From patchwork Mon Oct 23 13:20:40 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 13432850 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 230AFCDB474 for ; Mon, 23 Oct 2023 13:25:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231282AbjJWNZx (ORCPT ); Mon, 23 Oct 2023 09:25:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52168 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233529AbjJWNZS (ORCPT ); Mon, 23 Oct 2023 09:25:18 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3D5822723; Mon, 23 Oct 2023 06:23:33 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id F0C2AC433CB; Mon, 23 Oct 2023 13:23:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1698067412; bh=Aen7tI3tV8QliCw4GY+TVMrWQ7BjK/IzHu4XGOJDu+I=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=PUfhQYxG5F0WWBAvnGb5yUqpTjKpqij1bAq1dz2aGNEJTdM21ed2h+AqiTYM4ZCBp MtlbaqQgbdsQeLgLuQq1kjoALRDhtqoH5zI7zBHjKemt1ZfrhbSGovRJHa7G5yZMK/ P/s9t+UrumP48n9xlevqPHF8V57ikEOzwivvMfmxhE3HDTyTR4z/qJ9cNEApJvKf97 bshm3781uRRExdCR1Id9g2S7sFCxd1RGq679qLe/Egl37bSl6n3tubjvKoaUetIXay BaVYxt+MSMf6Hrh/HcfYZ2zf6Q6JckNeQxc1Kp1jr1WXu/DB13x+Nd32qYtFXXypvw jnFevocx0bv2w== From: Mark Brown Date: Mon, 23 Oct 2023 14:20:40 +0100 Subject: [PATCH RFC RFT 1/5] mm: Introduce ARCH_HAS_USER_SHADOW_STACK MIME-Version: 1.0 Message-Id: <20231023-clone3-shadow-stack-v1-1-d867d0b5d4d0@kernel.org> References: <20231023-clone3-shadow-stack-v1-0-d867d0b5d4d0@kernel.org> In-Reply-To: <20231023-clone3-shadow-stack-v1-0-d867d0b5d4d0@kernel.org> To: "Rick P. Edgecombe" , Deepak Gupta , Szabolcs Nagy , "H.J. Lu" , Florian Weimer , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Daniel Bristot de Oliveira , Valentin Schneider , Christian Brauner , Shuah Khan Cc: linux-kernel@vger.kernel.org, Catalin Marinas , Will Deacon , linux-kselftest@vger.kernel.org, linux-api@vger.kernel.org, Mark Brown , David Hildenbrand X-Mailer: b4 0.13-dev-0438c X-Developer-Signature: v=1; a=openpgp-sha256; l=2302; i=broonie@kernel.org; h=from:subject:message-id; bh=Aen7tI3tV8QliCw4GY+TVMrWQ7BjK/IzHu4XGOJDu+I=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBlNnPDFVIE5B+3ze9Js5B/BaPIgTybaZYHGdRh4PW0 6Oj2umeJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCZTZzwwAKCRAk1otyXVSH0KE8B/ 0Yhwcn5e0MrNb78oefgVk9aNyTT/WKEGRnXSgKXCdjkNFZhT2+xTmF9ITt1dweV+G4orXP7/lL+SOT FJvK8bgzC6IS4CdUypaNnYJYDL9hlfmWcFWgtiPmZnXOy1dLwT43nEuOhMBqgKgP8nw2AJMlvujjN7 DHc/b3+j/+lpbkBqsT79SEqUUS0K1eUhDlGBnyNLTJaxgwFd+M9U0WNoGjYqydgXpI68STiW6dFrUa pKEsaxwMtgm9IUGReNwDpcsR0jrQlNIlRElT07IC2RVlr3JPw4G8QRdWPtgV+h9dmQYSjVvfQxAh9k u0YSVwQb/NmgC9/VB0M6Cysl/4Hp+p X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Since multiple architectures have support for shadow stacks and we need to select support for this feature in several places in the generic code provide a generic config option that the architectures can select. Suggested-by: David Hildenbrand Signed-off-by: Mark Brown --- arch/x86/Kconfig | 1 + fs/proc/task_mmu.c | 2 +- include/linux/mm.h | 2 +- mm/Kconfig | 6 ++++++ 4 files changed, 9 insertions(+), 2 deletions(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 66bfabae8814..2b72bae0d877 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1926,6 +1926,7 @@ config X86_USER_SHADOW_STACK depends on AS_WRUSS depends on X86_64 select ARCH_USES_HIGH_VMA_FLAGS + select ARCH_HAS_USER_SHADOW_STACK select X86_CET help Shadow stack protection is a hardware feature that detects function diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 3dd5be96691b..4101e741663a 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -697,7 +697,7 @@ static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma) #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_MINOR [ilog2(VM_UFFD_MINOR)] = "ui", #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */ -#ifdef CONFIG_X86_USER_SHADOW_STACK +#ifdef CONFIG_ARCH_HAS_USER_SHADOW_STACK [ilog2(VM_SHADOW_STACK)] = "ss", #endif }; diff --git a/include/linux/mm.h b/include/linux/mm.h index bf5d0b1b16f4..1728cb77540d 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -341,7 +341,7 @@ extern unsigned int kobjsize(const void *objp); #endif #endif /* CONFIG_ARCH_HAS_PKEYS */ -#ifdef CONFIG_X86_USER_SHADOW_STACK +#ifdef CONFIG_ARCH_HAS_USER_SHADOW_STACK /* * VM_SHADOW_STACK should not be set with VM_SHARED because of lack of * support core mm. diff --git a/mm/Kconfig b/mm/Kconfig index 