diff options
| -rw-r--r-- | arch/arm64/include/asm/pointer_auth.h | 7 | ||||
| -rw-r--r-- | arch/arm64/kernel/perf_callchain.c | 6 |
2 files changed, 12 insertions, 1 deletions
diff --git a/arch/arm64/include/asm/pointer_auth.h b/arch/arm64/include/asm/pointer_auth.h index 2a22c03c1540..5ccf49b4dac3 100644 --- a/arch/arm64/include/asm/pointer_auth.h +++ b/arch/arm64/include/asm/pointer_auth.h @@ -69,6 +69,12 @@ static inline void ptrauth_keys_switch(struct ptrauth_keys *keys) */ #define ptrauth_user_pac_mask() GENMASK(54, vabits_user) +/* Only valid for EL0 TTBR0 instruction pointers */ +static inline unsigned long ptrauth_strip_insn_pac(unsigned long ptr) +{ + return ptr & ~ptrauth_user_pac_mask(); +} + #define ptrauth_thread_init_user(tsk) \ do { \ struct task_struct *__ptiu_tsk = (tsk); \ @@ -80,6 +86,7 @@ do { \ ptrauth_keys_switch(&(tsk)->thread_info.keys_user) #else /* CONFIG_ARM64_PTR_AUTH */ +#define ptrauth_strip_insn_pac(lr) (lr) #define ptrauth_thread_init_user(tsk) #define ptrauth_thread_switch(tsk) #endif /* CONFIG_ARM64_PTR_AUTH */ diff --git a/arch/arm64/kernel/perf_callchain.c b/arch/arm64/kernel/perf_callchain.c index bcafd7dcfe8b..94754f07f67a 100644 --- a/arch/arm64/kernel/perf_callchain.c +++ b/arch/arm64/kernel/perf_callchain.c @@ -18,6 +18,7 @@ #include <linux/perf_event.h> #include <linux/uaccess.h> +#include <asm/pointer_auth.h> #include <asm/stacktrace.h> struct frame_tail { @@ -35,6 +36,7 @@ user_backtrace(struct frame_tail __user *tail, { struct frame_tail buftail; unsigned long err; + unsigned long lr; /* Also check accessibility of one struct frame_tail beyond */ if (!access_ok(VERIFY_READ, tail, sizeof(buftail))) @@ -47,7 +49,9 @@ user_backtrace(struct frame_tail __user *tail, if (err) return NULL; - perf_callchain_store(entry, buftail.lr); + lr = ptrauth_strip_insn_pac(buftail.lr); + + perf_callchain_store(entry, lr); /* * Frame pointers should strictly progress back up the stack |