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| author |  Rick Edgecombe <rick.p.edgecombe@intel.com>
| 2023-06-12 17:10:54 -0700 |
|---|---|---|
| committer |  Dave Hansen <dave.hansen@linux.intel.com>
| 2023-08-02 15:01:50 -0700 |
| commit | 2d39a6add422ac78254927ec2194838c33ae4fb2 (patch) | |
| tree | 466fd0ea8271b73a82b2c6d37770321131b9d4cd /arch/x86/include/asm/shstk.h | |
| parent | x86/shstk: Add user control-protection fault handler (diff) | |
| download | linux-2d39a6add422ac78254927ec2194838c33ae4fb2.tar.gz linux-2d39a6add422ac78254927ec2194838c33ae4fb2.tar.bz2 linux-2d39a6add422ac78254927ec2194838c33ae4fb2.zip | |
x86/shstk: Add user-mode shadow stack support
Introduce basic shadow stack enabling/disabling/allocation routines.
A task's shadow stack is allocated from memory with VM_SHADOW_STACK flag
and has a fixed size of min(RLIMIT_STACK, 4GB).
Keep the task's shadow stack address and size in thread_struct. This will
be copied when cloning new threads, but needs to be cleared during exec,
so add a function to do this.
32 bit shadow stack is not expected to have many users and it will
complicate the signal implementation. So do not support IA32 emulation
or x32.
Co-developed-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Tested-by: Pengfei Xu <pengfei.xu@intel.com>
Tested-by: John Allen <john.allen@amd.com>
Tested-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/all/20230613001108.3040476-29-rick.p.edgecombe%40intel.com
Diffstat (limited to 'arch/x86/include/asm/shstk.h')
| -rw-r--r-- | arch/x86/include/asm/shstk.h | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/arch/x86/include/asm/shstk.h b/arch/x86/include/asm/shstk.h index ec753809f074..2b1f7c9b9995 100644 --- a/arch/x86/include/asm/shstk.h +++ b/arch/x86/include/asm/shstk.h @@ -8,12 +8,19 @@ struct task_struct; #ifdef CONFIG_X86_USER_SHADOW_STACK +struct thread_shstk { + u64 base; + u64 size; +}; + long shstk_prctl(struct task_struct *task, int option, unsigned long features); void reset_thread_features(void); +void shstk_free(struct task_struct *p); #else 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 void shstk_free(struct task_struct *p) {} #endif /* CONFIG_X86_USER_SHADOW_STACK */ #endif /* __ASSEMBLY__ */ |