From patchwork Wed Oct 30 07:31:07 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Russell Currey X-Patchwork-Id: 11219109 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8B50414DB for ; Wed, 30 Oct 2019 07:31:57 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id B389120874 for ; Wed, 30 Oct 2019 07:31:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=russell.cc header.i=@russell.cc header.b="T2jCpgQt"; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="axxoW2mW" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B389120874 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=russell.cc Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-17159-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 30458 invoked by uid 550); 30 Oct 2019 07:31:50 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 30285 invoked from network); 30 Oct 2019 07:31:48 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=russell.cc; h= from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; s=fm3; bh=aWW/U1viip+Ra EVEVqbP3tlb6Le1bU34dYIUMpujOsA=; b=T2jCpgQtcVhDZn+DY7h3r1LL4FVJx cYt/JY2xTSKhQM537Yghy6QacImI4zf9NFMQMhV0BHcfzm//Lt8Gk28K54/WNEyB 3KkV8pjonj5SgpxmAPgMHdNff58PWXo2qNB1/g/IOUqI0PWynMKnsQk1TAc0Ak+C R/mj11+k7ioDfQLRjGqxhBLMo2ENst7jqn0/OmB5Yar4+cACgRNKPYhv1xA4FOFR TDRwc3EZ4r2bBWRr48vIIcQIgyI1w+O1mHOKQz9VsAXs6Eoigzy4lZqCR7ch/968 dUKokgzR26Xqcdy2V7njvqw1UYhOmRnJ2fyFZocBpEbDpu2Ts7pcW9jTg== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:date:from :in-reply-to:message-id:mime-version:references:subject:to :x-me-proxy:x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s= fm1; bh=aWW/U1viip+RaEVEVqbP3tlb6Le1bU34dYIUMpujOsA=; b=axxoW2mW 3KF3I4v7sCt/BoDJfQypCMQ+7NpfP9l6AYCY/bxLsR3h3b9duVrosnOpnw/0a7aL 88ImpHrkBFgvUwqVx5DB5k6nr3f5gkfoYARQOSECjxjdpou2/9fiGiGoGw76wp14 pWvB2ua4mRw9yrmTtAl6L/BzmmHJqJyOHBemH0r2/6qQI4luQyWU+mesqTTiPiIk kEcAf6HUDfKrfssRsBxGCSCnjhzCWQTPz50kbkFDDSajEFJudxTlLeq3ChQJRg95 yf6RGJxvObYdwH64v6faZ+xb/yVULCZfsBDXjo2TaEo9b7VEeDwdg+EqCDroEm8l 327MutKjRaIEvA== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedufedruddtvddguddtlecutefuodetggdotefrod ftvfcurfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfgh necuuegrihhlohhuthemuceftddtnecufghrlhcuvffnffculdeftddmnecujfgurhephf fvufffkffojghfggfgsedtkeertdertddtnecuhfhrohhmpeftuhhsshgvlhhlucevuhhr rhgvhicuoehruhhstghurhesrhhushhsvghllhdrtggtqeenucfkphepuddvvddrleelrd ekvddruddtnecurfgrrhgrmhepmhgrihhlfhhrohhmpehruhhstghurhesrhhushhsvghl lhdrtggtnecuvehluhhsthgvrhfuihiivgeptd X-ME-Proxy: From: Russell Currey To: linuxppc-dev@lists.ozlabs.org Cc: Russell Currey , christophe.leroy@c-s.fr, joel@jms.id.au, mpe@ellerman.id.au, ajd@linux.ibm.com, dja@axtens.net, npiggin@gmail.com, kernel-hardening@lists.openwall.com Subject: [PATCH v5 1/5] powerpc/mm: Implement set_memory() routines Date: Wed, 30 Oct 2019 18:31:07 +1100 Message-Id: <20191030073111.140493-2-ruscur@russell.cc> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191030073111.140493-1-ruscur@russell.cc> References: <20191030073111.140493-1-ruscur@russell.cc> MIME-Version: 1.0 The set_memory_{ro/rw/nx/x}() functions are required for STRICT_MODULE_RWX, and are generally useful primitives to have. This implementation is designed to be completely generic across powerpc's many MMUs. It's possible that this could be optimised to be faster for specific MMUs, but the focus is on having a generic and safe implementation for now. This implementation does not handle cases