBVqnr7RGy/ cE5ecHhNG8V4CRTzylPDxAIUG1JiZs88nEOCENsfA99dniQCG6exDwniRiS5DuiKcDZa k0/Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=qNLGON3mLEW9otlCYITUwcgh/bW+ooEbGJnw36Nqnno=; b=kDGyhbub9xFM0R22Y/ezc/3pgV4QUpTb8IpKBmZZGsbUMxJgO5BKVePSd1HnML7Smz fJIVCjt5sw4uo3Lytd2avZcu5JEQQ7lCgwJSBYGlEdn42+1dO0LUi5HtxW1NgnIYZi1D vYdVkduHlDIZ6ABmQcs4UxJLRdtovcfMt3hooco1Cb9tdEkkhPlW+0FjpIV+tHENAurg jV2J30QV/y46EF9KgYbQMOTr/v4w/kopCYVTb0GM8n+RxsV6xMjnIOyjJk64g0yCXhO9 dG+O9zYAQ4pBkBu95Bb0qriQVP7IFLDKbNhCMrsHfh1ah7p3/EvW/UVxbBmt4D1YjoCn JlPw== X-Gm-Message-State: AOAM530MhyDjnww2w9puQx5T+Tujyo3sdhRZu/EiZBVDebCm9vGWG6du RhHVgyWgZW2xv+uoqOSJsqluVEsuILg6b6QDMSY= X-Google-Smtp-Source: ABdhPJxUVsuqAxqz+Uc34PB7dmpMvtjLBCQlu4buaoD1UTMPY6dYbIzL2DM8WBBiz1+HV0EZ0aw7CIFzq9DHWz0IVJg= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:3560:8505:40a2:e021]) (user=samitolvanen job=sendgmr) by 2002:a25:360a:: with SMTP id d10mr13411630yba.473.1617906539163; Thu, 08 Apr 2021 11:28:59 -0700 (PDT) Date: Thu, 8 Apr 2021 11:28:32 -0700 In-Reply-To: <20210408182843.1754385-1-samitolvanen@google.com> Message-Id: <20210408182843.1754385-8-samitolvanen@google.com> Mime-Version: 1.0 References: <20210408182843.1754385-1-samitolvanen@google.com> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog Subject: [PATCH v6 07/18] kallsyms: strip ThinLTO hashes from static functions From: Sami Tolvanen To: Kees Cook Cc: Nathan Chancellor , Nick Desaulniers , Masahiro Yamada , Will Deacon , Jessica Yu , Arnd Bergmann , Tejun Heo , "Paul E. McKenney" , Christoph Hellwig , Peter Zijlstra , Sedat Dilek , Mark Rutland , Catalin Marinas , bpf@vger.kernel.org, linux-hardening@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org With CONFIG_CFI_CLANG and ThinLTO, Clang appends a hash to the names of all static functions not marked __used. This can break userspace tools that don't expect the function name to change, so strip out the hash from the output. Suggested-by: Jack Pham Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Tested-by: Nathan Chancellor --- kernel/kallsyms.c | 55 ++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 50 insertions(+), 5 deletions(-) diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c index 8043a90aa50e..c851ca0ed357 100644 --- a/kernel/kallsyms.c +++ b/kernel/kallsyms.c @@ -161,6 +161,27 @@ static unsigned long kallsyms_sym_address(int idx) return kallsyms_relative_base - 1 - kallsyms_offsets[idx]; } +#if defined(CONFIG_CFI_CLANG) && defined(CONFIG_LTO_CLANG_THIN) +/* + * LLVM appends a hash to static function names when ThinLTO and CFI are + * both enabled, i.e. foo() becomes foo$707af9a22804d33c81801f27dcfe489b. + * This causes confusion and potentially breaks user space tools, so we + * strip the suffix from expanded symbol names. + */ +static inline bool cleanup_symbol_name(char *s) +{ + char *res; + + res = strrchr(s, '$'); + if (res) + *res = '\0'; + + return res != NULL; +} +#else +static inline bool cleanup_symbol_name(char *s) { return false; } +#endif + /* Lookup the address for this symbol. Returns 0 if not found. */ unsigned long kallsyms_lookup_name(const char *name) { @@ -173,6 +194,9 @@ unsigned long kallsyms_lookup_name(const char *name) if (strcmp(namebuf, name) == 0) return kallsyms_sym_address(i); + + if (cleanup_symbol_name(namebuf) && strcmp(namebuf, name) == 0) + return kallsyms_sym_address(i); } return module_kallsyms_lookup_name(name); } @@ -303,7 +327,9 @@ const char *kallsyms_lookup(unsigned long addr, namebuf, KSYM_NAME_LEN); if (modname) *modname = NULL; - return namebuf; + + ret = namebuf; + goto found; } /* See if it's in a module or a BPF JITed image. */ @@ -316,11 +342,16 @@ const char *kallsyms_lookup(unsigned long addr, if (!ret) ret = ftrace_mod_address_lookup(addr, symbolsize, offset, modname, namebuf); + +found: + cleanup_symbol_name(namebuf); return ret; } int lookup_symbol_name(unsigned long addr, char *symname) { + int res; + symname[0] = '\0'; symname[KSYM_NAME_LEN - 1] = '\0'; @@ -331,15 +362,23 @@ int lookup_symbol_name(unsigned long addr, char *symname) /* Grab name */ kallsyms_expand_symbol(get_symbol_offset(pos), symname, KSYM_NAME_LEN); - return 0; + goto found; } /* See if it's in a module. */ - return lookup_module_symbol_name(addr, symname); + res = lookup_module_symbol_name(addr, symname); + if (res) + return res; + +found: + cleanup_symbol_name(symname); + return 0; } int lookup_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name) { + int res; + name[0] = '\0'; name[KSYM_NAME_LEN - 1] = '\0'; @@ -351,10 +390,16 @@ int lookup_symbol_attrs(unsigned long addr, unsigned long *size, kallsyms_expand_symbol(get_symbol_offset(pos), name, KSYM_NAME_LEN); modname[0] = '\0'; - return 0; + goto found; } /* See if it's in a module. */ - return lookup_module_symbol_attrs(addr, size, offset, modname, name); + res = lookup_module_symbol_attrs(addr, size, offset, modname, name); + if (res) + return res; + +found: + cleanup_symbol_name(name); + return 0; } /* Look up a kernel symbol and return it in a text buffer. */ From patchwork Thu Apr 8 18:28:33 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 12192189 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 768DCC433B4 for ; Thu, 8 Apr 2021 18:29:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 59CFE610FC for ; Thu, 8 Apr 2021 18:29:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232891AbhDHS3y (ORCPT ); Thu, 8 Apr 2021 14:29:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48706 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232956AbhDHS3a (ORCPT ); Thu, 8 Apr 2021 14:29:30 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C1F2FC061794 for ; Thu, 8 Apr 2021 11:29:01 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id 131so2862051ybp.16 for ; Thu, 08 Apr 2021 11:29:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=T2ovzaB0NMgTSr/OQHoRsOuIMdugM8hNdn5wpYAlfF8=; b=b/XnAFSzIGeFZL5t4c3a08ji5ExjHKdf/SwND+STd8nJjKG2hFi8IK6+LIkx2BL1C9 wA58dA9Twv0RudfR+z0WKHeJHzBjE5MCPeNpBMSpRhTqgwMv1lMdb5OMvQvJs03AJdqF cvNhS4rRrIm5NEuMJcbOn0Qic4skZtQ7ODdDOjE+31zXh7wKiynNzNVauckEuvoTxUxC kDIa3FfiN8wZ72m0SiVMTOm77/X5XsJn517NuQnl/oz5AyexntdTHwnjiUme+uS7gPSa RYYiKdwwNKXeM2PUjRJWR//28taSyDm0VOQQzPOC2K3Pq3M24yOOt7lwowsUBlWOxQbw tw4w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=T2ovzaB0NMgTSr/OQHoRsOuIMdugM8hNdn5wpYAlfF8=; b=gOIJyqSt0KPLPGtOP6hwRLP1aH15S5l4q+YzXv499isqFGy8itVFVARozbUoZ0zeo4 K22WfkCnNymIpiyKE7sLdTHbFUB+lFsacxkoRulwQtBOdsDK3QOBH8lz9aDx4wODSEZj uYxIv48Bqz+eqSCKQZQbP0mSXBFZ0ydH2LG8U+5vtAi8rzQJN4Aw8bZxGamdTPi0iMpL s5JiH7y+ZmeBGr3FG/r+4AbRRDzsTX9EcWRrejxmJ0YpFUdeyMkh4v6yrI3s6lntm90h 1JkoKlzMHad82HV9ttriwYK+k270CXK7ie2acFqahXADeikVXcheC8QH++ZZUrAbhQhO /u2Q== X-Gm-Message-State: AOAM530qul0ms1sHuemnt8rKB/3arMhsbgAHYyvb5lqY73ohdcLY1zVB 7m6gUOpPWhQWyd13mOXWN3u62fel8z0pjsS/430= X-Google-Smtp-Source: ABdhPJy28p/s1E3yXdiEmOPhfW5oMkIPebIbR+7sk7/VA4kOnWJlonwcxFpLfp3KgtW+U+9qgib7kFL/mIu5lYyr5IA= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:3560:8505:40a2:e021]) (user=samitolvanen job=sendgmr) by 2002:a25:fc05:: with SMTP id v5mr2410558ybd.192.1617906540963; Thu, 08 Apr 2021 11:29:00 -0700 (PDT) Date: Thu, 8 Apr 2021 11:28:33 -0700 In-Reply-To: <20210408182843.1754385-1-samitolvanen@google.com> Message-Id: <20210408182843.1754385-9-samitolvanen@google.com> Mime-Version: 1.0 References: <20210408182843.1754385-1-samitolvanen@google.com> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog Subject: [PATCH v6 08/18] bpf: disable CFI in dispatcher functions From: Sami Tolvanen To: Kees Cook Cc: Nathan Chancellor , Nick Desaulniers , Masahiro Yamada , Will Deacon , Jessica Yu , Arnd Bergmann , Tejun Heo , "Paul E. McKenney" , Christoph Hellwig , Peter Zijlstra , Sedat Dilek , Mark Rutland , Catalin Marinas , bpf@vger.kernel.org, linux-hardening@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org BPF dispatcher functions are patched at runtime to perform direct instead of indirect calls. Disable CFI for the dispatcher functions to avoid conflicts. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Tested-by: Nathan Chancellor --- include/linux/bpf.