diff options
| author | Nicholas Piggin <npiggin@gmail.com> | 2022-11-27 22:49:39 +1000 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2022-12-02 17:54:09 +1100 |
| commit | 4cefb0f6c555971b3e6544a9b15470f9d1f12089 (patch) | |
| tree | 8d4fd01066bd2c48828ee6053991dce4cdce7440 /arch/powerpc/kernel/process.c | |
| parent | edbd0387f3249cc7e102f86d4852a9a9f3bb1305 (diff) | |
powerpc: split validate_sp into two functions
Most callers just want to validate an arbitrary kernel stack pointer,
some need a particular size. Make the size case the exceptional one
with an extra function.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221127124942.1665522-15-npiggin@gmail.com
Diffstat (limited to 'arch/powerpc/kernel/process.c')
| -rw-r--r-- | arch/powerpc/kernel/process.c | 23 |
1 files changed, 14 insertions, 9 deletions
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index 096b6ea52378..9446bee8ca32 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -2157,9 +2157,12 @@ static inline int valid_emergency_stack(unsigned long sp, struct task_struct *p, return 0; } - -int validate_sp(unsigned long sp, struct task_struct *p, - unsigned long nbytes) +/* + * validate the stack frame of a particular minimum size, used for when we are + * looking at a certain object in the stack beyond the minimum. + */ +int validate_sp_size(unsigned long sp, struct task_struct *p, + unsigned long nbytes) { unsigned long stack_page = (unsigned long)task_stack_page(p); @@ -2175,7 +2178,10 @@ int validate_sp(unsigned long sp, struct task_struct *p, return valid_emergency_stack(sp, p, nbytes); } -EXPORT_SYMBOL(validate_sp); +int validate_sp(unsigned long sp, struct task_struct *p) +{ + return validate_sp_size(sp, p, STACK_FRAME_OVERHEAD); +} static unsigned long ___get_wchan(struct task_struct *p) { @@ -2183,13 +2189,12 @@ static unsigned long ___get_wchan(struct task_struct *p) int count = 0; sp = p->thread.ksp; - if (!validate_sp(sp, p, STACK_FRAME_OVERHEAD)) + if (!validate_sp(sp, p)) return 0; do { sp = READ_ONCE_NOCHECK(*(unsigned long *)sp); - if (!validate_sp(sp, p, STACK_FRAME_OVERHEAD) || - task_is_running(p)) + if (!validate_sp(sp, p) || task_is_running(p)) return 0; if (count > 0) { ip = READ_ONCE_NOCHECK(((unsigned long *)sp)[STACK_FRAME_LR_SAVE]); @@ -2243,7 +2248,7 @@ void __no_sanitize_address show_stack(struct task_struct *tsk, lr = 0; printk("%sCall Trace:\n", loglvl); do { - if (!validate_sp(sp, tsk, STACK_FRAME_OVERHEAD)) + if (!validate_sp(sp, tsk)) break; stack = (unsigned long *) sp; @@ -2270,7 +2275,7 @@ void __no_sanitize_address show_stack(struct task_struct *tsk, * could hold a pt_regs, if that does not fit then it can't * have regs. */ - if (validate_sp(sp, tsk, STACK_SWITCH_FRAME_SIZE) + if (validate_sp_size(sp, tsk, STACK_SWITCH_FRAME_SIZE) && stack[STACK_INT_FRAME_MARKER_LONGS] == STACK_FRAME_REGS_MARKER) { struct pt_regs *regs = (struct pt_regs *) (sp + STACK_INT_FRAME_REGS); |