264a2df5ecf5..aaa2c353ea67 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -1258,6 +1258,12 @@ config LOCK_MM_AND_FIND_VMA bool depends on !STACK_GROWSUP +config ARCH_HAS_USER_SHADOW_STACK + bool + help + The architecture has hardware support for userspace shadow call + stacks (eg, x86 CET, arm64 GCS, RISC-V Zisslpcfi). + source "mm/damon/Kconfig" endmenu From patchwork Mon Oct 23 13:20:41 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 13432851 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 26333C004C0 for ; Mon, 23 Oct 2023 13:26:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231407AbjJWNZ7 (ORCPT ); Mon, 23 Oct 2023 09:25:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52110 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233381AbjJWNZV (ORCPT ); Mon, 23 Oct 2023 09:25:21 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4D676273A; Mon, 23 Oct 2023 06:23:39 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4492FC433C8; Mon, 23 Oct 2023 13:23:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1698067418; bh=wUhiPV1iw/5mTPqUKRQaD3BHKH1V6EDBJD2oIZClkvc=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=nGcN4xaZJOZpByeL3Ayx5QzDfmypqpMnK8lokOLB7QruiZ3thaLZaWhQ0T99Y0euE Qr4AqWp7GOf7AvZLpGO/FbTrVQtKMm0PQoiTjMvcEzohcUB1jqfSlxzRWDrvPBzWSp 0cdDkziHj4QyL03v9P7ojQ14LvAHmHhwsKWJYkPAABkH6drppV6HF3c+FvG7ZKhxi3 OVF2bVyE/Z88TXyDO6XSYVaYF0vOg4s4HBt9Dn+nEbcONxeuUnAAROK0XUIs/2ase8 wBkJocc/4oFhBLDyKOn57gZ7J5E5hC0KxMO3gAMW0/Cel8WXhexOh428rGnFXdEA+Z DuXfOzm6Wnylw== From: Mark Brown Date: Mon, 23 Oct 2023 14:20:41 +0100 Subject: [PATCH RFC RFT 2/5] fork: Add shadow stack support to clone3() MIME-Version: 1.0 Message-Id: <20231023-clone3-shadow-stack-v1-2-d867d0b5d4d0@kernel.org> References: <20231023-clone3-shadow-stack-v1-0-d867d0b5d4d0@kernel.org> In-Reply-To: <20231023-clone3-shadow-stack-v1-0-d867d0b5d4d0@kernel.org> To: "Rick P. Edgecombe" , Deepak Gupta , Szabolcs Nagy , "H.J. Lu" , Florian Weimer , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Daniel Bristot de Oliveira , Valentin Schneider , Christian Brauner , Shuah Khan Cc: linux-kernel@vger.kernel.org, Catalin Marinas , Will Deacon , linux-kselftest@vger.kernel.org, linux-api@vger.kernel.org, Mark Brown X-Mailer: b4 0.13-dev-0438c X-Developer-Signature: v=1; a=openpgp-sha256; l=10498; i=broonie@kernel.org; h=from:subject:message-id; bh=wUhiPV1iw/5mTPqUKRQaD3BHKH1V6EDBJD2oIZClkvc=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBlNnPETIgl8yM0h7STe4LPhtBTXAUmlBEabHthxCru eKqExeuJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCZTZzxAAKCRAk1otyXVSH0GmgB/ 9l1Ceu7k2k8Hhe2yBQXNjM5f2ApqPb5FUWmdlWwfmIebt0Q6VuYITF3Y+OsPjaJwh+2FYa0oseE86e vm5E1HsH/or6m3tfMZ8+rbrgMWQ7j+eLDh2+v0iF4fpNK9QCCw01y+jrr07juifty90wOr80tHeG7y D6Y2+OCdEUBNqzHoQOVlpKlmK8y/zUGwIDQ0BcE5Km+Wp6BJ3kalAxNemTSmJX0GGUaqk/EgQQZq/U isWfNNqeUNJtpFNIdt6vu4TVEeNN1yAl1HDLPO9XGw5aP0BVGmgBmJ6eS7SSvGp+LCVjd4Co+dkpGl rlOnKw9IclRfIkQbBggSxdttOE41IR X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Unlike with the normal stack there is no API for configuring the the shadow stack for a new thread, instead the kernel will dynamically allocate a new shadow stack with the same size as the normal stack. This appears to be due to the shadow stack series having been in development since before the more extensible clone3() was added rather than anything more deliberate. Add parameters to clone3() specifying the address and size of a shadow stack for the newly created process, we validate that the range specified is accessible to userspace but do not validate that it has been mapped appropriately for use as a shadow stack (normally via map_shadow_stack()). If the shadow stack is specified in this way then the caller is responsible for freeing the memory as with the main stack. If no shadow stack is specified then the existing implicit allocation and freeing behaviour is maintained. If the architecture does not support shadow stacks the shadow stack parameters must be zero, architectures that do support the feature are expected to have the same requirement on individual systems that lack shadow stack support. Update the existing x86 implementation to pay attention to the newly added arguments, in order to maintain compatibility we use the existing behaviour if no shadow stack is specified. Minimal validation is done of the supplied parameters, detailed enforcement is left