where the caller is attempting to change the mapping of the page it is executing from, or if another CPU is concurrently using the page being altered. These cases likely shouldn't happen, but a more complex implementation with MMU-specific code could safely handle them, so that is left as a TODO for now. Signed-off-by: Russell Currey --- arch/powerpc/Kconfig | 1 + arch/powerpc/include/asm/set_memory.h | 32 +++++++++++ arch/powerpc/mm/Makefile | 1 + arch/powerpc/mm/pageattr.c | 77 +++++++++++++++++++++++++++ 4 files changed, 111 insertions(+) create mode 100644 arch/powerpc/include/asm/set_memory.h create mode 100644 arch/powerpc/mm/pageattr.c diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 3e56c9c2f16e..8f7005f0d097 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -133,6 +133,7 @@ config PPC select ARCH_HAS_PTE_SPECIAL select ARCH_HAS_MEMBARRIER_CALLBACKS select ARCH_HAS_SCALED_CPUTIME if VIRT_CPU_ACCOUNTING_NATIVE && PPC_BOOK3S_64 + select ARCH_HAS_SET_MEMORY select ARCH_HAS_STRICT_KERNEL_RWX if ((PPC_BOOK3S_64 || PPC32) && !RELOCATABLE && !HIBERNATION) select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST select ARCH_HAS_UACCESS_FLUSHCACHE diff --git a/arch/powerpc/include/asm/set_memory.h b/arch/powerpc/include/asm/set_memory.h new file mode 100644 index 000000000000..5230ddb2fefd --- /dev/null +++ b/arch/powerpc/include/asm/set_memory.h @@ -0,0 +1,32 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_POWERPC_SET_MEMORY_H +#define _ASM_POWERPC_SET_MEMORY_H + +#define SET_MEMORY_RO 1 +#define SET_MEMORY_RW 2 +#define SET_MEMORY_NX 3 +#define SET_MEMORY_X 4 + +int change_memory_attr(unsigned long addr, int numpages, int action); + +static inline int set_memory_ro(unsigned long addr, int numpages) +{ + return change_memory_attr(addr, numpages, SET_MEMORY_RO); +} + +static inline int set_memory_rw(unsigned long addr, int numpages) +{ + return change_memory_attr(addr, numpages, SET_MEMORY_RW); +} + +static inline int set_memory_nx(unsigned long addr, int numpages) +{ + return change_memory_attr(addr, numpages, SET_MEMORY_NX); +} + +static inline int set_memory_x(unsigned long addr, int numpages) +{ + return change_memory_attr(addr, numpages, SET_MEMORY_X); +} + +#endif diff --git a/arch/powerpc/mm/Makefile b/arch/powerpc/mm/Makefile index 5e147986400d..d0a0bcbc9289 100644 --- a/arch/powerpc/mm/Makefile +++ b/arch/powerpc/mm/Makefile @@ -20,3 +20,4 @@ obj-$(CONFIG_HIGHMEM) += highmem.o obj-$(CONFIG_PPC_COPRO_BASE) += copro_fault.o obj-$(CONFIG_PPC_PTDUMP) += ptdump/ obj-$(CONFIG_KASAN) += kasan/ +obj-$(CONFIG_ARCH_HAS_SET_MEMORY) += pageattr.o diff --git a/arch/powerpc/mm/pageattr.c b/arch/powerpc/mm/pageattr.c new file mode 100644 index 000000000000..aedd79173a44 --- /dev/null +++ b/arch/powerpc/mm/pageattr.c @@ -0,0 +1,77 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * MMU-generic set_memory implementation for powerpc + * + * Copyright 2019, IBM Corporation. + */ + +#include +#include + +#include +#include +#include + + +/* + * Updates the attributes of a page in three steps: + * + * 1. invalidate the page table entry + * 2. flush the TLB + * 3. install the new entry with the updated attributes + * + * This is unsafe if the caller is attempting to change the mapping of the + * page it is executing from, or if another CPU is concurrently using the + * page being altered. + * + * TODO make the implementation resistant to this. + */ +static int change_page_attr(pte_t *ptep, unsigned