diff options
| author | Christophe Leroy <christophe.leroy@csgroup.eu> | 2024-08-20 14:26:54 +0200 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2024-08-30 21:30:20 +1000 |
| commit | dca5b1d69aea36ab559d9ca13729370007c60df1 (patch) | |
| tree | af3973e17705ec58df620ee5610c0ba593bb1a5b | |
| parent | 062e825a336017c0334c7497690826c95aa1a84f (diff) | |
powerpc/32: Implement validation of emergency stack
VMAP stack added an emergency stack on powerpc/32 for when there is
a stack overflow, but failed to add stack validation for that
emergency stack. That validation is required for show stack.
Implement it.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/2439d50b019f758db4a6d7b238b06441ab109799.1724156805.git.christophe.leroy@csgroup.eu
| -rw-r--r-- | arch/powerpc/include/asm/thread_info.h | 4 | ||||
| -rw-r--r-- | arch/powerpc/kernel/process.c | 20 |
2 files changed, 22 insertions, 2 deletions
diff --git a/arch/powerpc/include/asm/thread_info.h b/arch/powerpc/include/asm/thread_info.h index 15c5691dd218..6ebca2996f18 100644 --- a/arch/powerpc/include/asm/thread_info.h +++ b/arch/powerpc/include/asm/thread_info.h @@ -226,6 +226,10 @@ static inline int arch_within_stack_frames(const void * const stack, return BAD_STACK; } +#ifdef CONFIG_PPC32 +extern void *emergency_ctx[]; +#endif + #endif /* !__ASSEMBLY__ */ #endif /* __KERNEL__ */ diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index e7b70c2cc001..ff61a3e7984c 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -2175,10 +2175,10 @@ static inline int valid_irq_stack(unsigned long sp, struct task_struct *p, return 0; } +#ifdef CONFIG_PPC64 static inline int valid_emergency_stack(unsigned long sp, struct task_struct *p, unsigned long nbytes) { -#ifdef CONFIG_PPC64 unsigned long stack_page; unsigned long cpu = task_cpu(p); @@ -2206,10 +2206,26 @@ static inline int valid_emergency_stack(unsigned long sp, struct task_struct *p, if (sp >= stack_page && sp <= stack_page + THREAD_SIZE - nbytes) return 1; # endif -#endif return 0; } +#else +static inline int valid_emergency_stack(unsigned long sp, struct task_struct *p, + unsigned long nbytes) +{ + unsigned long stack_page; + unsigned long cpu = task_cpu(p); + + if (!IS_ENABLED(CONFIG_VMAP_STACK)) + return 0; + + stack_page = (unsigned long)emergency_ctx[cpu] - THREAD_SIZE; + if (sp >= stack_page && sp <= stack_page + THREAD_SIZE - nbytes) + return 1; + + return 0; +} +#endif /* * validate the stack frame of a particular minimum size, used for when we are |