to when the thread is executed. Since we are now using four fields from the kernel_clone_args we pass that into the shadow stack code rather than individual fields. Signed-off-by: Mark Brown --- arch/x86/include/asm/shstk.h | 11 +++++++---- arch/x86/kernel/process.c | 2 +- arch/x86/kernel/shstk.c | 36 +++++++++++++++++++++++++++++++----- include/linux/sched/task.h | 2 ++ include/uapi/linux/sched.h | 17 ++++++++++++++--- kernel/fork.c | 40 ++++++++++++++++++++++++++++++++++++++-- 6 files changed, 93 insertions(+), 15 deletions(-) diff --git a/arch/x86/include/asm/shstk.h b/arch/x86/include/asm/shstk.h index 42fee8959df7..8be7b0a909c3 100644 --- a/arch/x86/include/asm/shstk.h +++ b/arch/x86/include/asm/shstk.h @@ -6,6 +6,7 @@ #include struct task_struct; +struct kernel_clone_args; struct ksignal; #ifdef CONFIG_X86_USER_SHADOW_STACK @@ -16,8 +17,8 @@ struct thread_shstk { long shstk_prctl(struct task_struct *task, int option, unsigned long arg2); void reset_thread_features(void); -unsigned long shstk_alloc_thread_stack(struct task_struct *p, unsigned long clone_flags, - unsigned long stack_size); +unsigned long shstk_alloc_thread_stack(struct task_struct *p, + const struct kernel_clone_args *args); void shstk_free(struct task_struct *p); int setup_signal_shadow_stack(struct ksignal *ksig); int restore_signal_shadow_stack(void); @@ -26,8 +27,10 @@ static inline long shstk_prctl(struct task_struct *task, int option, unsigned long arg2) { return -EINVAL; } static inline void reset_thread_features(void) {} static inline unsigned long shstk_alloc_thread_stack(struct task_struct *p, - unsigned long clone_flags, - unsigned long stack_size) { return 0; } + const struct kernel_clone_args *args) +{ + return 0; +} static inline void shstk_free(struct task_struct *p) {} static inline int setup_signal_shadow_stack(struct ksignal *ksig) { return 0; } static inline int restore_signal_shadow_stack(void) { return 0; } diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index b6f4e8399fca..a9ca80ea5056 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -207,7 +207,7 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) * is disabled, new_ssp will remain 0, and fpu_clone() will know not to * update it. */ - new_ssp = shstk_alloc_thread_stack(p, clone_flags, args->stack_size); + new_ssp = shstk_alloc_thread_stack(p, args); if (IS_ERR_VALUE(new_ssp)) return PTR_ERR((void *)new_ssp); diff --git a/arch/x86/kernel/shstk.c b/arch/x86/kernel/shstk.c index 59e15dd8d0f8..3ae5c3d657dc 100644 --- a/arch/x86/kernel/shstk.c +++ b/arch/x86/kernel/shstk.c @@ -191,18 +191,44 @@ void reset_thread_features(void) current->thread.features_locked = 0; } -unsigned long shstk_alloc_thread_stack(struct task_struct *tsk, unsigned long clone_flags, - unsigned long stack_size) +unsigned long shstk_alloc_thread_stack(struct task_struct *tsk, + const struct kernel_clone_args *args) { struct thread_shstk *shstk = &tsk->thread.shstk; + unsigned long clone_flags = args->flags; unsigned long addr, size; /* * If shadow stack is not enabled on the new thread, skip any - * switch to a new shadow stack. + * implicit switch to a new shadow stack and reject attempts to + * explciitly specify one. */ - if (!features_enabled(ARCH_SHSTK_SHSTK)) + if (!features_enabled(ARCH_SHSTK_SHSTK)) { + if (args->shadow_stack) + return (unsigned long)ERR_PTR(-EINVAL); + return 0; + } + + /* + * If the user specified a shadow stack then do some basic + * validation and use it. The caller is responsible for + * freeing the shadow stack. + */ + if (args->shadow_stack) { + addr = args->shadow_stack; + size = args->shadow_stack_size; + + if (!IS_ALIGNED(addr, 8)) + return (unsigned long)ERR_PTR(-EINVAL); + if (size < 8) + return (unsigned long)ERR_PTR(-EINVAL); + + shstk->base = 0; + shstk->size = 0; + + return addr + size; + } /* * For CLONE_VFORK the child will share the parents shadow stack. @@ -222,7 +248,7 @@ unsigned long shstk_alloc_thread_stack(struct task_struct *tsk, unsigned long cl if (!