long addr, void *data) +{ + int action = *((int *)data); + pte_t pte_val; + int ret = 0; + + spin_lock(&init_mm.page_table_lock); + + // invalidate the PTE so it's safe to modify + pte_val = ptep_get_and_clear(&init_mm, addr, ptep); + flush_tlb_kernel_range(addr, addr + PAGE_SIZE); + + // modify the PTE bits as desired, then apply + switch (action) { + case SET_MEMORY_RO: + pte_val = pte_wrprotect(pte_val); + break; + case SET_MEMORY_RW: + pte_val = pte_mkwrite(pte_val); + break; + case SET_MEMORY_NX: + pte_val = pte_exprotect(pte_val); + break; + case SET_MEMORY_X: + pte_val = pte_mkexec(pte_val); + break; + default: + WARN_ON(true); + ret = -EINVAL; + goto out; + } + + set_pte_at(&init_mm, addr, ptep, pte_val); +out: + spin_unlock(&init_mm.page_table_lock); + return ret; +} + +int change_memory_attr(unsigned long addr, int numpages, int action) +{ + unsigned long start = ALIGN_DOWN(addr, PAGE_SIZE); + unsigned long size = numpages * PAGE_SIZE; + + if (!numpages) + return 0; + + return apply_to_page_range(&init_mm, start, size, change_page_attr, &action); +} From patchwork Wed Oct 30 07:31:08 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Russell Currey X-Patchwork-Id: 11219111 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 94C1614DB for ; Wed, 30 Oct 2019 07:32:05 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id E9E6C2054F for ; Wed, 30 Oct 2019 07:32:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=russell.cc header.i=@russell.cc header.b="fUbva0VU"; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="ddwjSpVs" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E9E6C2054F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=russell.cc Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-17160-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 31802 invoked by uid 550); 30 Oct 2019 07:31:53 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 30677 invoked from network); 30 Oct 2019 07:31:52 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=russell.cc; h= from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; s=fm3; bh=PStFRxzl4Zn7i 9v7bh9ypxBUch/1PPtigM566gooksQ=; b=fUbva0VUoW4csLSpYm3mhaiivuyMW 8sRt1lYCXXnTTZXLkB5LnsRQpohIp+jOLZ7G8E/khms2c6mDCQciP53vZ5ECyykB XAXuhSKE/wGmk6vovf5uWpg+w0YvGFPQUhAuTkhJaGZULmeIqvOUtlhw2nzsSfi1 mZ4IctumSoCBczPZPGmFWV8MtVHfkrK8cTInKsJiv0HjX5tiywY4WPaHJFevt6le ew40J9cOoLOJ0z2e49gUlW6lzmk3xY36cgNEQAvTscu5GUeGNkTNOpwCo76vzF52 ZlA+hgxRPIh7xYHAZQOp7OLJJI0iUN7od84406T22WCgBzcno/xt35Q8w== DKIM-Signature: v=1; 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This can be tested with CONFIG_PPC_PTDUMP=y and CONFIG_PPC_DEBUG_WX=y set, and checking the kernel log during boot. powerpc doesn't implement its own alloc() for kprobes like other architectures do, but we couldn't immediately mark RO anyway since we do a memcpy to the page we allocate later. After that, nothing should be allowed to modify the page, and write permissions are removed well before the kprobe is armed. Thus mark newly allocated probes as read-only once it's safe to do so. Signed-off-by: Russell Currey Reviewed-by: Daniel Axtens --- arch/powerpc/kernel/kprobes.