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 3625f019767d..2f46f98479e1 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -650,7 +650,7 @@ struct bpf_dispatcher { struct bpf_ksym ksym; }; -static __always_inline unsigned int bpf_dispatcher_nop_func( +static __always_inline __nocfi unsigned int bpf_dispatcher_nop_func( const void *ctx, const struct bpf_insn *insnsi, unsigned int (*bpf_func)(const void *, @@ -678,7 +678,7 @@ void bpf_trampoline_put(struct bpf_trampoline *tr); } #define DEFINE_BPF_DISPATCHER(name) \ - noinline unsigned int bpf_dispatcher_##name##_func( \ + noinline __nocfi unsigned int bpf_dispatcher_##name##_func( \ const void *ctx, \ const struct bpf_insn *insnsi, \ unsigned int (*bpf_func)(const void *, \ From patchwork Thu Apr 8 18:28:34 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 12192191 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E4DFBC43461 for ; Thu, 8 Apr 2021 18:29:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C09B361108 for ; Thu, 8 Apr 2021 18:29:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232829AbhDHS3w (ORCPT ); Thu, 8 Apr 2021 14:29:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48708 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232889AbhDHS33 (ORCPT ); Thu, 8 Apr 2021 14:29:29 -0400 Received: from mail-qt1-x849.google.com (mail-qt1-x849.google.com [IPv6:2607:f8b0:4864:20::849]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8895AC061797 for ; Thu, 8 Apr 2021 11:29:03 -0700 (PDT) Received: by mail-qt1-x849.google.com with SMTP id n21so1107229qtv.4 for ; Thu, 08 Apr 2021 11:29:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=xEgJ+NAjM5FxzF9bQSDPWb3XbRSfsF189Czr5tFjjno=; b=F2Jw4Yroc8uk3/MChQzH5zrtUXeRKgVAg/ebDio2XbAtgEH03eiY8KpXzbbpQt+2Gp oi9c6HyQLQs+6pVESamj6I7SWooGCDdLPi6T96rwniDsF4wWahL4MiXqRGEXNcxb5rSt zcGQx/QZ7lMB2LmR10wI4lqQ8C4DVgXr45oEnMeGRQoMO48xXCud+evJcCtqtD1Ity5L PdshAivHLebCaHU7hkjahva1Pnz7q5nA15S+0jKz45ZKDztVOzLJ2f8IsDlDMfjy/VVe VtcYQ+x+N8OmjV3ArsG1wL62EmZRYlcPzH3g0QnISi+gCQTGODQpXVC52SsnY3J3l/u7 yRfg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=xEgJ+NAjM5FxzF9bQSDPWb3XbRSfsF189Czr5tFjjno=; b=bN54FhTK/e77vsHYnQkIhYQJA12K0RhOi1bSHtbnLwIVj4PeL6nZ5f6sX7wOqXvV2W FZWvHh80RKhoD1V0s+/pEuQu7VOhaF3ehn6z7EJlfRt/F3Eb8Z9gwPQvASn7Zfurht+n WYrN0yNn9F8wVm2IX2T8J68kZdb/4XefMjhwMFdvrTVpJuGQZ2JeKaeSNyqwLefYnlq+ QAzXnL5u/FJ4uk6rrGspoW81vlebEiqpFaiS8i7cPBk0n4lwqmFEXM+BBxplL2NwKm1J 9MabuguO+OMQ7fcsDZwgZSDLI8vP2WLA0WYUK1FzwOMONQkTYv0wN8Dje5XSrvxNb4Nv IWvw== X-Gm-Message-State: AOAM530Z1g4PIj19Q2AES+JHFusV+GNWrhd4u5diGoyT0NV9/eSjF0zq 6Gt32fkumuy3N6mSTyjgacgNT0BJr1g56JlnbJs= X-Google-Smtp-Source: ABdhPJwMexZh/Jt/Xa08r0bRBsjvPk4r1/qMD9HBY+rABifHsdrJc2NNkVAeOuPl+WlMl4dRjb5TPy5A/CQx7LqxA0I= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:3560:8505:40a2:e021]) (user=samitolvanen job=sendgmr) by 2002:a05:6214:1870:: with SMTP id eh16mr10009149qvb.23.1617906542706; Thu, 08 Apr 2021 11:29:02 -0700 (PDT) Date: Thu, 8 Apr 2021 11:28:34 -0700 In-Reply-To: <20210408182843.1754385-1-samitolvanen@google.com> Message-Id: <20210408182843.1754385-10-samitolvanen@google.com> Mime-Version: 1.0 References: <20210408182843.1754385-1-samitolvanen@google.com> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog Subject: [PATCH v6 09/18] treewide: Change list_sort to use const pointers From: Sami Tolvanen To: Kees Cook Cc: Nathan Chancellor , Nick Desaulniers , Masahiro Yamada , Will Deacon , Jessica Yu , Arnd Bergmann , Tejun Heo , "Paul E. McKenney" , Christoph Hellwig , Peter Zijlstra , Sedat Dilek , Mark Rutland , Catalin Marinas , bpf@vger.kernel.org, linux-hardening@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org list_sort() internally casts the comparison function passed to it to a different type with constant struct list_head pointers, and uses this pointer to call the functions, which trips indirect call Control-Flow Integrity (CFI) checking. Instead of removing the consts, this change defines the list_cmp_func_t type and changes the comparison function types of all list_sort() callers to use const pointers, thus avoiding type mismatches. Suggested-by: Nick Desaulniers Signed-off-by: Sami Tolvanen Reviewed-by: Nick Desaulniers Reviewed-by: Christoph Hellwig Reviewed-by: Kees Cook Tested-by: Nick Desaulniers Tested-by: Nathan Chancellor --- arch/arm64/kvm/vgic/vgic-its.c | 8 ++++---- arch/arm64/kvm/vgic/vgic.c | 3 ++- block/blk-mq-sched.c | 3 ++- block/blk-mq.c | 3 ++- drivers/acpi/nfit/core.c | 3 ++- drivers/acpi/numa/hmat.c | 3 ++- drivers/clk/keystone/sci-clk.c | 4 ++-- drivers/gpu/drm/drm_modes.c | 3 ++- drivers/gpu/drm/i915/gt/intel_engine_user.c | 3 ++- drivers/gpu/drm/i915/gvt/debugfs.c | 2 +- drivers/gpu/drm/i915/selftests/i915_gem_gtt.c | 3 ++- drivers/gpu/drm/radeon/radeon_cs.c | 4 ++-- .../hw/usnic/usnic_uiom_interval_tree.c | 3 ++- drivers/interconnect/qcom/bcm-voter.c | 2 +- drivers/md/raid5.c | 3 ++- drivers/misc/sram.c | 4 ++-- drivers/nvme/host/core.c | 3 ++- .../pci/controller/cadence/pcie-cadence-host.c | 3 ++- drivers/spi/spi-loopback-test.c | 3 ++- fs/btrfs/raid56.c | 3 ++- fs/btrfs/tree-log.c | 3 ++- fs/btrfs/volumes.c | 3 ++- fs/ext4/fsmap.c | 4 ++-- fs/gfs2/glock.c | 3 ++- fs/gfs2/log.c | 2 +- fs/gfs2/lops.c | 3 ++- fs/iomap/buffered-io.c | 3 ++- fs/ubifs/gc.c | 7 ++++--- fs/ubifs/replay.c | 4 ++-- fs/xfs/scrub/bitmap.c | 4 ++-- fs/xfs/xfs_bmap_item.c | 4 ++-- fs/xfs/xfs_buf.c | 6 +++--- fs/xfs/xfs_extent_busy.c | 4 ++-- fs/xfs/xfs_extent_busy.h | 3 ++- fs/xfs/xfs_extfree_item.c | 4 ++-- fs/xfs/xfs_refcount_item.c | 4 ++-- fs/xfs/xfs_rmap_item.c | 4 ++-- include/linux/list_sort.h | 7 ++++--- lib/list_sort.c | 17 ++++++----------- lib/test_list_sort.c | 3 ++- net/tipc/name_table.c | 4 ++-- 41 files changed, 90 insertions(+), 72 deletions(-) diff --git a/arch/arm64/kvm/vgic/vgic-its.c b/arch/arm64/kvm/vgic/vgic-its.c index 40cbaca81333..b9518f94bd43 100644 --- a/arch/arm64/kvm/vgic/vgic-its.c +++ b/arch/arm64/kvm/vgic/vgic-its.c @@ -2190,8 +2190,8 @@ static int vgic_its_restore_ite(struct vgic_its *its, u32 event_id, return offset; } -static int vgic_its_ite_cmp(void *priv, struct list_head *a, - struct list_head *b) +static int vgic_its_ite_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct its_ite *itea = container_of(a, struct its_ite, ite_list); struct its_ite *iteb = container_of(b, struct its_ite, ite_list); @@ -2329,8 +2329,8 @@ static int vgic_its_restore_dte(struct vgic_its *its, u32 id, return offset; } -static int vgic_its_device_cmp(void *priv, struct list_head *a, - struct list_head *b) +static int vgic_its_device_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct its_device *deva = container_of(a, struct its_device, dev_list); struct its_device *devb = container_of(b, struct its_device, dev_list); diff --git a/arch/arm64/kvm/vgic/vgic.c b/arch/arm64/kvm/vgic/vgic.c index 1c597c9885fa..15b666200f0b 100644 --- a/arch/arm64/kvm/vgic/vgic.c +++ b/arch/arm64/kvm/vgic/vgic.c @@ -255,7 +255,8 @@ static struct kvm_vcpu *vgic_target_oracle(struct vgic_irq *irq) * Return negative if "a" sorts before "b", 0 to preserve order, and positive * to sort "b" before "a". */ -static int vgic_irq_cmp(void *priv, struct list_head *a, struct list_head *b) +static int vgic_irq_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct vgic_irq *irqa = container_of(a, struct vgic_irq, ap_list); struct vgic_irq *irqb = container_of(b, struct vgic_irq, ap_list); diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c index e1e997af89a0..3ebd6f10f728 100644 --- a/block/blk-mq-sched.c +++ b/block/blk-mq-sched.c @@ -75,7 +75,8 @@ void blk_mq_sched_restart(struct blk_mq_hw_ctx *hctx) blk_mq_run_hw_queue(hctx, true); } -static int sched_rq_cmp(void *priv, struct list_head *a, struct list_head *b) +static int sched_rq_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct request *rqa = container_of(a, struct request, queuelist); struct request *rqb = container_of(b, struct request, queuelist); diff --git a/block/blk-mq.c b/block/blk-mq.c index d4d7c1caa439..4e3a70ab5be1 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1895,7 +1895,8 @@ void blk_mq_insert_requests(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx, spin_unlock(&ctx->lock); } -static int plug_rq_cmp(void *priv, struct list_head *a, struct list_head *b) +static int plug_rq_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct request *rqa = container_of(a, struct request, queuelist); struct request *rqb = container_of(b, struct request, queuelist); diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c index 8c5dde628405..d15e3ee93b5b 100644 --- a/drivers/acpi/nfit/core.c +++ b/drivers/acpi/nfit/core.c @@ -1195,7 +1195,8 @@ static int __nfit_mem_init(struct acpi_nfit_desc *acpi_desc, return 0; } -static int nfit_mem_cmp(void *priv, struct list_head *_a, struct list_head *_b) +static int nfit_mem_cmp(void *priv, const struct list_head *_a, + const struct list_head *_b) { struct nfit_mem *a = container_of(_a, typeof(*a), list); struct nfit_mem *b = container_of(_b, typeof(*b), list); diff --git a/drivers/acpi/numa/hmat.c b/drivers/acpi/numa/hmat.c index cb73a5d6ea76..137a5dd880c2 100644 --- a/drivers/acpi/numa/hmat.c +++ b/drivers/acpi/numa/hmat.c @@ -558,7 +558,8 @@ static bool hmat_update_best(u8 type, u32 value, u32 *best) return updated; } -static int initiator_cmp(void *priv, struct list_head *a, struct list_head *b) +static int initiator_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct memory_initiator *ia; struct memory_initiator *ib; diff --git a/drivers/clk/keystone/sci-clk.c b/drivers/clk/keystone/sci-clk.c index aaf31abe1c8f..7e1b136e71ae 100644 --- a/drivers/clk/keystone/sci-clk.c +++ b/drivers/clk/keystone/sci-clk.c @@ -503,8 +503,8 @@ static int ti_sci_scan_clocks_from_fw(struct sci_clk_provider *provider) #else -static int _cmp_sci_clk_list(void *priv, struct list_head *a, - struct list_head *b) +static int _cmp_sci_clk_list(void *priv, const struct list_head *a, + const struct list_head *b) { struct sci_clk *ca = container_of(a, struct sci_clk, node); struct sci_clk *cb = container_of(b, struct sci_clk, node); diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c index 1ac67d4505e0..6662d0457ad6 100644 --- a/drivers/gpu/drm/drm_modes.c +++ b/drivers/gpu/drm/drm_modes.c @@ -1290,7 +1290,8 @@ EXPORT_SYMBOL(drm_mode_prune_invalid); * Negative if @lh_a is better than @lh_b, zero if they're equivalent, or * positive if @lh_b is better than @lh_a. */ -static int drm_mode_compare(void *priv, struct list_head *lh_a, struct list_head *lh_b) +static int drm_mode_compare(void *priv, const struct list_head *lh_a, + const struct list_head *lh_b) { struct drm_display_mode *a = list_entry(lh_a, struct drm_display_mode, head); struct drm_display_mode *b = list_entry(lh_b, struct drm_display_mode, head); diff --git a/drivers/gpu/drm/i915/gt/intel_engine_user.c b/drivers/gpu/drm/i915/gt/intel_engine_user.c index 34e6096f196e..da21d2a10cc9 100644 --- a/drivers/gpu/drm/i915/gt/intel_engine_user.c +++ b/drivers/gpu/drm/i915/gt/intel_engine_user.c @@ -49,7 +49,8 @@ static const u8 uabi_classes[] = { [VIDEO_ENHANCEMENT_CLASS] = I915_ENGINE_CLASS_VIDEO_ENHANCE, }; -static int engine_cmp(void *priv, struct list_head *A, struct list_head *B) +static int engine_cmp(void *priv, const struct list_head *A, + const struct list_head *B) { const struct intel_engine_cs *a = container_of((struct rb_node *)A, typeof(*a), uabi_node); diff --git a/drivers/gpu/drm/i915/gvt/debugfs.c b/drivers/gpu/drm/i915/gvt/debugfs.c index 62e6a14ad58e..9f1c209d9251 100644 --- a/drivers/gpu/drm/i915/gvt/debugfs.c +++ b/drivers/gpu/drm/i915/gvt/debugfs.c @@ -41,7 +41,7 @@ struct diff_mmio { /* Compare two diff_mmio items. */ static int mmio_offset_compare(void *priv, - struct list_head *a, struct list_head *b) + const struct list_head *a, const struct list_head *b) { struct diff_mmio *ma; struct diff_mmio *mb; diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c b/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c index c1adea8765a9..52b9c39e0155 100644 --- a/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c +++ b/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c @@ -1076,7 +1076,8 @@ static int igt_ppgtt_shrink_boom(void *arg) return exercise_ppgtt(arg, shrink_boom); } -static int sort_holes(void *priv, struct list_head *A, struct list_head *B) +static int sort_holes(void *priv, const struct list_head *A, + const struct list_head *B) { struct drm_mm_node *a = list_entry(A, typeof(*a), hole_stack); struct drm_mm_node *b = list_entry(B, typeof(*b), hole_stack); diff --git a/drivers/gpu/drm/radeon/radeon_cs.c b/drivers/gpu/drm/radeon/radeon_cs.c index 35e937d39b51..1a5c3db1d53b 100644 --- a/drivers/gpu/drm/radeon/radeon_cs.c +++ b/drivers/gpu/drm/radeon/radeon_cs.c @@ -393,8 +393,8 @@ int radeon_cs_parser_init(struct radeon_cs_parser *p, void *data) return 0; } -static int cmp_size_smaller_first(void *priv, struct list_head *a, - struct list_head *b) +static int cmp_size_smaller_first(void *priv, const struct list_head *a, + const struct list_head *b) { struct radeon_bo_list *la = list_entry(a, struct radeon_bo_list, tv.head); struct radeon_bo_list *lb = list_entry(b, struct radeon_bo_list, tv.head); diff --git a/drivers/infiniband/hw/usnic/usnic_uiom_interval_tree.c b/drivers/infiniband/hw/usnic/usnic_uiom_interval_tree.c index d399523206c7..29d71267af78 100644 --- a/drivers/infiniband/hw/usnic/usnic_uiom_interval_tree.c +++ b/drivers/infiniband/hw/usnic/usnic_uiom_interval_tree.c @@ -83,7 +83,8 @@ usnic_uiom_interval_node_alloc(long int start, long int last, int ref_cnt, return interval; } -static int interval_cmp(void *priv, struct list_head *a, struct list_head *b) +static int interval_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct usnic_uiom_interval_node *node_a, *node_b; diff --git a/drivers/interconnect/qcom/bcm-voter.c b/drivers/interconnect/qcom/bcm-voter.c index 1cc565bce2f4..d1591a28b743 100644 --- a/drivers/interconnect/qcom/bcm-voter.c +++ b/drivers/interconnect/qcom/bcm-voter.c @@ -39,7 +39,7 @@ struct bcm_voter { u32 tcs_wait; }; -static int cmp_vcd(void *priv, struct list_head *a, struct list_head *b) +static int cmp_vcd(void *priv, const struct list_head *a, const struct list_head *b) { const struct qcom_icc_bcm *bcm_a = list_entry(a, struct qcom_icc_bcm, list); const struct qcom_icc_bcm *bcm_b = list_entry(b, struct qcom_icc_bcm, list); diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 5d57a5bd171f..841e1c1aa5e6 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -953,7 +953,8 @@ static void dispatch_bio_list(struct bio_list *tmp) submit_bio_noacct(bio); } -static int cmp_stripe(void *priv, struct list_head *a, struct list_head *b) +static int cmp_stripe(void *priv, const struct list_head *a, + const struct list_head *b) { const struct r5pending_data *da = list_entry(a, struct r5pending_data, sibling); diff --git a/drivers/misc/sram.c b/drivers/misc/sram.c index 6c1a23cb3e8c..202bf951e909 100644 --- a/drivers/misc/sram.c +++ b/drivers/misc/sram.c @@ -144,8 +144,8 @@ static void sram_free_partitions(struct sram_dev *sram) } } -static int sram_reserve_cmp(void *priv, struct list_head *a, - struct list_head *b) +static int sram_reserve_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct sram_reserve *ra = list_entry(a, struct sram_reserve, list); struct sram_reserve *rb = list_entry(b, struct sram_reserve, list); diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 0896e21642be..5eaaa51a5e30 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -3855,7 +3855,8 @@ static int nvme_init_ns_head(struct nvme_ns *ns, unsigned nsid, return ret; } -static int ns_cmp(void *priv, struct list_head *a, struct list_head *b) +static int ns_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct nvme_ns *nsa = container_of(a, struct nvme_ns, list); struct nvme_ns *nsb = container_of(b, struct nvme_ns, list); diff --git a/drivers/pci/controller/cadence/pcie-cadence-host.c b/drivers/pci/controller/cadence/pcie-cadence-host.c index 73dcf8cf98fb..ae1c55503513 100644 --- a/drivers/pci/controller/cadence/pcie-cadence-host.c +++ b/drivers/pci/controller/cadence/pcie-cadence-host.c @@ -345,7 +345,8 @@ static int cdns_pcie_host_bar_config(struct cdns_pcie_rc *rc, return 0; } -static int cdns_pcie_host_dma_ranges_cmp(void *priv, struct list_head *a, struct list_head *b) +static int cdns_pcie_host_dma_ranges_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct resource_entry *entry1, *entry2; diff --git a/drivers/spi/spi-loopback-test.c b/drivers/spi/spi-loopback-test.c index df981e55c24c..f1cf2232f0b5 100644 --- a/drivers/spi/spi-loopback-test.c +++ b/drivers/spi/spi-loopback-test.c @@ -454,7 +454,8 @@ struct rx_ranges { u8 *end; }; -static int rx_ranges_cmp(void *priv, struct list_head *a, struct list_head *b) +static int rx_ranges_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct rx_ranges *rx_a = list_entry(a, struct rx_ranges, list); struct rx_ranges *rx_b = list_entry(b, struct rx_ranges, list); diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c index 8c31357f08ed..f4139de63b2e 100644 --- a/fs/btrfs/raid56.c +++ b/fs/btrfs/raid56.c @@ -1634,7 +1634,8 @@ struct btrfs_plug_cb { /* * rbios on the plug list are sorted for easier merging. */ -static int plug_cmp(void *priv, struct list_head *a, struct list_head *b) +static int plug_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct btrfs_raid_bio *ra = container_of(a, struct btrfs_raid_bio, plug_list); diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 92a368627791..00a88bd8105e 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -4136,7 +4136,8 @@ static noinline int copy_items(struct btrfs_trans_handle *trans, return ret; } -static int extent_cmp(void *priv, struct list_head *a, struct list_head *b) +static int extent_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct extent_map *em1, *em2; diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 1c6810bbaf8b..912dd8b9f156 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -1224,7 +1224,8 @@ static int open_fs_devices(struct btrfs_fs_devices *fs_devices, return 0; } -static int devid_cmp(void *priv, struct list_head *a, struct list_head *b) +static int devid_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct btrfs_device *dev1, *dev2; diff --git a/fs/ext4/fsmap.c b/fs/ext4/fsmap.c index 4c2a9fe30067..4493ef0c715e 100644 --- a/fs/ext4/fsmap.c +++ b/fs/ext4/fsmap.c @@ -354,8 +354,8 @@ static unsigned int ext4_getfsmap_find_sb(struct super_block *sb, /* Compare two fsmap items. */ static int ext4_getfsmap_compare(void *priv, - struct list_head *a, - struct list_head *b) + const struct list_head *a, + const struct list_head *b) { struct ext4_fsmap *fa; struct ext4_fsmap *fb; diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c index 9567520d79f7..c06a6cdf05de 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -1732,7 +1732,8 @@ void gfs2_glock_complete(struct gfs2_glock *gl, int ret) spin_unlock(&gl->gl_lockref.lock); } -static int glock_cmp(void *priv, struct list_head *a, struct list_head *b) +static int glock_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct gfs2_glock *gla, *glb; diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c index 6410281546f9..88649b43fcff 100644 --- a/fs/gfs2/log.c +++ b/fs/gfs2/log.c @@ -695,7 +695,7 @@ void log_flush_wait(struct gfs2_sbd *sdp) } } -static int ip_cmp(void *priv, struct list_head *a, struct list_head *b) +static int ip_cmp(void *priv, const struct list_head *a, const struct list_head *b) { struct gfs2_inode *ipa, *ipb; diff --git a/fs/gfs2/lops.c b/fs/gfs2/lops.c index a82f4747aa8d..b4809967efc6 100644 --- a/fs/gfs2/lops.c +++ b/fs/gfs2/lops.c @@ -634,7 +634,8 @@ static void gfs2_check_magic(struct buffer_head *bh) kunmap_atomic(kaddr); } -static int blocknr_cmp(void *priv, struct list_head *a, struct list_head *b) +static int blocknr_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct gfs2_bufdata *bda, *bdb; diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index 414769a6ad11..0129e6bab985 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -1155,7 +1155,8 @@ iomap_ioend_try_merge(struct iomap_ioend *ioend, struct list_head *more_ioends, EXPORT_SYMBOL_GPL(iomap_ioend_try_merge); static