(clone_flags & CLONE_VM)) return 0; - size = adjust_shstk_size(stack_size); + size = adjust_shstk_size(args->stack_size); addr = alloc_shstk(0, size, 0, false); if (IS_ERR_VALUE(addr)) return addr; diff --git a/include/linux/sched/task.h b/include/linux/sched/task.h index a23af225c898..94e7cf62be51 100644 --- a/include/linux/sched/task.h +++ b/include/linux/sched/task.h @@ -41,6 +41,8 @@ struct kernel_clone_args { void *fn_arg; struct cgroup *cgrp; struct css_set *cset; + unsigned long shadow_stack; + unsigned long shadow_stack_size; }; /* diff --git a/include/uapi/linux/sched.h b/include/uapi/linux/sched.h index 3bac0a8ceab2..1bd1b956834d 100644 --- a/include/uapi/linux/sched.h +++ b/include/uapi/linux/sched.h @@ -84,6 +84,14 @@ * kernel's limit of nested PID namespaces. * @cgroup: If CLONE_INTO_CGROUP is specified set this to * a file descriptor for the cgroup. + * @shadow_stack: Specify the location of the shadow stack for the + * child process. + * Note, @shadow_stack is expected to point to the + * lowest address. The stack direction will be + * determined by the kernel and set up + * appropriately based on @shadow_stack_size. + * @shadow_stack_size: The size of the shadow stack for the child + * process. * * The structure is versioned by size and thus extensible. * New struct members must go at the end of the struct and @@ -101,12 +109,15 @@ struct clone_args { __aligned_u64 set_tid; __aligned_u64 set_tid_size; __aligned_u64 cgroup; + __aligned_u64 shadow_stack; + __aligned_u64 shadow_stack_size; }; #endif -#define CLONE_ARGS_SIZE_VER0 64 /* sizeof first published struct */ -#define CLONE_ARGS_SIZE_VER1 80 /* sizeof second published struct */ -#define CLONE_ARGS_SIZE_VER2 88 /* sizeof third published struct */ +#define CLONE_ARGS_SIZE_VER0 64 /* sizeof first published struct */ +#define CLONE_ARGS_SIZE_VER1 80 /* sizeof second published struct */ +#define CLONE_ARGS_SIZE_VER2 88 /* sizeof third published struct */ +#define CLONE_ARGS_SIZE_VER3 104 /* sizeof fourth published struct */ /* * Scheduling policies diff --git a/kernel/fork.c b/kernel/fork.c index 3b6d20dfb9a8..bd61aa7353b0 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -3069,7 +3069,9 @@ noinline static int copy_clone_args_from_user(struct kernel_clone_args *kargs, CLONE_ARGS_SIZE_VER1); BUILD_BUG_ON(offsetofend(struct clone_args, cgroup) != CLONE_ARGS_SIZE_VER2); - BUILD_BUG_ON(sizeof(struct clone_args) != CLONE_ARGS_SIZE_VER2); + BUILD_BUG_ON(offsetofend(struct clone_args, shadow_stack_size) != + CLONE_ARGS_SIZE_VER3); + BUILD_BUG_ON(sizeof(struct clone_args) != CLONE_ARGS_SIZE_VER3); if (unlikely(usize > PAGE_SIZE)) return -E2BIG; @@ -3112,6 +3114,8 @@ noinline static int copy_clone_args_from_user(struct kernel_clone_args *kargs, .tls = args.tls, .set_tid_size = args.set_tid_size, .cgroup = args.cgroup, + .shadow_stack = args.shadow_stack, + .shadow_stack_size = args.shadow_stack_size, }; if (args.set_tid && @@ -3152,6 +3156,38 @@ static inline bool clone3_stack_valid(struct kernel_clone_args *kargs) return true; } +/** + * clone3_shadow_stack_valid - check and prepare shadow stack + * @kargs: kernel clone args + * + * Verify that the shadow stack arguments userspace gave us are sane. + */ +static inline bool clone3_shadow_stack_valid(struct kernel_clone_args *kargs) +{ +#ifdef CONFIG_ARCH_HAS_USER_SHADOW_STACK + if (kargs->shadow_stack) { + if (!kargs->shadow_stack_size) + return false; + + /* + * This doesn't validate that the addresses are mapped + * VM_SHADOW_STACK, just that they're mapped at all. + */ + if (!access_ok((void __user *)kargs->shadow_stack, + kargs->shadow_stack_size)) + return false; + } else { + if (kargs->shadow_stack_size) + return false; + } + + return true; +#else + /* The architecture does not support shadow stacks */ + return !kargs->shadow_stack && !kargs->shadow_stack_size; +#endif +} + static bool clone3_args_valid(struct kernel_clone_args *kargs) { /* Verify that no unknown flags are passed along. */ @@ -3174,7 +3210,7 @@ static bool clone3_args_valid(struct kernel_clone_args *kargs) kargs->exit_signal) return false; - if (!clone3_stack_valid(kargs)) + if (!clone3_stack_valid(kargs) || !clone3_shadow_stack_valid(kargs)) return false; return true; From patchwork Mon Oct 23 13:20:42 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 13432852 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3F2B1CDB474 for ; Mon, 23 Oct 2023 13:26:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233564AbjJWN0G (ORCPT ); Mon, 23 Oct 2023 09:26:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51580 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233412AbjJWNZW (ORCPT ); Mon, 23 Oct 2023 09:25:22 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3A54C2D48; Mon, 23 Oct 2023 06:23:45 