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c index 2d27ec4feee4..2610496de7c7 100644 --- a/arch/powerpc/kernel/kprobes.c +++ b/arch/powerpc/kernel/kprobes.c @@ -24,6 +24,7 @@ #include #include #include +#include DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL; DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk); @@ -131,6 +132,8 @@ int arch_prepare_kprobe(struct kprobe *p) (unsigned long)p->ainsn.insn + sizeof(kprobe_opcode_t)); } + set_memory_ro((unsigned long)p->ainsn.insn, 1); + p->ainsn.boostable = 0; return ret; } From patchwork Wed Oct 30 07:31:09 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Russell Currey X-Patchwork-Id: 11219113 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3A7521515 for ; Wed, 30 Oct 2019 07:32:14 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 906302054F for ; Wed, 30 Oct 2019 07:32:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=russell.cc header.i=@russell.cc header.b="lFArQLig"; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="RTfGwNn4" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 906302054F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=russell.cc Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-17161-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 32110 invoked by uid 550); 30 Oct 2019 07:31:56 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 32014 invoked from network); 30 Oct 2019 07:31:55 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=russell.cc; h= from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; s=fm3; bh=HYGtzzTlMcF3v eMN2AqVXMM15POrvmVyLU/o7hZnrc4=; b=lFArQLiguLC0Fok+qmwTKyvb8dtBh YEBgz8LH9y+dcyzK9DqkUO6BHsjByz7Z6eSJ7OgMM4I7SHTzm62TtE2GH+ChYtkU 5SH+3bRkGyAd7gmxX89yCHt32YI1Eu7WfziVndA6ZW1L7bGJ4JYCRL+zffNHpSvG EHVUAaZdCkRHfKJKBgeRZ0cNqGYXTaF1QmYBGGQfgPN4/DspLpD4xGPURGZKEYBn Z4ErZGBnDJKWvH4sQ986SFbzdlzP6GR8Q+IgwTd/k+9vR3Su5tQFDwyP3e2V++p2 lYsUan2GN7uSSpXTId//fAiS5iX7jGGX9dP+y9duKAQwj62yDFhTvvnmQ== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:date:from :in-reply-to:message-id:mime-version:references:subject:to :x-me-proxy:x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s= fm1; bh=HYGtzzTlMcF3veMN2AqVXMM15POrvmVyLU/o7hZnrc4=; b=RTfGwNn4 wj5qK3LdUONToXnvLOfnyujjyf8ksolxUKufUowgxmeEQXWHxqGMyEyGmAhISDy1 LMtDZFiudOqrip+J8Evbx/DzuSK0pvz5EyBTCXq0U7/BBJNfQNKP1c6fCfyiSo5/ 1eqSvDjr7xBjlBeGHBppy6MX3p3IHyMCwBe+C49XMX9oeiMHyRWbakVjPY5axCkc yyIcWVbBP1QBSc8slJKfrjJpWT2m9uhOWuEw9Cd5RpZZbSNT7gJfRk+ypdyLoC4A Ub9ar+i07UGiGUF907ZU8uroeXnure1qP6Uk+GTIrsBbN5ij/C5jj0jeMxf4bWZl QaCBpNNZsibQ2g== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedufedruddtvddguddtlecutefuodetggdotefrod ftvfcurfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfgh necuuegrihhlohhuthemuceftddtnecufghrlhcuvffnffculdeftddmnecujfgurhephf fvufffkffojghfggfgsedtkeertdertddtnecuhfhrohhmpeftuhhsshgvlhhlucevuhhr rhgvhicuoehruhhstghurhesrhhushhsvghllhdrtggtqeenucfkphepuddvvddrleelrd ekvddruddtnecurfgrrhgrmhepmhgrihhlfhhrohhmpehruhhstghurhesrhhushhsvghl lhdrtggtnecuvehluhhsthgvrhfuihiivgepud X-ME-Proxy: From: Russell Currey To: linuxppc-dev@lists.ozlabs.org Cc: Russell Currey , christophe.leroy@c-s.fr, joel@jms.id.au, mpe@ellerman.id.au, ajd@linux.ibm.com, dja@axtens.net, npiggin@gmail.com, kernel-hardening@lists.openwall.com Subject: [PATCH v5 3/5] powerpc/mm/ptdump: debugfs handler for W+X checks at runtime Date: Wed, 30 Oct 2019 18:31:09 +1100 Message-Id: <20191030073111.140493-4-ruscur@russell.cc> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191030073111.140493-1-ruscur@russell.cc> References: <20191030073111.140493-1-ruscur@russell.cc> MIME-Version: 1.0 Very rudimentary, just echo 1 > [debugfs]/check_wx_pages and check the kernel log. Useful for testing strict module RWX. Updated the Kconfig