int -iomap_ioend_compare(void *priv, struct list_head *a, struct list_head *b) +iomap_ioend_compare(void *priv, const struct list_head *a, + const struct list_head *b) { struct iomap_ioend *ia = container_of(a, struct iomap_ioend, io_list); struct iomap_ioend *ib = container_of(b, struct iomap_ioend, io_list); diff --git a/fs/ubifs/gc.c b/fs/ubifs/gc.c index a4aaeea63893..dc3e26e9ed7b 100644 --- a/fs/ubifs/gc.c +++ b/fs/ubifs/gc.c @@ -102,7 +102,8 @@ static int switch_gc_head(struct ubifs_info *c) * This function compares data nodes @a and @b. Returns %1 if @a has greater * inode or block number, and %-1 otherwise. */ -static int data_nodes_cmp(void *priv, struct list_head *a, struct list_head *b) +static int data_nodes_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { ino_t inuma, inumb; struct ubifs_info *c = priv; @@ -145,8 +146,8 @@ static int data_nodes_cmp(void *priv, struct list_head *a, struct list_head *b) * first and sorted by length in descending order. Directory entry nodes go * after inode nodes and are sorted in ascending hash valuer order. */ -static int nondata_nodes_cmp(void *priv, struct list_head *a, - struct list_head *b) +static int nondata_nodes_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { ino_t inuma, inumb; struct ubifs_info *c = priv; diff --git a/fs/ubifs/replay.c b/fs/ubifs/replay.c index 0f8a6a16421b..4d17e5382b74 100644 --- a/fs/ubifs/replay.c +++ b/fs/ubifs/replay.c @@ -298,8 +298,8 @@ static int apply_replay_entry(struct ubifs_info *c, struct replay_entry *r) * entries @a and @b by comparing their sequence numer. Returns %1 if @a has * greater sequence number and %-1 otherwise. */ -static int replay_entries_cmp(void *priv, struct list_head *a, - struct list_head *b) +static int replay_entries_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct ubifs_info *c = priv; struct replay_entry *ra, *rb; diff --git a/fs/xfs/scrub/bitmap.c b/fs/xfs/scrub/bitmap.c index f88694f22d05..813b5f219113 100644 --- a/fs/xfs/scrub/bitmap.c +++ b/fs/xfs/scrub/bitmap.c @@ -63,8 +63,8 @@ xbitmap_init( static int xbitmap_range_cmp( void *priv, - struct list_head *a, - struct list_head *b) + const struct list_head *a, + const struct list_head *b) { struct xbitmap_range *ap; struct xbitmap_range *bp; diff --git a/fs/xfs/xfs_bmap_item.c b/fs/xfs/xfs_bmap_item.c index 2344757ede63..e3a691937e92 100644 --- a/fs/xfs/xfs_bmap_item.c +++ b/fs/xfs/xfs_bmap_item.c @@ -265,8 +265,8 @@ xfs_trans_log_finish_bmap_update( static int xfs_bmap_update_diff_items( void *priv, - struct list_head *a, - struct list_head *b) + const struct list_head *a, + const struct list_head *b) { struct xfs_bmap_intent *ba; struct xfs_bmap_intent *bb; diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c index 37a1d12762d8..592800c8852f 100644 --- a/fs/xfs/xfs_buf.c +++ b/fs/xfs/xfs_buf.c @@ -2124,9 +2124,9 @@ xfs_buf_delwri_queue( */ static int xfs_buf_cmp( - void *priv, - struct list_head *a, - struct list_head *b) + void *priv, + const struct list_head *a, + const struct list_head *b) { struct xfs_buf *ap = container_of(a, struct xfs_buf, b_list); struct xfs_buf *bp = container_of(b, struct xfs_buf, b_list); diff --git a/fs/xfs/xfs_extent_busy.c b/fs/xfs/xfs_extent_busy.c index ef17c1f6db32..a4075685d9eb 100644 --- a/fs/xfs/xfs_extent_busy.c +++ b/fs/xfs/xfs_extent_busy.c @@ -629,8 +629,8 @@ xfs_extent_busy_wait_all( int xfs_extent_busy_ag_cmp( void *priv, - struct list_head *l1, - struct list_head *l2) + const struct list_head *l1, + const struct list_head *l2) { struct xfs_extent_busy *b1 = container_of(l1, struct xfs_extent_busy, list); diff --git a/fs/xfs/xfs_extent_busy.h b/fs/xfs/xfs_extent_busy.h index 990ab3891971..8aea07100092 100644 --- a/fs/xfs/xfs_extent_busy.h +++ b/fs/xfs/xfs_extent_busy.h @@ -58,7 +58,8 @@ void xfs_extent_busy_wait_all(struct xfs_mount *mp); int -xfs_extent_busy_ag_cmp(void *priv, struct list_head *a, struct list_head *b); +xfs_extent_busy_ag_cmp(void *priv, const struct list_head *a, + const struct list_head *b); static inline void xfs_extent_busy_sort(struct list_head *list) { diff --git a/fs/xfs/xfs_extfree_item.c b/fs/xfs/xfs_extfree_item.c index 93223ebb3372..2424230ca2c3 100644 --- a/fs/xfs/xfs_extfree_item.c +++ b/fs/xfs/xfs_extfree_item.c @@ -397,8 +397,8 @@ xfs_trans_free_extent( static int xfs_extent_free_diff_items( void *priv, - struct list_head *a, - struct list_head *b) + const struct list_head *a, + const struct list_head *b) { struct xfs_mount *mp = priv; struct xfs_extent_free_item *ra; diff --git a/fs/xfs/xfs_refcount_item.c b/fs/xfs/xfs_refcount_item.c index 07ebccbbf4df..746f4eda724c 100644 --- a/fs/xfs/xfs_refcount_item.c +++ b/fs/xfs/xfs_refcount_item.c @@ -269,8 +269,8 @@ xfs_trans_log_finish_refcount_update( static int xfs_refcount_update_diff_items( void *priv, - struct list_head *a, - struct list_head *b) + const struct list_head *a, + const struct list_head *b) { struct xfs_mount *mp = priv; struct xfs_refcount_intent *ra; diff --git a/fs/xfs/xfs_rmap_item.c b/fs/xfs/xfs_rmap_item.c index 49cebd68b672..dc4f0c9f0897 100644 --- a/fs/xfs/xfs_rmap_item.c +++ b/fs/xfs/xfs_rmap_item.c @@ -337,8 +337,8 @@ xfs_trans_log_finish_rmap_update( static int xfs_rmap_update_diff_items( void *priv, - struct list_head *a, - struct list_head *b) + const struct list_head *a, + const struct list_head *b) { struct xfs_mount *mp = priv; struct xfs_rmap_intent *ra; diff --git a/include/linux/list_sort.h b/include/linux/list_sort.h index 20f178c24e9d..453105f74e05 100644 --- a/include/linux/list_sort.h +++ b/include/linux/list_sort.h @@ -6,8 +6,9 @@ struct list_head; +typedef int __attribute__((nonnull(2,3))) (*list_cmp_func_t)(void *, + const struct list_head *, const struct list_head *); + __attribute__((nonnull(2,3))) -void list_sort(void *priv, struct list_head *head, - int (*cmp)(void *priv, struct list_head *a, - struct list_head *b)); +void list_sort(void *priv, struct list_head *head, list_cmp_func_t cmp); #endif diff --git a/lib/list_sort.c b/lib/list_sort.c index 52f0c258c895..a926d96ffd44 100644 --- a/lib/list_sort.c +++ b/lib/list_sort.c @@ -7,16 +7,13 @@ #include #include -typedef int __attribute__((nonnull(2,3))) (*cmp_func)(void *, - struct list_head const *, struct list_head const *); - /* * Returns a list organized in an intermediate format suited * to chaining of merge() calls: null-terminated, no reserved or * sentinel head node, "prev" links not maintained. */ __attribute__((nonnull(2,3,4))) -static struct list_head *merge(void *priv, cmp_func cmp, +static struct list_head *merge(void *priv, list_cmp_func_t cmp, struct list_head *a, struct list_head *b) { struct list_head *head, **tail = &head; @@ -52,7 +49,7 @@ static struct list_head *merge(void *priv, cmp_func cmp, * throughout. */ __attribute__((nonnull(2,3,4,5))) -static void merge_final(void *priv, cmp_func cmp, struct list_head *head, +static void merge_final(void *priv, list_cmp_func_t cmp, struct list_head *head, struct list_head *a, struct list_head *b) { struct list_head *tail = head; @@ -185,9 +182,7 @@ static void merge_final(void *priv, cmp_func cmp, struct list_head *head, * 2^(k+1) - 1 (second merge of case 5 when x == 2^(k-1) - 1). */ __attribute__((nonnull(2,3))) -void list_sort(void *priv, struct list_head *head, - int (*cmp)(void *priv, struct list_head *a, - struct list_head *b)) +void list_sort(void *priv, struct list_head *head, list_cmp_func_t cmp) { struct list_head *list = head->next, *pending = NULL; size_t count = 0; /* Count of pending */ @@ -227,7 +222,7 @@ void list_sort(void *priv, struct list_head *head, if (likely(bits)) { struct list_head *a = *tail, *b = a->prev; - a = merge(priv, (cmp_func)cmp, b, a); + a = merge(priv, cmp, b, a); /* Install the merged result in place of the inputs */ a->prev = b->prev; *tail = a; @@ -249,10 +244,10 @@ void list_sort(void *priv, struct list_head *head, if (!next) break; - list = merge(priv, (cmp_func)cmp, pending, list); + list = merge(priv, cmp, pending, list); pending = next; } /* The final merge, rebuilding prev links */ - merge_final(priv, (cmp_func)cmp, head, pending, list); + merge_final(priv, cmp, head, pending, list); } EXPORT_SYMBOL(list_sort); diff --git a/lib/test_list_sort.c b/lib/test_list_sort.c index 1f017d3b610e..00daaf23316f 100644 --- a/lib/test_list_sort.c +++ b/lib/test_list_sort.c @@ -56,7 +56,8 @@ static int __init check(struct debug_el *ela, struct debug_el *elb) return 0; } -static int __init cmp(void *priv, struct list_head *a, struct list_head *b) +static int __init cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct debug_el *ela, *elb; diff --git a/net/tipc/name_table.c b/net/tipc/name_table.c index ee5ac40ea2b6..f8141443f2e2 100644 --- a/net/tipc/name_table.c +++ b/net/tipc/name_table.c @@ -397,8 +397,8 @@ static struct publication *tipc_service_remove_publ(struct service_range *sr, * Code reused: time_after32() for the same purpose */ #define publication_after(pa, pb) time_after32((pa)->id, (pb)->id) -static int tipc_publ_sort(void *priv, struct list_head *a, - struct list_head *b) +static int tipc_publ_sort(void *priv, const struct list_head *a, + const struct list_head *b) { struct publication *pa, *pb; 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Thu, 8 Apr 2021 14:29:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48760 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232918AbhDHS3j (ORCPT ); Thu, 8 Apr 2021 14:29:39 -0400 