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5EC4CC4339A; Mon, 23 Oct 2023 13:23:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1698067424; bh=Qe5xNWCPNFdyou1PNmnQ+Jo2U04gFbQ1SqDrhM8USLU=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=EvhhcS01zP+I/nJDBtv2/hU+IN3H+U80vvjB/kXRzcdP8y6qq/+8TZkr6oCUNbR+Y VevtcN+ihfVO+fHtriDTbX9Cqvv1AyKJdabmrj+H1uTbjEJ+uRsVVrD8NRpb1voIly UnirgPUUo8Or97dqZYUPFCUatQXllUANXlN1IPa1wHXNzPvZlhLm2w1UOQlc0CTMPI bhaPucy742dGd+m1gUnO/Q9rNKZgc+W9uKhHVRORwdYncYLj2y3ABmWt5yuqeAnYVd Jj0YUUnuKqrgI8MKAEP8Q33pxva1ioPeLWAMLdFq7/Mdz2hizr/uDKYDRVKAvOVROI 8S4yyhqy6aVSw== From: Mark Brown Date: Mon, 23 Oct 2023 14:20:42 +0100 Subject: [PATCH RFC RFT 3/5] selftests/clone3: Factor more of main loop into test_clone3() MIME-Version: 1.0 Message-Id: <20231023-clone3-shadow-stack-v1-3-d867d0b5d4d0@kernel.org> References: <20231023-clone3-shadow-stack-v1-0-d867d0b5d4d0@kernel.org> In-Reply-To: <20231023-clone3-shadow-stack-v1-0-d867d0b5d4d0@kernel.org> To: "Rick P. Edgecombe" , Deepak Gupta , Szabolcs Nagy , "H.J. Lu" , Florian Weimer , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Daniel Bristot de Oliveira , Valentin Schneider , Christian Brauner , Shuah Khan Cc: linux-kernel@vger.kernel.org, Catalin Marinas , Will Deacon , linux-kselftest@vger.kernel.org, linux-api@vger.kernel.org, Mark Brown X-Mailer: b4 0.13-dev-0438c X-Developer-Signature: v=1; a=openpgp-sha256; l=3743; i=broonie@kernel.org; h=from:subject:message-id; bh=Qe5xNWCPNFdyou1PNmnQ+Jo2U04gFbQ1SqDrhM8USLU=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBlNnPFrNLdzYQAulVZaf402/CEZAeiUf2Mqwx6vlCg zbzu1/WJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCZTZzxQAKCRAk1otyXVSH0CpkB/ wI9vthQaH4b/7GbSX6xay6+qWrwwwjDWC0n05NMHY6+af8/WcriS64FlS/nL/cLW6KrqHuJ19n4j9n zRMGRtp2pldRNuywgaFS2ZODD7W22DOf9Kimlbpef69oZPKLOvSm1kf/GOvgcmeAR3D3Hvk5CjAHjX 24S3K8l2L2uMa1Ix66celhkPYAzqhnxaU3ojXJlXMem+4oAoeOtf231tW1r3oaboLztD5DDIPRkP99 vAclBMxqZggvL8OWelaXHwYnY8k4gN1bIOsH5IN8enKKbW7XAre8N+RzbkSm/yGDt9ETJXqhFulJ8P c67jcjKEpK1BoG03dlMF9V8jg3zxDS X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org In order to make it easier to add more configuration for the tests and more support for runtime detection of when tests can be run pass the structure describing the tests into test_clone3() rather than picking the arguments out of it and have that function do all the per-test work. No functional change. Signed-off-by: Mark Brown --- tools/testing/selftests/clone3/clone3.c | 77 ++++++++++++++++----------------- 1 file changed, 37 insertions(+), 40 deletions(-) diff --git a/tools/testing/selftests/clone3/clone3.c b/tools/testing/selftests/clone3/clone3.c index 9429d361059e..afe383689a67 100644 --- a/tools/testing/selftests/clone3/clone3.c +++ b/tools/testing/selftests/clone3/clone3.c @@ -30,6 +30,19 @@ enum test_mode { CLONE3_ARGS_INVAL_EXIT_SIGNAL_NSIG, }; +typedef bool (*filter_function)(void); +typedef size_t (*size_function)(void); + +struct test { + const char *name; + uint64_t flags; + size_t size; + size_function size_function; + int expected; + enum test_mode test_mode; + filter_function filter; +}; + static int call_clone3(uint64_t flags, size_t size, enum test_mode test_mode) { struct __clone_args args = { @@ -104,30 +117,40 @@ static int call_clone3(uint64_t flags, size_t size, enum test_mode test_mode) return 0; } -static bool test_clone3(uint64_t flags, size_t size, int expected, - enum test_mode test_mode) +static void test_clone3(const struct test *test) { + size_t size; int ret; + if (test->filter && test->filter()) { + ksft_test_result_skip("%s\n", test->name); + return; + } + + if (test->size_function) + size = test->size_function(); + else + size = test->size; + + ksft_print_msg("Running test '%s'\n", test->name); + ksft_print_msg( "[%d] Trying clone3() with flags %#" PRIx64 " (size %zu)\n", - getpid(), flags, size); - ret = call_clone3(flags, size, test_mode); + getpid(), test->flags, size); + ret = call_clone3(test->flags, size, test->test_mode); ksft_print_msg("[%d] clone3() with flags says: %d expected %d\n", - getpid(), ret, expected); - if (ret != expected) { + getpid(), ret, test->expected); + if (ret != test->expected) { ksft_print_msg( "[%d] Result (%d) is different than expected (%d)\n", - getpid(), ret, expected); - return false; + getpid(), ret, test->expected); + ksft_test_result_fail("%s\n", test->name); + return; } - return