entry to reflect this. Also fixed a typo. Signed-off-by: Russell Currey --- arch/powerpc/Kconfig.debug | 6 ++++-- arch/powerpc/mm/ptdump/ptdump.c | 21 ++++++++++++++++++++- 2 files changed, 24 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/Kconfig.debug b/arch/powerpc/Kconfig.debug index c59920920ddc..dcfe83d4c211 100644 --- a/arch/powerpc/Kconfig.debug +++ b/arch/powerpc/Kconfig.debug @@ -370,7 +370,7 @@ config PPC_PTDUMP If you are unsure, say N. config PPC_DEBUG_WX - bool "Warn on W+X mappings at boot" + bool "Warn on W+X mappings at boot & enable manual checks at runtime" depends on PPC_PTDUMP help Generate a warning if any W+X mappings are found at boot. @@ -384,7 +384,9 @@ config PPC_DEBUG_WX of other unfixed kernel bugs easier. There is no runtime or memory usage effect of this option - once the kernel has booted up - it's a one time check. + once the kernel has booted up, it only automatically checks once. + + Enables the "check_wx_pages" debugfs entry for checking at runtime. If in doubt, say "Y". diff --git a/arch/powerpc/mm/ptdump/ptdump.c b/arch/powerpc/mm/ptdump/ptdump.c index 2f9ddc29c535..b6cba29ae4a0 100644 --- a/arch/powerpc/mm/ptdump/ptdump.c +++ b/arch/powerpc/mm/ptdump/ptdump.c @@ -4,7 +4,7 @@ * * This traverses the kernel pagetables and dumps the * information about the used sections of memory to - * /sys/kernel/debug/kernel_pagetables. + * /sys/kernel/debug/kernel_page_tables. * * Derived from the arm64 implementation: * Copyright (c) 2014, The Linux Foundation, Laura Abbott. @@ -409,6 +409,25 @@ void ptdump_check_wx(void) else pr_info("Checked W+X mappings: passed, no W+X pages found\n"); } + +static int check_wx_debugfs_set(void *data, u64 val) +{ + if (val != 1ULL) + return -EINVAL; + + ptdump_check_wx(); + + return 0; +} + +DEFINE_SIMPLE_ATTRIBUTE(check_wx_fops, NULL, check_wx_debugfs_set, "%llu\n"); + +static int ptdump_check_wx_init(void) +{ + return debugfs_create_file("check_wx_pages", 0200, NULL, + NULL, &check_wx_fops) ? 0 : -ENOMEM; +} +device_initcall(ptdump_check_wx_init); #endif static int ptdump_init(void) From patchwork Wed Oct 30 07:31:10 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Russell Currey X-Patchwork-Id: 11219115 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4C0421515 for ; Wed, 30 Oct 2019 07:32:23 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 9EF5D2054F for ; Wed, 30 Oct 2019 07:32:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=russell.cc header.i=@russell.cc header.b="wQqtnQ5H"; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="TFH+9GaA" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9EF5D2054F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=russell.cc Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-17162-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 32469 invoked by uid 550); 30 Oct 2019 07:31:59 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 32358 invoked from network); 30 Oct 2019 07:31:58 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=russell.cc; h= from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; s=fm3; bh=WVehznCtMHUGH kkWKbgrT+yshqhj8IDof9KJa08Bq0M=; b=wQqtnQ5HYN2HhoT1Mr87LlzHxpDs7 OMsTrzNUySexfr30//65eaX8cpiOXynT2XstIB7xpO9nDKCYhGmr4Dn20QbNrHwF bwOeY3brgkuk0LMOPVHmDWy+vw29Z/QqEqkIjhmEBHwKIj5kq+5emLcws1Sg+MQV m9b3AUY1SmWZRDPrkmHZJ6l/nXucf7c1riUjOFGSrxmjpiSNnjFpoIVgJ+hQvInW ks8h83RzQXMYM6bADNP5kWgntJHeVY7bjuT9Z5+ueZ7fLps/pxd6p2YXdN7DgDVn