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6DAECC0613A8 for ; Thu, 8 Apr 2021 11:29:05 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id n67so2873231ybf.11 for ; Thu, 08 Apr 2021 11:29:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=A4KMkUZrl4YbLTqlF2GjjNGTYuxFr+/F8S0sGB79SBc=; b=rt9fOxKnB9y0igHfYBfQLlswurHVd9akIm8mQ7xCsufNWiBYdR3JhCpYM7Uax/eLvb Ihhz4rq6HcyX7REf0u2fqx7LVp4ukkmU+QC5NvoPcxJetx0GLnWLloqncFHy9GmoYMBn XjIhO8wNOL3YaZSw+9n6f8hcXwGNa5EVXVYOv+TLwmMSwMQDUKpz6OfnrIlesqFMkgkR XwLL5SN+XXLMayXhC5sCImEanWSuJTwkFWqMibje/hh2cGiFwv4rge6/fnMF/5m4/W6v 2KS84+T3ETJUQYWmacNH46sk/sKcVZ9rguitgtGIPddtwdEI5YDOujUYGBTToDSb8o4O GYVw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=A4KMkUZrl4YbLTqlF2GjjNGTYuxFr+/F8S0sGB79SBc=; b=QmYUebTAh5pYjihrd6M5XxouBd71nBZpvgDwK/p4IGtYljL71k5r3TyS4Ub5A2cRMB v8W/RB37RIMo8JEXDPFxUWXnLnPT5OMc0fYHzkWEsFJgzcQAQvxIURJBPSfN0Dc4pYh5 GDLLqfE4fn01alz3E91DH68HSh0LuCAy4cFRVgYrFKJ1thOlxIavXWorDSTQeeqL8Z5E QagtIkg40pj4Nja9QCqBedj6nxk2V93DLwVrVh5SWn6U3mJbwIwMfmRt5ZGHVZ3yQQX5 Qg6V1tTL2xuAH6P7mr9DaCtPLZy7gwdMoM2bhYauB66rE9e5eBCLiYET6X8X9iGWVRMr /fhg== X-Gm-Message-State: AOAM530u5rLI16C9+LTQ84MC6zunbdQ0UkMMPexTaNEfcCS9aeANv/mQ pzmYMDfc9KIk6rnIxFSxDo35A+CUI4Hyw+Ishj0= X-Google-Smtp-Source: ABdhPJy9XDHY4+uyYXn6KtdLMb9MXbOaRaW45MMiG7dZpwvMKLXKIxABytCBmfYEFzzpAYPpLEY0MfZ524rYOheFYP8= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:3560:8505:40a2:e021]) (user=samitolvanen job=sendgmr) by 2002:a25:ea44:: with SMTP id o4mr9706249ybe.506.1617906544646; Thu, 08 Apr 2021 11:29:04 -0700 (PDT) Date: Thu, 8 Apr 2021 11:28:35 -0700 In-Reply-To: <20210408182843.1754385-1-samitolvanen@google.com> Message-Id: <20210408182843.1754385-11-samitolvanen@google.com> Mime-Version: 1.0 References: <20210408182843.1754385-1-samitolvanen@google.com> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog Subject: [PATCH v6 10/18] lkdtm: use function_nocfi From: Sami Tolvanen To: Kees Cook Cc: Nathan Chancellor , Nick Desaulniers , Masahiro Yamada , Will Deacon , Jessica Yu , Arnd Bergmann , Tejun Heo , "Paul E. McKenney" , Christoph Hellwig , Peter Zijlstra , Sedat Dilek , Mark Rutland , Catalin Marinas , bpf@vger.kernel.org, linux-hardening@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org To ensure we take the actual address of a function in kernel text, use function_nocfi. Otherwise, with CONFIG_CFI_CLANG, the compiler replaces the address with a pointer to the CFI jump table, which is actually in the module when compiled with CONFIG_LKDTM=m. Signed-off-by: Sami Tolvanen Acked-by: Kees Cook Tested-by: Nathan Chancellor --- drivers/misc/lkdtm/usercopy.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/misc/lkdtm/usercopy.c b/drivers/misc/lkdtm/usercopy.c index 109e8d4302c1..15d220ef35a5 100644 --- a/drivers/misc/lkdtm/usercopy.c +++ b/drivers/misc/lkdtm/usercopy.c @@ -314,7 +314,7 @@ void lkdtm_USERCOPY_KERNEL(void) pr_info("attempting bad copy_to_user from kernel text: %px\n", vm_mmap); - if (copy_to_user((void __user *)user_addr, vm_mmap, + if (copy_to_user((void __user *)user_addr, function_nocfi(vm_mmap), unconst + PAGE_SIZE)) { pr_warn("copy_to_user failed, but lacked Oops\n"); goto free_user; From patchwork Thu Apr 8 18:28:36 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 12192195 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.2 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3AA8EC433ED for ; Thu, 8 Apr 2021 18:30:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0879561130 for ; Thu, 8 Apr 2021 18:30:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232999AbhDHSaW (ORCPT ); Thu, 8 Apr 2021 14:30:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48670 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232663AbhDHS3w (ORCPT ); Thu, 8 Apr 2021 14:29:52 -0400 Received: from mail-qk1-x74a.google.com (mail-qk1-x74a.google.com [IPv6:2607:f8b0:4864:20::74a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 61E0AC0613B1 for ; Thu, 8 Apr 2021 11:29:07 -0700 (PDT) Received: by mail-qk1-x74a.google.com with SMTP id o70so1829951qke.16 for ; Thu, 08 Apr 2021 11:29:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=14TYqH2ENqdx8tNGRNzk0x7BZIkRzbFF1Zb7Ap7y+mI=; b=HDvQ9PZApNfeAjnQLOW7KC9doRTIh6okNpM8589lZY+2eOjicKiTemkQkvkyQMeHdD oqBdomzQim+Gc97Fo+BScRDN/uYqxgD94hjnqyI+Uxo6rwKvcBXyVFo4/USMTXuzbxwk qg2hcRhzTn5P5aEl930+pnBiPB30eV6s3TB09qmkRDcTFIGeB4pMhNIe5+wTPuDDOlcm +CsRwIfaZFuSDD/U/wY75ESfG0GXmriI+0igXnIBdZIT0MPydBKVBLHEllZ6c/kE8ezI 2tbcU79LOWmnoiR/ReElL1+zVMaTX1hVUMai/MSNPX90NgepS5kimMBjIqCGhriW2448 Bj/w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=14TYqH2ENqdx8tNGRNzk0x7BZIkRzbFF1Zb7Ap7y+mI=; b=kHKOuGHcTPocmC7Sy1sbW6Eh6r2uDdUzoSWKf4bHR7fVnwixB7/FQQBNTpAPHvLZZk M+RyiRXN5RvrrZ0Os+5RrxZtxGW6bHE1dGPbIHd7mDCsWYSUygkipOMacik9cajBuPSb vbBNtxPZpsfS81LqmJ9QimMF+TEOLNYBztDWznI517ql3wunaBPK50O/dnsox4SK4gh5 eEV7IKNesBldKdfOkcUOTEfDQttH8yTdaN6M809JN2ejt7zn4TccB4a2Vhq49JZrDW+E 7w8bYU9A0/YO+rhSR8Sz/IL8wPheyMrWYmr+7Yd5fqiypkMBcUv+hG9ZPcxjc1m8vJOv jkUQ== X-Gm-Message-State: AOAM533vXwwJ+qqNY5hIw87nJ92/KxJGLG0OFZPZXMq7AYQQUUw1kkhE mAsG8mHjDxHg9t6mmD73p0pRlk34GqKqVeQi8Gc= X-Google-Smtp-Source: ABdhPJy2qIWEO5Ik0U4r4KHaXOyxsSt8UhM0F/UOsH1W4SX+8Ypg74UJD6u6iBTGlhqMo2VQnRoSFME0VEY+S6wlQTM= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:3560:8505:40a2:e021]) (user=samitolvanen job=sendgmr) by 2002:a0c:f605:: with SMTP id r5mr10061255qvm.48.1617906546551; Thu, 08 Apr 2021 11:29:06 -0700 (PDT) Date: Thu, 8 Apr 2021 11:28:36 -0700 In-Reply-To: <20210408182843.1754385-1-samitolvanen@google.com> Message-Id: <20210408182843.1754385-12-samitolvanen@google.com> Mime-Version: 1.0 References: <20210408182843.1754385-1-samitolvanen@google.com> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog Subject: [PATCH v6 11/18] psci: use function_nocfi for cpu_resume From: Sami Tolvanen To: Kees Cook Cc: Nathan Chancellor , Nick Desaulniers , Masahiro Yamada , Will Deacon , Jessica Yu , Arnd Bergmann , Tejun Heo , "Paul E. McKenney" , Christoph Hellwig , Peter Zijlstra , Sedat Dilek , Mark Rutland , Catalin Marinas , bpf@vger.kernel.org, linux-hardening@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org With CONFIG_CFI_CLANG, the compiler replaces function pointers with jump table addresses, which results in __pa_symbol returning the physical address of the jump table entry. As the jump table contains an immediate jump to an EL1 virtual address, this typically won't work as intended. Use function_nocfi to get the actual address of cpu_resume. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Acked-by: Mark Rutland Tested-by: Nathan Chancellor --- drivers/firmware/psci/psci.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c index f5fc429cae3f..64344e84bd63 100644 --- a/drivers/firmware/psci/psci.c +++ b/drivers/firmware/psci/psci.c @@ -325,8 +325,9 @@ static int __init psci_features(u32 psci_func_id) static int psci_suspend_finisher(unsigned long state) { u32 power_state = state; + phys_addr_t pa_cpu_resume = __pa_symbol(function_nocfi(cpu_resume)); - return psci_ops.cpu_suspend(power_state, __pa_symbol(cpu_resume)); + return psci_ops.cpu_suspend(power_state, pa_cpu_resume); } int psci_cpu_suspend_enter(u32 state) @@ -344,8 +345,10 @@ int psci_cpu_suspend_enter(u32 state) static int psci_system_suspend(unsigned long unused) { + phys_addr_t pa_cpu_resume = __pa_symbol(function_nocfi(cpu_resume)); + return invoke_psci_fn(PSCI_FN_NATIVE(1_0, SYSTEM_SUSPEND), - __pa_symbol(cpu_resume), 0, 0); + pa_cpu_resume, 0, 0); } static int psci_system_suspend_enter(suspend_state_t state) From patchwork Thu Apr 8 18:28:37 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 12192197 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.2 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C7FBEC43470 for ; Thu, 8 Apr 2021 18:30:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A9F586113A for ; Thu, 8 Apr 2021 18:30:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232915AbhDHSaZ (ORCPT ); Thu, 8 Apr 2021 14:30:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48734 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233011AbhDHS34 (ORCPT ); Thu, 8 Apr 2021 14:29:56 -0400 Received: from mail-qt1-x849.google.com (mail-qt1-x849.google.com [IPv6:2607:f8b0:4864:20::849]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3809AC0613B5 for ; Thu, 8 Apr 2021 11:29:09 -0700 (PDT) Received: by mail-qt1-x849.google.com with SMTP id h22so1037045qtb.6 for ; Thu, 08 Apr 2021 11:29:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=Rfpjk5lcXiQmXeSx6i4pVVD3rq5mJRtqi0n+qpZr8Ec=; b=uxzGce9H+bQxI3BH5eSnZL/WitMYUsWyiXWRdxtpao5coAXNqK6ECiPrZVE6VXKF2d CFnPSiZQdP6yjcairauODzoA9soSLiJLebgkNNcL2BAyF5MUxAS7P5C4M86UUGzfgPQV LOCPp0ihlS3AG2ENC7WGpgFjZTY5txSczvxDjD7tmVSfQbZ5P9Ym4yOL6BmQy3mZAV+X +6IUfO3iU/PRlH4C6yevg8ke5hfllIcxkEb6BySdOrds6Wpbm3ZPy5IL7Q0UKBS/950R EoKMmBaAN4rDGa+BOE83OyIhGGRij4llD8VaQ6C/cDMFpzuzbYDBUJ8/H9t9SIp+2du0 TTzQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=Rfpjk5lcXiQmXeSx6i4pVVD3rq5mJRtqi0n+qpZr8Ec=; b=H7tgwUS9AE/cm0A/bXX//co3GGTi806zDErduXPCt6boXsjJqPBN0NJvGqQDPDDAEK g4tJA+6d2ZhZd5/qNYj5PKfGmCBHNbugCxKxRGFANqhUnfB4HMZD/KIluzV2ms5DfRWV jIusnAbW5uAMttcfL/Xu3BKCe/9xJQ2WXTaj9vmyRQzD00XHZxBso8YtaHCPt88lcE/Y qt4lD4xBHJiiE9uzULQje6tJhUpJDBMSpdhFeBSnnxFkTqiAKGvmmmaziQ08DKOKvtIO mO9jJ2gHTaHue/Qtd+u8fEAF/o4ppgn5QaraB5B6BG72IPZU+yK/sAfFt3nka+GR/7YD LkaA== X-Gm-Message-State: AOAM53170FNnRbOpNWRtvKDYY6UvnM8OJ/4qtcYwrrXG1Aj729xIDC3K o++hEGmmzbsWxWQZxJQ3rBt8lAGdqPctkkYhh3I= X-Google-Smtp-Source: ABdhPJykkCoAAlAuPh9UWpRW+zA8QhzqRpVC9BlGLOFGa1L0GzjX44pUdqjjGr9/CGnpUy9ZPsJOE4srXjI5kf/aoHk= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:3560:8505:40a2:e021]) (user=samitolvanen job=sendgmr) by 2002:a0c:e84e:: with SMTP id l14mr10480012qvo.39.1617906548385; Thu, 08 Apr 2021 11:29:08 -0700 (PDT) Date: Thu, 8 Apr 2021 11:28:37 -0700 In-Reply-To: <20210408182843.1754385-1-samitolvanen@google.com> Message-Id: <20210408182843.1754385-13-samitolvanen@google.com> Mime-Version: 1.0 References: <20210408182843.1754385-1-samitolvanen@google.com> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog Subject: [PATCH v6 12/18] arm64: implement function_nocfi From: Sami Tolvanen To: Kees Cook Cc: Nathan Chancellor , Nick Desaulniers , Masahiro Yamada , Will Deacon , Jessica Yu , Arnd Bergmann , Tejun Heo , "Paul E. McKenney" , Christoph Hellwig , Peter Zijlstra , Sedat Dilek , Mark Rutland , Catalin Marinas , bpf@vger.kernel.org, linux-hardening@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org With CONFIG_CFI_CLANG, the compiler replaces function addresses in instrumented C code with jump table addresses. This change implements the function_nocfi() macro, which returns the actual function address instead. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Acked-by: Mark Rutland Tested-by: Nathan Chancellor --- arch/arm64/include/asm/memory.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h index 0aabc3be9a75..3a6f9df63606 100644 --- a/arch/arm64/include/asm/memory.h +++ b/arch/arm64/include/asm/memory.h @@ -321,6 +321,22 @@ static inline void *phys_to_virt(phys_addr_t x) #define virt_to_pfn(x) __phys_to_pfn(__virt_to_phys((unsigned long)(x))) #define sym_to_pfn(x) __phys_to_pfn(__pa_symbol(x)) +#ifdef CONFIG_CFI_CLANG +/* + * With CONFIG_CFI_CLANG, the compiler replaces function address + * references with the address of the function's CFI jump table + * entry. The function_nocfi macro always returns the address of the + * actual function instead. + */ +#define function_nocfi(x) ({ \ + void *addr; \ + asm("adrp %0, " __stringify(x) "\n\t" \ + "add %0, %0, :lo12:" __stringify(x) \ + : "=r" (addr)); \ + addr; \ +}) +#endif + /* * virt_to_page(x) convert a _valid_ virtual address to struct page * * virt_addr_valid(x) indicates whether a virtual address is valid From patchwork Thu Apr 8 18:28:38 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 12192199 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.2 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 182D3C4360C for ; Thu, 8 Apr 2021 18:30:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EFF1061132 for ; Thu, 8 Apr 2021 18:30:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233011AbhDHSa0 (ORCPT ); Thu, 8 Apr 2021 14:30:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48692 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232866AbhDHS37 (ORCPT ); Thu, 8 Apr 2021 14:29:59 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 276F5C0613DC for ; Thu, 8 Apr 2021 11:29:11 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id 131so2862349ybp.16 for ; Thu, 08 Apr 2021 11:29:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=YjeJV8buzrz7V/Fei1ZZdYKcpdw6OH5oq1m6MHRvYmA=; b=v/SKTB1wC3jPizkKDMqxqoKm8JBsnHMb3V89BEumYlVpdhhEiRe+pjAmo6I5FqynU8 BxUQazKPK3vtO2uqCca1Wl5bOyBQK1LOLIgMPfV4qDMLeqTeQREY+HKJ5z2YNFd516IR Uc1OZ9qlz08gx/ejNcytyVZ7xNx8ridbKmiNvCOVYAKSu6nOn62N1AIdYI5g825VAPl/ 0m7DrTs5lzXT9lrzp6nDTNrBPjuzpJda9D3+kWA63RP3IiEUJK5UpPL2ysFDJ6xJmOIg XaA5uPdBZQnoyh1YIcSDB+RQ8R6kYF6Emr4JkBNKiDpsBFkzFogjdZxwtALGSUN2SFKW ndDQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=YjeJV8buzrz7V/Fei1ZZdYKcpdw6OH5oq1m6MHRvYmA=; b=lSOlOYt2RQp4c10wrC0Oq+DAoyPu8X8HZqkxEF1W9A3HPrpvgBzlTEf9vpouoOitt+ cqhW7jIuHOiTlnOiPfGMdojQQ9Wa0aWQw8hu/81McCAP9J5z4MA7k/mVcoBz5AKEsB6S kCRrjJT8w9lz2vCxUKhfA7fSV7QHep6s822PZFBY7IYHAV1LBelgB7KpZbE3V0LGfGcZ w4AFwGblog7kT17M++niEvv6EmkFLeqP6AD1bCEw5i7utr+cnPNLp05j1sLMwrk77Th1 B8MrNob02UsjmB3gg8RK68QH+P9B9GMRfQD4jnxjyAKv1fSjBRxepTr6SR90jde0Dq6s wwug== X-Gm-Message-State: AOAM533xl0j+J5y6cIE5Ne6VwnrrLtFl7GP1NBWKGVmRPS9MEteCV6XG lqoPO7gTB8SOGK/a1FkCmUW6q7fkneiX34bqXQ8= X-Google-Smtp-Source: ABdhPJzm6pdKlFzf5PWHu4bUzusCbWOAn93ewk4Srt7AdZyHa2tCRz8rO0ngS/HvlZRA63qxtBMVoCdOuDKqfxzBxvs= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:3560:8505:40a2:e021]) (user=samitolvanen job=sendgmr) by 2002:a25:a42a:: with SMTP id f39mr13864946ybi.414.1617906550366; Thu, 08 Apr 2021 11:29:10 -0700 (PDT) Date: Thu, 8 Apr 2021 11:28:38 -0700 In-Reply-To: <20210408182843.1754385-1-samitolvanen@google.com> Message-Id: <20210408182843.1754385-14-samitolvanen@google.com> Mime-Version: 1.0 References: <20210408182843.1754385-1-samitolvanen@google.com> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog Subject: [PATCH v6 13/18] arm64: use function_nocfi with __pa_symbol From: Sami Tolvanen To: Kees Cook Cc: Nathan Chancellor , Nick Desaulniers , Masahiro Yamada , Will Deacon , Jessica Yu , Arnd Bergmann , Tejun Heo , "Paul E. McKenney" , Christoph Hellwig , Peter Zijlstra , Sedat Dilek , Mark Rutland , Catalin Marinas , bpf@vger.kernel.org, linux-hardening@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org With CONFIG_CFI_CLANG, the compiler replaces function address references with the address of the function's CFI jump table entry. This means that __pa_symbol(function) returns the physical address of the jump table entry, which can lead to address space confusion as the jump table points to the function's virtual address. Therefore, use the function_nocfi() macro to ensure we are always taking the address of the actual function instead. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Acked-by: Mark Rutland Tested-by: Nathan Chancellor --- arch/arm64/include/asm/mmu_context.h | 2 +- arch/arm64/kernel/acpi_parking_protocol.c | 3 ++- arch/arm64/kernel/cpu-reset.h | 2 +- arch/arm64/kernel/cpufeature.c | 2 +- arch/arm64/kernel/psci.c | 3 ++- arch/arm64/kernel/smp_spin_table.c | 3 ++- 6 files changed, 9 insertions(+), 6 deletions(-) diff --git a/arch/arm64/include/asm/mmu_context.h b/arch/arm64/include/asm/mmu_context.h index bd02e99b1a4c..386b96400a57 100644 --- a/arch/arm64/include/asm/mmu_context.h +++ b/arch/arm64/include/asm/mmu_context.h @@ -140,7 +140,7 @@ static inline void cpu_replace_ttbr1(pgd_t *pgdp) ttbr1 |= TTBR_CNP_BIT; } - replace_phys = (void *)__pa_symbol(idmap_cpu_replace_ttbr1); + replace_phys = (void *)__pa_symbol(function_nocfi(idmap_cpu_replace_ttbr1)); cpu_install_idmap(); replace_phys(ttbr1); diff --git a/arch/arm64/kernel/acpi_parking_protocol.c b/arch/arm64/kernel/acpi_parking_protocol.c index e7c941d8340d..bfeeb5319abf 100644 --- a/arch/arm64/kernel/acpi_parking_protocol.c +++ b/arch/arm64/kernel/acpi_parking_protocol.c @@ -99,7 +99,8 @@ static int acpi_parking_protocol_cpu_boot(unsigned int cpu) * that read this address need to convert this address to the * Boot-Loader's endianness before jumping. */ - writeq_relaxed(__pa_symbol(secondary_entry), &mailbox->entry_point); + writeq_relaxed(__pa_symbol(function_nocfi(secondary_entry)), + &mailbox->entry_point); writel_relaxed(cpu_entry->gic_cpu_id, &mailbox->cpu_id); arch_send_wakeup_ipi_mask(cpumask_of(cpu)); diff --git a/arch/arm64/kernel/cpu-reset.h b/arch/arm64/kernel/cpu-reset.h index ed50e9587ad8..f3adc574f969 100644 --- a/arch/arm64/kernel/cpu-reset.h +++ b/arch/arm64/kernel/cpu-reset.h @@ -22,7 +22,7 @@ static inline void __noreturn cpu_soft_restart(unsigned long entry, unsigned long el2_switch = !is_kernel_in_hyp_mode() && is_hyp_mode_available(); - restart = (void *)__pa_symbol(__cpu_soft_restart); + restart = (void *)__pa_symbol(function_nocfi(__cpu_soft_restart)); cpu_install_idmap(); restart(el2_switch, entry, arg0, arg1, arg2); diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index e5281e1c8f1d..0b2e0d7b13ec 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -1462,7 +1462,7 @@ kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused) if (arm64_use_ng_mappings) return; - remap_fn = (void *)__pa_symbol(idmap_kpti_install_ng_mappings); + remap_fn = (void *)__pa_symbol(function_nocfi(idmap_kpti_install_ng_mappings)); cpu_install_idmap(); remap_fn(cpu, num_online_cpus(), __pa_symbol(swapper_pg_dir)); diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c index 62d2bda7adb8..ab7f4c476104 100644 --- a/arch/arm64/kernel/psci.c +++ b/arch/arm64/kernel/psci.c @@ -38,7 +38,8 @@ static int __init cpu_psci_cpu_prepare(unsigned int cpu) static int cpu_psci_cpu_boot(unsigned int cpu) { - int err = psci_ops.cpu_on(cpu_logical_map(cpu), __pa_symbol(secondary_entry)); + phys_addr_t pa_secondary_entry = __pa_symbol(function_nocfi(secondary_entry)); + int err = psci_ops.cpu_on(cpu_logical_map(cpu), pa_secondary_entry); if (err) pr_err("failed to boot CPU%d (%d)\n", cpu, err); diff --git a/arch/arm64/kernel/smp_spin_table.c b/arch/arm64/kernel/smp_spin_table.c index 056772c26098..c45a83512805 100644 --- a/arch/arm64/kernel/smp_spin_table.c +++ b/arch/arm64/kernel/smp_spin_table.c @@ -66,6 +66,7 @@ static int smp_spin_table_cpu_init(unsigned int cpu) static int smp_spin_table_cpu_prepare(unsigned int cpu) { __le64 __iomem *release_addr; + phys_addr_t pa_holding_pen = __pa_symbol(function_nocfi(secondary_holding_pen)); if (!cpu_release_addr[cpu]) return -ENODEV; @@ -88,7 +89,7 @@ static int smp_spin_table_cpu_prepare(unsigned int cpu) * boot-loader's endianness before jumping. This is mandated by * the