true; + ksft_test_result_pass("%s\n", test->name); } -typedef bool (*filter_function)(void); -typedef size_t (*size_function)(void); - static bool not_root(void) { if (getuid() != 0) { @@ -143,16 +166,6 @@ static size_t page_size_plus_8(void) return getpagesize() + 8; } -struct test { - const char *name; - uint64_t flags; - size_t size; - size_function size_function; - int expected; - enum test_mode test_mode; - filter_function filter; -}; - static const struct test tests[] = { { .name = "simple clone3()", @@ -301,24 +314,8 @@ int main(int argc, char *argv[]) ksft_set_plan(ARRAY_SIZE(tests)); test_clone3_supported(); - for (i = 0; i < ARRAY_SIZE(tests); i++) { - if (tests[i].filter && tests[i].filter()) { - ksft_test_result_skip("%s\n", tests[i].name); - continue; - } - - if (tests[i].size_function) - size = tests[i].size_function(); - else - size = tests[i].size; - - ksft_print_msg("Running test '%s'\n", tests[i].name); - - ksft_test_result(test_clone3(tests[i].flags, size, - tests[i].expected, - tests[i].test_mode), - "%s\n", tests[i].name); - } + for (i = 0; i < ARRAY_SIZE(tests); i++) + test_clone3(&tests[i]); ksft_finished(); } From patchwork Mon Oct 23 13:20:43 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 13432853 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7DCC9C001E0 for ; Mon, 23 Oct 2023 13:26:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231136AbjJWN0T (ORCPT ); Mon, 23 Oct 2023 09:26:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54968 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231143AbjJWNZ0 (ORCPT ); Mon, 23 Oct 2023 09:25:26 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 93C742D5E; Mon, 23 Oct 2023 06:23:52 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3D6AFC433CD; Mon, 23 Oct 2023 13:23:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1698067431; bh=7YKUNDbMUGXSSUeiwJ4pvwvRXBVAoVFkUMX3lRaprx0=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=PWLcOKFhupYV9/bqMkM4lxQOSU/F1PNenDMqUP2nr8ywu6exhRiNukK+uIE+/Zw/c iU+iSf44SJ9vy/SBSkqAC+YxOtzhvgKTMBqc7TRBMBfZALr2dZDRuRlBDlB3EMaj/S XucKem9LvbMEQhmfOwcurZlACzDVBxyEzVI8wE6X7ANEfKHjtFde5bkUAFu+e3dbOH /HqHCchaB0EKA50WNP80jGAxcGnkzWPPKzvkPADrDoU42JXIisU5Qv9UF/x/aGgspD OAOuOjyXcNYyk8DnhXrvCRIokWRE/LP0SKZKFLnrLfcQThSCE2rzqmDL2Yrq6xTYCD EoRc0h+CkS3sg== From: Mark Brown Date: Mon, 23 Oct 2023 14:20:43 +0100 Subject: [PATCH RFC RFT 4/5] selftests/clone3: Allow tests to flag if -E2BIG is a valid error code MIME-Version: 1.0 Message-Id: <20231023-clone3-shadow-stack-v1-4-d867d0b5d4d0@kernel.org> References: <20231023-clone3-shadow-stack-v1-0-d867d0b5d4d0@kernel.org> In-Reply-To: <20231023-clone3-shadow-stack-v1-0-d867d0b5d4d0@kernel.org> To: "Rick P. Edgecombe" , Deepak Gupta , Szabolcs Nagy , "H.J. Lu" , Florian Weimer , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Daniel Bristot de Oliveira , Valentin Schneider , Christian Brauner , Shuah Khan Cc: linux-kernel@vger.kernel.org, Catalin Marinas , Will Deacon , linux-kselftest@vger.kernel.org, linux-api@vger.kernel.org, Mark Brown X-Mailer: b4 0.13-dev-0438c X-Developer-Signature: v=1; a=openpgp-sha256; l=1887; i=broonie@kernel.org; h=from:subject:message-id; bh=7YKUNDbMUGXSSUeiwJ4pvwvRXBVAoVFkUMX3lRaprx0=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBlNnPGU1TmRkbNZV+PUcum00dEkiIMDqfUoWpyRl5x dSWGE7uJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCZTZzxgAKCRAk1otyXVSH0MsuCA CBCxQGFxf1wABIz0HrZYeAmZPKrdLDZvInZAqm14LQGGXm+SenttiAoWPxh2g9cS5O0r/b5yDwhRk9 0kReorlYqDoFBe8QMuSijaS+TIvVfVyx7Izl8FtllIa0TI6F5H3DGnA7gOzdYHO7uKSSTyXXWxCybO vepIT1S7c8t51eEQox1oI3oHwxuoz9gZUX6+YvtzKAwvVQZkF72BwHB+Eq3hj4eodzm8Y4tYILokmS wKDbliHKE9QXK9IQ8/cxhuoNjpyhf9gmgYjWnfcLfgGUYzJvII30VWOCtWBY4jBF+slAgqS9yLcs5o WnIUWfg74tyCf7jv7//409H63hoNrb X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org The clone_args structure is extensible, with the syscall passing in the length of the structure. Inside the kernel we use copy_struct_from_user() to read the struct but this has the unfortunate side effect of silently accepting some overrun in the structure size providing the extra data is all zeros. This means that we can't discover the clone3() features that the running kernel supports by simply probing with various struct sizes. We need to check this for the benefit of test systems which run newer kselftests on old kernels. Add a flag which can be set on a test to indicate that clone3() may return -E2BIG due to the use of newer struct versions. Currently no tests need this but it will become an issue for testing clone3() support for shadow stacks, the support for shadow stacks is already present on x86. Signed-off-by: Mark Brown --- tools/testing/selftests/clone3/clone3.