Ceh2utf81BEp/+TdoDIxWLBVq3lidTFgcW9ckA8zQYLrU4juPD+yJ8aQg== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:date:from :in-reply-to:message-id:mime-version:references:subject:to :x-me-proxy:x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s= fm1; bh=WVehznCtMHUGHkkWKbgrT+yshqhj8IDof9KJa08Bq0M=; b=TFH+9GaA 0fjJovwpMWyMGSwcxoYcAkWolg1X1ViCME68QalsBhlA61Ln4C+ViZqrWDY/ojw/ sM+Zt5IGQorEFngxAzVETzbMT976Uq4MKfJAqQ48M6WpEnv0VwHtnAVi55X1tmOA 4mbmbUnHefBbu+akPM5BmrleJKw6sW8r3SgBpToCpBMnmxa/0CYz9JDPi1Rko5Q+ RJCRgpcnpON1FsCp/Akomz+oA/Uf80LfdAFHRiiFaTEKbn8ENhQt+FC6Qdb3SbvU nQ6SmqtKNxS+vrV0pbs0LM/iXekAMHrABRayVvntgy1rlMF0CAcUIAGYvIPvNDTy nLlHbbkcj0CT9A== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedufedruddtvddguddtlecutefuodetggdotefrod ftvfcurfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfgh necuuegrihhlohhuthemuceftddtnecufghrlhcuvffnffculdeftddmnecujfgurhephf fvufffkffojghfggfgsedtkeertdertddtnecuhfhrohhmpeftuhhsshgvlhhlucevuhhr rhgvhicuoehruhhstghurhesrhhushhsvghllhdrtggtqeenucfkphepuddvvddrleelrd ekvddruddtnecurfgrrhgrmhepmhgrihhlfhhrohhmpehruhhstghurhesrhhushhsvghl lhdrtggtnecuvehluhhsthgvrhfuihiivgepfe X-ME-Proxy: From: Russell Currey To: linuxppc-dev@lists.ozlabs.org Cc: Russell Currey , christophe.leroy@c-s.fr, joel@jms.id.au, mpe@ellerman.id.au, ajd@linux.ibm.com, dja@axtens.net, npiggin@gmail.com, kernel-hardening@lists.openwall.com Subject: [PATCH v5 4/5] powerpc: Set ARCH_HAS_STRICT_MODULE_RWX Date: Wed, 30 Oct 2019 18:31:10 +1100 Message-Id: <20191030073111.140493-5-ruscur@russell.cc> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191030073111.140493-1-ruscur@russell.cc> References: <20191030073111.140493-1-ruscur@russell.cc> MIME-Version: 1.0 To enable strict module RWX on powerpc, set: CONFIG_STRICT_MODULE_RWX=y You should also have CONFIG_STRICT_KERNEL_RWX=y set to have any real security benefit. ARCH_HAS_STRICT_MODULE_RWX is set to require ARCH_HAS_STRICT_KERNEL_RWX. This is due to a quirk in arch/Kconfig and arch/powerpc/Kconfig that makes STRICT_MODULE_RWX *on by default* in configurations where STRICT_KERNEL_RWX is *unavailable*. Since this doesn't make much sense, and module RWX without kernel RWX doesn't make much sense, having the same dependencies as kernel RWX works around this problem. Signed-off-by: Russell Currey --- This means that Daniel's test on book3e64 is pretty useless since we've gone from being unable to turn it *off* to being unable to turn it *on*. I think this is the right course of action for now. arch/powerpc/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 8f7005f0d097..52028e27f2d3 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -135,6 +135,7 @@ config PPC select ARCH_HAS_SCALED_CPUTIME if VIRT_CPU_ACCOUNTING_NATIVE && PPC_BOOK3S_64 select ARCH_HAS_SET_MEMORY select ARCH_HAS_STRICT_KERNEL_RWX if ((PPC_BOOK3S_64 || PPC32) && !RELOCATABLE && !HIBERNATION) + select ARCH_HAS_STRICT_MODULE_RWX if ARCH_HAS_STRICT_KERNEL_RWX select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST select ARCH_HAS_UACCESS_FLUSHCACHE select ARCH_HAS_UACCESS_MCSAFE if PPC64 From patchwork Wed Oct 30 07:31:11 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Russell Currey X-Patchwork-Id: 11219117 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3FA5114DB for ; Wed, 30 Oct 2019 07:32:33 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 939F12054F for ; Wed, 30 Oct 2019 07:32:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=russell.cc header.i=@russell.cc