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| author | Sami Tolvanen <samitolvanen@google.com> | 2020-04-27 19:00:16 +0300 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2020-05-15 18:35:50 +0300 |
| commit | 5287569a790d2546a06db07e391bf84b8bd6cf51 (patch) | |
| tree | 137dc42c9e15afc1b7880798d2ea1ed146301211 /arch/arm64/include/asm/scs.h | |
| parent | 9654736891c3ac6a60b52ce70d33cf57cf95bff7 (diff) | |
| download | linux-5287569a790d2546a06db07e391bf84b8bd6cf51.tar.xz | |
arm64: Implement Shadow Call Stack
This change implements shadow stack switching, initial SCS set-up,
and interrupt shadow stacks for arm64.
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64/include/asm/scs.h')
| -rw-r--r-- | arch/arm64/include/asm/scs.h | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/scs.h b/arch/arm64/include/asm/scs.h new file mode 100644 index 000000000000..96549353b0cb --- /dev/null +++ b/arch/arm64/include/asm/scs.h @@ -0,0 +1,46 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_SCS_H +#define _ASM_SCS_H + +#ifdef __ASSEMBLY__ + +#ifdef CONFIG_SHADOW_CALL_STACK + .macro scs_load tsk, tmp + ldp x18, \tmp, [\tsk, #TSK_TI_SCS_BASE] + add x18, x18, \tmp + .endm + + .macro scs_save tsk, tmp + ldr \tmp, [\tsk, #TSK_TI_SCS_BASE] + sub \tmp, x18, \tmp + str \tmp, [\tsk, #TSK_TI_SCS_OFFSET] + .endm +#else + .macro scs_load tsk, tmp + .endm + + .macro scs_save tsk, tmp + .endm +#endif /* CONFIG_SHADOW_CALL_STACK */ + +#else /* __ASSEMBLY__ */ + +#include <linux/scs.h> + +#ifdef CONFIG_SHADOW_CALL_STACK + +static inline void scs_overflow_check(struct task_struct *tsk) +{ + if (unlikely(scs_corrupted(tsk))) + panic("corrupted shadow stack detected inside scheduler\n"); +} + +#else /* CONFIG_SHADOW_CALL_STACK */ + +static inline void scs_overflow_check(struct task_struct *tsk) {} + +#endif /* CONFIG_SHADOW_CALL_STACK */ + +#endif /* __ASSEMBLY __ */ + +#endif /* _ASM_SCS_H */ |