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/tools/testing/selftests/clone3/clone3.c b/tools/testing/selftests/clone3/clone3.c index afe383689a67..f1802db82e4e 100644 --- a/tools/testing/selftests/clone3/clone3.c +++ b/tools/testing/selftests/clone3/clone3.c @@ -39,6 +39,7 @@ struct test { size_t size; size_function size_function; int expected; + bool e2big_valid; enum test_mode test_mode; filter_function filter; }; @@ -141,6 +142,11 @@ static void test_clone3(const struct test *test) ksft_print_msg("[%d] clone3() with flags says: %d expected %d\n", getpid(), ret, test->expected); if (ret != test->expected) { + if (test->e2big_valid && ret == -E2BIG) { + ksft_print_msg("Test reported -E2BIG\n"); + ksft_test_result_skip("%s\n", test->name); + return; + } ksft_print_msg( "[%d] Result (%d) is different than expected (%d)\n", getpid(), ret, test->expected); From patchwork Mon Oct 23 13:20:44 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 13432862 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 276D8C001E0 for ; Mon, 23 Oct 2023 13:33:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233404AbjJWNdJ (ORCPT ); Mon, 23 Oct 2023 09:33:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46890 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233207AbjJWNdE (ORCPT ); Mon, 23 Oct 2023 09:33:04 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5BD092D6B; Mon, 23 Oct 2023 06:23:59 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3D217C433C9; Mon, 23 Oct 2023 13:23:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1698067439; bh=puDfEO1kotD4qFSC3EfqcfkBLrETnjNBFvX+npWIo7Q=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=vBUUwq+llRi1d+VXUlq4rIne0cNQFC9mBVdsJRmxA6hw1zuo4pa8pz5tFLgRvfIMa AApvDuCZMsviwORUf7q917sqJVGET4k73uK0lHCCy4o8D9qx5GwLpZZwBKkky7XwCK Uku+f6rp+Ukxor9ASvVVOoHHHI2+EFa5ecUAhjDh1hRkjr86MuN2DcRdCQmj011eG+ JueoVwWNcgb5Xq8A51ihzweh8u0tsXmPGoEwH4zgrg82Y1XtJbs8v7gMSvUtBjsXhq 2FBqqm+CfGqRehD9XcYS+C6ls2HtQMWMh0+hfzgiAJ2lW8Z9ebWN4bmdYxhbbKGfxZ oXc1+uktT9USg== From: Mark Brown Date: Mon, 23 Oct 2023 14:20:44 +0100 Subject: [PATCH RFC RFT 5/5] kselftest/clone3: Test shadow stack support MIME-Version: 1.0 Message-Id: <20231023-clone3-shadow-stack-v1-5-d867d0b5d4d0@kernel.org> References: <20231023-clone3-shadow-stack-v1-0-d867d0b5d4d0@kernel.org> In-Reply-To: <20231023-clone3-shadow-stack-v1-0-d867d0b5d4d0@kernel.org> To: "Rick P. Edgecombe" , Deepak Gupta , Szabolcs Nagy , "H.J. Lu" , Florian Weimer , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Daniel Bristot de Oliveira , Valentin Schneider , Christian Brauner , Shuah Khan Cc: linux-kernel@vger.kernel.org, Catalin Marinas , Will Deacon , linux-kselftest@vger.kernel.org, linux-api@vger.kernel.org, Mark Brown X-Mailer: b4 0.13-dev-0438c X-Developer-Signature: v=1; a=openpgp-sha256; l=5429; i=broonie@kernel.org; h=from:subject:message-id; bh=puDfEO1kotD4qFSC3EfqcfkBLrETnjNBFvX+npWIo7Q=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBlNnPGxljfEiyeibQJM6yYflz/X64pYKiaOUmyiJKa TnfCRYOJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCZTZzxgAKCRAk1otyXVSH0KSEB/ 403D86ruPvelfqkNIt6c/l8os/uTJdhOhCAE7zQCqlEgXrWHHmDNSbag3fzY2TseKC4cjC0u4KjcBS FEpJ2Jq9+VlO2yBeJKmMOPvHorf9snbL+rrfzNBNRXYW4QyEBlUtp+iA/eE+6tiZD8ukp6p3oAQ1Se cy6dJmjs7rBkA/9tu1oI7ORqSu+sRXjn6xTY2H/AYrOc2F9GDiEClE1CRMglM1CxEDzqb7zE+e4nk+ jH2flJfgkHQK9eVFgko1GPZblC1zaVqhep54grPsBSoWq5LajKx77sfLZ2CIhyEQlUt0lQzgu1yciW weMEQgloUcc9nBdW3xmbj/nMiwdjKe X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Add basic test coverage for specifying the shadow stack for a newly created thread via clone3(), including coverage of the newly extended argument structure. We detect support for shadow stacks on the running system by attempting to allocate a shadow stack page during initialisation using map_shadow_stack(). Signed-off-by: Mark Brown --- tools/testing/selftests/clone3/clone3.c | 97 +++++++++++++++++++++++ tools/testing/selftests/clone3/clone3_selftests.h | 5 ++ 2 files changed, 102 insertions(+) diff --git a/tools/testing/selftests/clone3/clone3.c b/tools/testing/selftests/clone3/clone3.c index f1802db82e4e..33c35fdfcdfc 100644 --- a/tools/testing/selftests/clone3/clone3.c +++ b/tools/testing/selftests/clone3/clone3.