header.b="Tww42pkW"; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="gG69+En0" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 939F12054F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=russell.cc Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-17163-patchwork-kernel-hardening=patchwork.kernel.org@lists.openwall.com Received: (qmail 32763 invoked by uid 550); 30 Oct 2019 07:32:02 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 32680 invoked from network); 30 Oct 2019 07:32:02 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=russell.cc; h= from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; s=fm3; bh=dc5AVIQHNoFf/ A7cIAbY87X8bxKg7zfElk6aDCs1HSg=; b=Tww42pkWm30LkhW5jHkFBwOEvZBDD b81996v6Bs0M+S2po+hTsjVJitX0ylEzGJ2ApHFfvdOQsiEx+WwL0LFschtGoiff 3rGhnffxxUnYw0GkopYB6Yd35uOBV0UstdZ79BVlLvC1RpgFp+uPJQYuC2dstFb5 n41XF4IAfOMDUpC/+iva6Pl2B5CEPVNzUcxlcpBPDpC9BGb6jtPHdk3ZgGBDMHJ9 uqeu20jo5U+gg9rWDaJ0LvOOuRauc3TgHBQiNONOylC/kQ30Qu2qeJP5Oh5Nw3dD aCK0ZZARRuwAiXVIGn81e8Yj0X4+hUR31k1cObD9kMsElfFkUGJQuFrEA== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:date:from :in-reply-to:message-id:mime-version:references:subject:to :x-me-proxy:x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s= fm1; bh=dc5AVIQHNoFf/A7cIAbY87X8bxKg7zfElk6aDCs1HSg=; b=gG69+En0 okZ1PKBi1VWrL7NU7JrkDF7mBCANG6r3qsetj5yGE7UpamgxGLs5WbPJgagnTU9f fjbwdLrlZulK1woLQYcbTtptIxwTn9WDYWhN+Q/62DWoLxiLWBWJVXmMMWFj1Pc0 xPIFePoimmNMzB6nd+0PrQi986DmG9Vpbyh7kE1/qPEebN12+CJTU6zmgX0oyiNw XbL+sOfZ/NqLSb1z1RXZ9rMyx7DRSYpgSJc5rGnkyTtxQ7EdkBA4fLG2SCljuUAK T1oW5X7/dicWAAm1mJfwtiUjES/2Ik8rwqSUzjzTkJW0zVWTas/YAQpLi47BnHil k3iXpM8mXSuvOg== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedufedruddtvddguddtlecutefuodetggdotefrod ftvfcurfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfgh necuuegrihhlohhuthemuceftddtnecufghrlhcuvffnffculdeftddmnecujfgurhephf fvufffkffojghfggfgsedtkeertdertddtnecuhfhrohhmpeftuhhsshgvlhhlucevuhhr rhgvhicuoehruhhstghurhesrhhushhsvghllhdrtggtqeenucfkphepuddvvddrleelrd ekvddruddtnecurfgrrhgrmhepmhgrihhlfhhrohhmpehruhhstghurhesrhhushhsvghl lhdrtggtnecuvehluhhsthgvrhfuihiivgepfe X-ME-Proxy: From: Russell Currey To: linuxppc-dev@lists.ozlabs.org Cc: Russell Currey , christophe.leroy@c-s.fr, joel@jms.id.au, mpe@ellerman.id.au, ajd@linux.ibm.com, dja@axtens.net, npiggin@gmail.com, kernel-hardening@lists.openwall.com Subject: [PATCH v5 5/5] powerpc/configs: Enable STRICT_MODULE_RWX in skiroot_defconfig Date: Wed, 30 Oct 2019 18:31:11 +1100 Message-Id: <20191030073111.140493-6-ruscur@russell.cc> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191030073111.140493-1-ruscur@russell.cc> References: <20191030073111.140493-1-ruscur@russell.cc> MIME-Version: 1.0 skiroot_defconfig is the only powerpc defconfig with STRICT_KERNEL_RWX enabled, and if you want memory protection for kernel text you'd want it for modules too, so enable STRICT_MODULE_RWX there. Signed-off-by: Russell Currey Acked-by: Joel Stanley --- arch/powerpc/configs/skiroot_defconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/powerpc/configs/skiroot_defconfig b/arch/powerpc/configs/skiroot_defconfig index 1253482a67c0..719d899081b3 100644 --- a/arch/powerpc/configs/skiroot_defconfig +++ b/arch/powerpc/configs/skiroot_defconfig @@ -31,6 +31,7 @@ CONFIG_PERF_EVENTS=y CONFIG_SLAB_FREELIST_HARDENED=y CONFIG_JUMP_LABEL=y CONFIG_STRICT_KERNEL_RWX=y +CONFIG_STRICT_MODULE_RWX=y CONFIG_MODULES=y CONFIG_MODULE_UNLOAD=y CONFIG_MODULE_SIG=y