boot protocol. */ - writeq_relaxed(__pa_symbol(secondary_holding_pen), release_addr); + writeq_relaxed(pa_holding_pen, release_addr); __flush_dcache_area((__force void *)release_addr, sizeof(*release_addr)); From patchwork Thu Apr 8 18:28:39 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 12192201 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.2 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 74791C433B4 for ; Thu, 8 Apr 2021 18:30:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 56AF7610FC for ; Thu, 8 Apr 2021 18:30:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232977AbhDHSal (ORCPT ); Thu, 8 Apr 2021 14:30:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48666 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232976AbhDHSaM (ORCPT ); Thu, 8 Apr 2021 14:30:12 -0400 Received: from mail-qt1-x849.google.com (mail-qt1-x849.google.com [IPv6:2607:f8b0:4864:20::849]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 59F86C0613BA for ; Thu, 8 Apr 2021 11:29:13 -0700 (PDT) Received: by mail-qt1-x849.google.com with SMTP id g7so1639066qtb.5 for ; Thu, 08 Apr 2021 11:29:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=aJ78CQ4sSObE7h7fKH9+1A4v2ZQnllJDRyYlzc3oTAI=; b=MHjorWaA9cqvjCV1vLFpiSODDJWp3DQrVr2AHYq3txbWEysIHt9DUSzoMYUvoFyANG E2C705jG2SEZGcLkMefsBeVjl3wLzBqgwpD053sTrvgwghJfmLhARQ/Y9cAOH4zTIRgg Gx1r77cLJDEb9EOhk+dsk/h50X+ReYAXEPVNzcfFL5m5rUHdBidHwgD67eM3rDMgIwa+ mVr2AN3P4KLVWVDm23HpWWvGdT4AwMifN6Qxcedd+js8rkQe2M3PR+szlpqn3xw98X3j tyShTpdkqo9lSd6l7hHO0TlARnATWf7l1D7Ome4WRCmkgOycQrmmZ+SFbWSvpnm8v6Ov qLxg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=aJ78CQ4sSObE7h7fKH9+1A4v2ZQnllJDRyYlzc3oTAI=; b=G0/t1YMzepskEQ8rKnN9rY8mLhKSALtUHfw7aQRYeSFgFiibH+6n7V8GQ4+gThDFRp 24Iegx5UmZ/MJrkkUEc/Cl225ffUd5hSqq84m29rsHe7F1rgAoTShoNt+0aJS3tQ9F2C 9MC78NsniyGPK+dEdddDsxxeNkBGnGTNGbwfrq2Y3xlNWtq9UsuS7gw9R/pPY+ySath9 3aOIKVrSFlTGoJ9CObIm6qb1uE6uOnRMf+XIH31NyHgcEx06tSK04tRzYdmL1LPxaI72 68IJre7PjuMCyO8x4CzEtb3dMoZRbZtqOsz+mzMaz4nTYnXVTIT5TJfy1rQXlNCix4DD 826g== X-Gm-Message-State: AOAM533Uxx6tgAUB1QvRQpavgjoX9w2y+T2W8fTL2AmVj89fN+Y8WhyT OjIB257yL1IVmdbbwK0VmavJ/GdBkMIPUGg37cI= X-Google-Smtp-Source: ABdhPJzwVTQdAK5UkhD1PnR2Qb9dWptcs9iybmVqXLD+eWKEqS2UHPDLF0diVVB2LF9LH4/E2DAQ5mXPMjPNEy9u9ic= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:3560:8505:40a2:e021]) (user=samitolvanen job=sendgmr) by 2002:a0c:e3d0:: with SMTP id e16mr9980885qvl.1.1617906552307; Thu, 08 Apr 2021 11:29:12 -0700 (PDT) Date: Thu, 8 Apr 2021 11:28:39 -0700 In-Reply-To: <20210408182843.1754385-1-samitolvanen@google.com> Message-Id: <20210408182843.1754385-15-samitolvanen@google.com> Mime-Version: 1.0 References: <20210408182843.1754385-1-samitolvanen@google.com> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog Subject: [PATCH v6 14/18] arm64: add __nocfi to functions that jump to a physical address From: Sami Tolvanen To: Kees Cook Cc: Nathan Chancellor , Nick Desaulniers , Masahiro Yamada , Will Deacon , Jessica Yu , Arnd Bergmann , Tejun Heo , "Paul E. McKenney" , Christoph Hellwig , Peter Zijlstra , Sedat Dilek , Mark Rutland , Catalin Marinas , bpf@vger.kernel.org, linux-hardening@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org Disable CFI checking for functions that switch to linear mapping and make an indirect call to a physical address, since the compiler only understands virtual addresses and the CFI check for such indirect calls would always fail. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Tested-by: Nathan Chancellor --- arch/arm64/include/asm/mmu_context.h | 2 +- arch/arm64/kernel/cpu-reset.h | 8 ++++---- arch/arm64/kernel/cpufeature.c | 2 +- 3 files changed, 6 insertions(+), 6 deletions(-) diff --git a/arch/arm64/include/asm/mmu_context.h b/arch/arm64/include/asm/mmu_context.h index 386b96400a57..d3cef9133539 100644 --- a/arch/arm64/include/asm/mmu_context.h +++ b/arch/arm64/include/asm/mmu_context.h @@ -119,7 +119,7 @@ static inline void cpu_install_idmap(void) * Atomically replaces the active TTBR1_EL1 PGD with a new VA-compatible PGD, * avoiding the possibility of conflicting TLB entries being allocated. */ -static inline void cpu_replace_ttbr1(pgd_t *pgdp) +static inline void __nocfi cpu_replace_ttbr1(pgd_t *pgdp) { typedef void (ttbr_replace_func)(phys_addr_t); extern ttbr_replace_func idmap_cpu_replace_ttbr1; diff --git a/arch/arm64/kernel/cpu-reset.h b/arch/arm64/kernel/cpu-reset.h index f3adc574f969..9a7b1262ef17 100644 --- a/arch/arm64/kernel/cpu-reset.h +++ b/arch/arm64/kernel/cpu-reset.h @@ -13,10 +13,10 @@ void __cpu_soft_restart(unsigned long el2_switch, unsigned long entry, unsigned long arg0, unsigned long arg1, unsigned long arg2); -static inline void __noreturn cpu_soft_restart(unsigned long entry, - unsigned long arg0, - unsigned long arg1, - unsigned long arg2) +static inline void __noreturn __nocfi cpu_soft_restart(unsigned long entry, + unsigned long arg0, + unsigned long arg1, + unsigned long arg2) { typeof(__cpu_soft_restart) *restart; diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 0b2e0d7b13ec..c2f94a5206e0 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -1445,7 +1445,7 @@ static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry, } #ifdef CONFIG_UNMAP_KERNEL_AT_EL0 -static void +static void __nocfi kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused) { typedef void (kpti_remap_fn)(int, int, phys_addr_t); From patchwork Thu Apr 8 18:28:40 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 12192203 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.2 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3FF52C43460 for ; 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Thu, 08 Apr 2021 11:29:14 -0700 (PDT) Date: Thu, 8 Apr 2021 11:28:40 -0700 In-Reply-To: <20210408182843.1754385-1-samitolvanen@google.com> Message-Id: <20210408182843.1754385-16-samitolvanen@google.com> Mime-Version: 1.0 References: <20210408182843.1754385-1-samitolvanen@google.com> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog Subject: [PATCH v6 15/18] arm64: add __nocfi to __apply_alternatives From: Sami Tolvanen To: Kees Cook Cc: Nathan Chancellor , Nick Desaulniers , Masahiro Yamada , Will Deacon , Jessica Yu , Arnd Bergmann , Tejun Heo , "Paul E. McKenney" , Christoph Hellwig , Peter Zijlstra , Sedat Dilek , Mark Rutland , Catalin Marinas , bpf@vger.kernel.org, linux-hardening@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org __apply_alternatives makes indirect calls to functions whose address is taken in assembly code using the alternative_cb macro. With non-canonical CFI, the compiler won't replace these function references with the jump table addresses, which trips CFI. Disable CFI checking in the function to work around the issue. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Tested-by: Nathan Chancellor --- arch/arm64/kernel/alternative.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kernel/alternative.c b/arch/arm64/kernel/alternative.c index 1184c44ea2c7..abc84636af07 100644 --- a/arch/arm64/kernel/alternative.c +++ b/arch/arm64/kernel/alternative.c @@ -133,8 +133,8 @@ static void clean_dcache_range_nopatch(u64 start, u64 end) } while (cur += d_size, cur < end); } -static void __apply_alternatives(void *alt_region, bool is_module, - unsigned long *feature_mask) +static void __nocfi __apply_alternatives(void *alt_region, bool is_module, + unsigned long *feature_mask) { struct alt_instr *alt; struct alt_region *region = alt_region; From patchwork Thu Apr 8 18:28:41 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 12192205 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.2 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 11FC9C433B4 for ; Thu, 8 Apr 2021 18:30:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D487461130 for ; Thu, 8 Apr 2021 18:30:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233081AbhDHSa4 (ORCPT ); Thu, 8 Apr 2021 14:30:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48656 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232955AbhDHSaZ (ORCPT ); Thu, 8 Apr 2021 14:30:25 -0400 Received: from mail-pl1-x64a.google.com (mail-pl1-x64a.google.com [IPv6:2607:f8b0:4864:20::64a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0CB30C0611A3 for ; Thu, 8 Apr 2021 11:29:17 -0700 (PDT) Received: by mail-pl1-x64a.google.com with SMTP id z1so1301731plg.14 for ; Thu, 08 Apr 2021 11:29:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=E//9MgjgyGyGzfpqyqWq2doSFEPDUmVLoRf38lFR7Ug=; b=RkrEMcjEGks9eZDKQu+2cXBVixhfRtfNzurKOb7kj5G0lHbsNG+kVYT00dZ5fCwZZm oGJ3H14LgsxmvSmAONHP3AD4DqcsZiijiViY54PVPWASyhlBWJKul0uk2D6FHPy5MGCI hRwVaWPtPODb24A1fAYvc3Pk8kJw73Wgq0qpJVjB3nsOpeMmHe8UyFYE027vmCmfDH59 TeMeJF97gfJcV1bR86XXNmc9WzLb/xoI5eyDhzlmA3A8LFSbl+CVN1qG+Ng6f1ydMu6m HP+jBZVA3ShA+iChc9OSbbyum7a0Xu8+WCER3+MJXJ4MzHQMgKZMSbyX49ZilNruBraI +ZqQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=E//9MgjgyGyGzfpqyqWq2doSFEPDUmVLoRf38lFR7Ug=; b=f013xZ1ibuC5x5CmcoNE3s2n+vZ1IiYk8vQ5M7FEfI7hN5R1jMKH6lCDiQse5HMNRU H1nF8GYuw9PO2LwMmuzlyL5WgxpVFU79y7mbirKzwgEpudDXS2c06I/1t1WQmPsZCVYM O3mIymxXBmIob4fIWSUmFdF/W0HdKDjcEleXhrbsLcmEGyqpugsF/5uqL2Roh67Yu3co SgWWe+JEo6Z2BcgDwCfpSXPYFZALGpGnBtukZdIDizDfuH9K7MppJjGxpRkmk4uOiXST 208wLzAqCz0ifAysEmlyOhtMiHPD9XVdvuy+FV03yOQ7k9It0hKaaao4vhiUdlDF13Ry 8MPA== X-Gm-Message-State: AOAM531s4FVIdMxAFbwVnK8g1laTILJ5b3LYLJZJiblzBeL9hKlWX7Ii CW3dDY+FWJOw1gXXTzDW6dpE2t/6/Oku+rM9eg4= X-Google-Smtp-Source: ABdhPJxklicbJf72RxeJ+L/uYgGqphrH56F65dx6SJ8/fgnDi6ps2xo+6HGcUO7vtPk7NlHN1dleq0bA9WeA14sn2Uk= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:3560:8505:40a2:e021]) (user=samitolvanen job=sendgmr) by 2002:a17:902:7896:b029:e8:fa73:ad22 with SMTP id q22-20020a1709027896b02900e8fa73ad22mr8974621pll.66.1617906556287; Thu, 08 Apr 2021 11:29:16 -0700 (PDT) Date: Thu, 8 Apr 2021 11:28:41 -0700 In-Reply-To: <20210408182843.1754385-1-samitolvanen@google.com> Message-Id: <20210408182843.1754385-17-samitolvanen@google.com> Mime-Version: 1.0 References: <20210408182843.1754385-1-samitolvanen@google.com> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog Subject: [PATCH v6 16/18] arm64: ftrace: use function_nocfi for ftrace_call From: Sami Tolvanen To: Kees Cook Cc: Nathan Chancellor , Nick Desaulniers , Masahiro Yamada , Will Deacon , Jessica Yu , Arnd Bergmann , Tejun Heo , "Paul E. McKenney" , Christoph Hellwig , Peter Zijlstra , Sedat Dilek , Mark Rutland , Catalin Marinas , bpf@vger.kernel.org, linux-hardening@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org With CONFIG_CFI_CLANG, the compiler replaces function pointers with jump table addresses, which breaks dynamic ftrace as the address of ftrace_call is replaced with the address of ftrace_call.cfi_jt. Use function_nocfi() to get the address of the actual function instead. Suggested-by: Ben Dai Signed-off-by: Sami Tolvanen Acked-by: Mark Rutland Tested-by: Nathan Chancellor --- arch/arm64/kernel/ftrace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c index 86a5cf9bc19a..b5d3ddaf69d9 100644 --- a/arch/arm64/kernel/ftrace.c +++ b/arch/arm64/kernel/ftrace.c @@ -55,7 +55,7 @@ int ftrace_update_ftrace_func(ftrace_func_t func) unsigned long pc; u32 new; - pc = (unsigned long)&ftrace_call; + pc = (unsigned long)function_nocfi(ftrace_call); new = aarch64_insn_gen_branch_imm(pc, (unsigned long)func, AARCH64_INSN_BRANCH_LINK); From patchwork Thu Apr 8 18:28:42 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 12192207 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.2 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DE49EC43462 for ; Thu, 8 Apr 2021 18:30:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B3F426115B for ; Thu, 8 Apr 2021 18:30:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233043AbhDHSbF (ORCPT ); Thu, 8 Apr 2021 14:31:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48700 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232944AbhDHSak (ORCPT ); Thu, 8 Apr 2021 14:30:40 -0400 Received: from mail-qk1-x749.google.com (mail-qk1-x749.google.com [IPv6:2607:f8b0:4864:20::749]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2C7CAC0613E3 for ; Thu, 8 Apr 2021 11:29:19 -0700 (PDT) Received: by mail-qk1-x749.google.com with SMTP id p133so1825065qka.17 for ; Thu, 08 Apr 2021 11:29:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=/RFtNNq4R+HQlfABCrnOp0vGXtCZ+PdK4tYVAs3Xgq4=; b=mRyvx1ZyCWRRYs/gtfFKoK8RBt3UI3Cbe8UFU+DjhbwvArNTuLgIFS5sSHA8GrypJO h1Ut4lnsHPkWI+6YGudQiUwKpMvE3rw3IvXbMyabZSfdvOVUtUOuttrRv/lU1I0YKtr+ 2KHbgG7VEZaD7k90Q2eC5FYoEypvPzIMBzhRBoMcW7o/u3O1niG3LYNNqbDjD1qMFVl5 E0r5iFj/NMKIiwFuIz+tbBcn4ksbC5mZayHEJv3FtIIufUIqISS2/csUEuPKce6VPJ6v 9VVELn3ltJVZx2tcvPVhDFYkynJ6q1lEl6xzivgPR/q2vDBkBfPrFKC+an1ZU7XkvHYL wK7w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=/RFtNNq4R+HQlfABCrnOp0vGXtCZ+PdK4tYVAs3Xgq4=; b=pqIm5XQtBd9pttnsk9qprh9CFUVm197+M/8aJOGOwMfi9h260sRZwC9/77VCvWU7L9 yWt3cBZaQicG8F4tqJhVL7WnkHbdZTzB4M4RHvXH1jalJ7hGsQ25yYbrl3VkveFrtLZI WnFjHpSM4/4xsMs2ke3qiizFuqKHRrj5aYWrixUXNVlPSrUonh01jXfdwtJut5B4fFzY FZ7hjUPsEz4nUZsB+DUOv9ePYI1KjqXaclgi5MjRbVND5yI+oyWmKehXabfH1vQBgb/F fPIk9U09crUIJ1f3KPqZgOKTTYklHb1B7DkVLG6PAtcSf7hSd8L6Rtk70SSYaUUs37hJ uObQ== X-Gm-Message-State: AOAM5308SICpwnd6wsm0d6B3Dk8dIJaLda/Svv6ba9amjC84Ev7Lf/ra 4RsVuuVTHWdjAa9hP3gBGgQBUT5eZWzdyfztNKs= X-Google-Smtp-Source: ABdhPJx0EQDE5MZTKE/yaW2uV6UWZxJCkACiU6S0cyy4tgm6Rm995yl/yaBcL1JmqZoeGYIAcOfNaP46VqXvbu6lWB8= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:3560:8505:40a2:e021]) (user=samitolvanen job=sendgmr) by 2002:a0c:b410:: with SMTP id u16mr10174868qve.8.1617906558331; Thu, 08 Apr 2021 11:29:18 -0700 (PDT) Date: Thu, 8 Apr 2021 11:28:42 -0700 In-Reply-To: <20210408182843.1754385-1-samitolvanen@google.com> Message-Id: <20210408182843.1754385-18-samitolvanen@google.com> Mime-Version: 1.0 References: <20210408182843.1754385-1-samitolvanen@google.com> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog Subject: [PATCH v6 17/18] KVM: arm64: Disable CFI for nVHE From: Sami Tolvanen To: Kees Cook Cc: Nathan Chancellor , Nick Desaulniers , Masahiro Yamada , Will Deacon , Jessica Yu , Arnd Bergmann , Tejun Heo , "Paul E. McKenney" , Christoph Hellwig , Peter Zijlstra , Sedat Dilek , Mark Rutland , Catalin Marinas , bpf@vger.kernel.org, linux-hardening@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org Disable CFI for the nVHE code to avoid address space confusion. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Tested-by: Nathan Chancellor --- arch/arm64/kvm/hyp/nvhe/Makefile | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile index a6707df4f6c0..fb24a0f022ad 100644 --- a/arch/arm64/kvm/hyp/nvhe/Makefile +++ b/arch/arm64/kvm/hyp/nvhe/Makefile @@ -75,9 +75,9 @@ quiet_cmd_hyprel = HYPREL $@ quiet_cmd_hypcopy = HYPCOPY $@ cmd_hypcopy = $(OBJCOPY) --prefix-symbols=__kvm_nvhe_ $< $@ -# Remove ftrace and Shadow Call Stack CFLAGS. -# This is equivalent to the 'notrace' and '__noscs' annotations. -KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS), $(KBUILD_CFLAGS)) +# Remove ftrace, Shadow Call Stack, and CFI CFLAGS. +# This is equivalent to the 'notrace', '__noscs', and '__nocfi' annotations. +KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS) $(CC_FLAGS_CFI), $(KBUILD_CFLAGS)) # KVM nVHE code is run at a different exception code with a different map, so # compiler instrumentation that inserts callbacks or checks into the code may From patchwork Thu Apr 8 18:28:43 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 12192209 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-26.2 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 66C32C433ED for ; Thu, 8 Apr 2021 18:31:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 40314610FC for ; Thu, 8 Apr 2021 18:31:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232913AbhDHSbX (ORCPT ); Thu, 8 Apr 2021 14:31:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48708 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232981AbhDHSaz (ORCPT ); Thu, 8 Apr 2021 14:30:55 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 11D83C0610D2 for ; Thu, 8 Apr 2021 11:29:21 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id k15so2899605ybh.6 for ; Thu, 08 Apr 2021 11:29:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=wpJei33p36j3KjjMHxyiKmG4dj3y1cwd0hIxQebiEdM=; b=a3nRPCcLgUjC8+dAsZsjnXIQNP/rwy/DDjL0mVaRLZUSJLKjLCe23/7r3jufcOURP2 YfreigpdbzFmBPynu7ev4x2f9hGuOwXl1gQNFI+p2gMnNBATgfM6aNqo8eWkwib0f/8F EUNhOz40NxYK4iX4IsYefTQK+m8Ly9vO79flGB3PdZreeWclK/3HsvQa2Eu+zlw9dkH7 6qm5k1CF4uhU9Fd39Czmkl971aNRY+2JAKOGLjLe1yvMJopP7gW/T36sDYdpLNjW4pel /nYjwa7lv0PuEkaqdQpGCQ8z4533FqqU8pmp1ExKErObiCmjnfRuj5TuEngXRWPRbWkv GPuA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=wpJei33p36j3KjjMHxyiKmG4dj3y1cwd0hIxQebiEdM=; b=IiliH7Hvn5J8Pn5oJ4u/HTmQO+4Gf7O+Y4AlQWRUyhCKdDPlmKsH0zakzy+7uNfAH4 q2aHGheR2YiBvJq14zwaRgPIQtHPDcyDXAcm6HahBY7ih6F8dGTHv9QD6y2NBBzDbkOg hZ7oBsqwW+aGY4MafSOF7Y6wDPOzrtnlLgnkckxxaEk/bjz8KolJqecYH5GX/yxbEZvL VarCZpZ+DrMSL6OzJDqJnZX+Lio1Xq9BbzUoKqP0FiWCSRdfJA8ghSN1hs1ntwtm+pOL x8G6iejKrQqLtDCR+jBb0+qVll/7UJHFYknVXWH3cQtDe6o5xiM1OhAVPlB3xzFOZ7Ri bdhA== X-Gm-Message-State: AOAM533/83QaDbS8n/VVvGppx7EINs9MK2LPmWeCCyJJzydlFtIrYCTh zp/Ad/oZhT9E2zaBbHz0FvAK3T3CRaKzdU845p8= X-Google-Smtp-Source: ABdhPJy+nIguXtNRexvJIjrSyuROKE2OJGFq0G34E3vTRN1y9bOJbuovRIfl9/FQBpeHGk7p24GDKVlYncDOiGe0FU8= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:3560:8505:40a2:e021]) (user=samitolvanen job=sendgmr) by 2002:a25:cf16:: with SMTP id f22mr13542667ybg.342.1617906560306; Thu, 08 Apr 2021 11:29:20 -0700 (PDT) Date: Thu, 8 Apr 2021 11:28:43 -0700 In-Reply-To: <20210408182843.1754385-1-samitolvanen@google.com> Message-Id: <20210408182843.1754385-19-samitolvanen@google.com> Mime-Version: 1.0 References: <20210408182843.1754385-1-samitolvanen@google.com> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog Subject: [PATCH v6 18/18] arm64: allow CONFIG_CFI_CLANG to be selected From: Sami Tolvanen To: Kees Cook Cc: Nathan Chancellor , Nick Desaulniers , Masahiro Yamada , Will Deacon , Jessica Yu , Arnd Bergmann , Tejun Heo , "Paul E. McKenney" , Christoph Hellwig , Peter Zijlstra , Sedat Dilek , Mark Rutland , Catalin Marinas , bpf@vger.kernel.org, linux-hardening@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org Select ARCH_SUPPORTS_CFI_CLANG to allow CFI to be enabled. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Tested-by: Nathan Chancellor --- arch/arm64/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index e4e1b6550115..d7395772b6b8 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -75,6 +75,7 @@ config ARM64 select ARCH_SUPPORTS_SHADOW_CALL_STACK if CC_HAVE_SHADOW_CALL_STACK select ARCH_SUPPORTS_LTO_CLANG if CPU_LITTLE_ENDIAN select ARCH_SUPPORTS_LTO_CLANG_THIN + select ARCH_SUPPORTS_CFI_CLANG select ARCH_SUPPORTS_ATOMIC_RMW select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && (GCC_VERSION >= 50000 || CC_IS_CLANG) select ARCH_SUPPORTS_NUMA_BALANCING