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include #include @@ -21,6 +22,10 @@ #include "../kselftest.h" #include "clone3_selftests.h" +static bool shadow_stack_supported; +static __u64 shadow_stack; +static size_t max_supported_args_size; + enum test_mode { CLONE3_ARGS_NO_TEST, CLONE3_ARGS_ALL_0, @@ -28,6 +33,9 @@ enum test_mode { CLONE3_ARGS_INVAL_EXIT_SIGNAL_NEG, CLONE3_ARGS_INVAL_EXIT_SIGNAL_CSIG, CLONE3_ARGS_INVAL_EXIT_SIGNAL_NSIG, + CLONE3_ARGS_SHADOW_STACK, + CLONE3_ARGS_SHADOW_STACK_SIZE_ONLY, + CLONE3_ARGS_SHADOW_STACK_POINTER_ONLY, }; typedef bool (*filter_function)(void); @@ -44,6 +52,28 @@ struct test { filter_function filter; }; +#ifndef __NR_map_shadow_stack +#define __NR_map_shadow_stack 453 +#endif + +static void test_shadow_stack_supported(void) +{ + shadow_stack = syscall(__NR_map_shadow_stack, 0, getpagesize(), 0); + if (shadow_stack == -1) { + ksft_print_msg("map_shadow_stack() not supported\n"); + } else if ((void *)shadow_stack == MAP_FAILED) { + ksft_print_msg("Failed to map shadow stack\n"); + } else { + ksft_print_msg("Shadow stack supportd\n"); + shadow_stack_supported = true; + } + + /* Dummy stack to use for validating error checks */ + if (!shadow_stack_supported) { + shadow_stack = (__u64)malloc(getpagesize()); + } +} + static int call_clone3(uint64_t flags, size_t size, enum test_mode test_mode) { struct __clone_args args = { @@ -89,6 +119,16 @@ static int call_clone3(uint64_t flags, size_t size, enum test_mode test_mode) case CLONE3_ARGS_INVAL_EXIT_SIGNAL_NSIG: args.exit_signal = 0x00000000000000f0ULL; break; + case CLONE3_ARGS_SHADOW_STACK: + args.shadow_stack = shadow_stack; + args.shadow_stack_size = getpagesize(); + break; + case CLONE3_ARGS_SHADOW_STACK_SIZE_ONLY: + args.shadow_stack_size = getpagesize(); + break; + case CLONE3_ARGS_SHADOW_STACK_POINTER_ONLY: + args.shadow_stack = shadow_stack; + break; } memcpy(&args_ext.args, &args, sizeof(struct __clone_args)); @@ -167,6 +207,26 @@ static bool not_root(void) return false; } +static bool have_shadow_stack(void) +{ + if (shadow_stack_supported) { + ksft_print_msg("Shadow stack supported\n"); + return true; + } + + return false; +} + +static bool no_shadow_stack(void) +{ + if (!shadow_stack_supported) { + ksft_print_msg("Shadow stack not supported\n"); + return true; + } + + return false; +} + static size_t page_size_plus_8(void) { return getpagesize() + 8; @@ -309,6 +369,42 @@ static const struct test tests[] = { .expected = -EINVAL, .test_mode = CLONE3_ARGS_NO_TEST, }, + { + .name = "Shadow stack on system with shadow stack", + .flags = 0, + .size = 0, + .expected = 0, + .e2big_valid = true, + .test_mode = CLONE3_ARGS_SHADOW_STACK, + .filter = no_shadow_stack, + }, + { + .name = "Shadow stack with only size specified", + .flags = 0, + .size = 0, + .expected = -EINVAL, + .e2big_valid = true, + .test_mode = CLONE3_ARGS_SHADOW_STACK_SIZE_ONLY, + .filter = no_shadow_stack, + }, + { + .name = "Shadow stack with only pointer specified", + .flags = 0, + .size = 0, + .expected = -EINVAL, + .e2big_valid = true, + .test_mode = CLONE3_ARGS_SHADOW_STACK_POINTER_ONLY, + .filter = no_shadow_stack, + }, + { + .name = "Shadow stack on system without shadow stack", + .flags = 0, + .size = 0, + .expected = -EINVAL, + .e2big_valid = true, + .test_mode = CLONE3_ARGS_SHADOW_STACK, + .filter = have_shadow_stack, + }, }; int main(int argc, char *argv[]) @@ -319,6 +415,7 @@ int main(int argc, char *argv[]) ksft_print_header(); ksft_set_plan(ARRAY_SIZE(tests)); test_clone3_supported(); + test_shadow_stack_supported(); for (i = 0; i < ARRAY_SIZE(tests); i++) test_clone3(&tests[i]); diff --git a/tools/testing/selftests/clone3/clone3_selftests.h b/tools/testing/selftests/clone3/clone3_selftests.h index e81ffaaee02b..a77db460211b 100644 --- a/tools/testing/selftests/clone3/clone3_selftests.h +++ b/tools/testing/selftests/clone3/clone3_selftests.h @@ -43,6 +43,11 @@ struct __clone_args { __aligned_u64 cgroup; #ifndef CLONE_ARGS_SIZE_VER2 #define CLONE_ARGS_SIZE_VER2 88 /* sizeof third published struct */ +#endif + __aligned_u64 shadow_stack; + __aligned_u64 shadow_stack_size; +#ifndef CLONE_ARGS_SIZE_VER3 +#define CLONE_ARGS_SIZE_VER3 104 /* sizeof fourth published struct */ #endif };