diff options
| -rw-r--r-- | arch/arm64/kernel/sleep.S | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/kprobes/core.c | 4 | ||||
| -rw-r--r-- | include/linux/kasan.h | 2 | ||||
| -rw-r--r-- | mm/kasan/kasan.c | 22 |
4 files changed, 26 insertions, 4 deletions
diff --git a/arch/arm64/kernel/sleep.S b/arch/arm64/kernel/sleep.S index b8799e7c79de..1bec41b5fda3 100644 --- a/arch/arm64/kernel/sleep.S +++ b/arch/arm64/kernel/sleep.S @@ -135,7 +135,7 @@ ENTRY(_cpu_resume) #ifdef CONFIG_KASAN mov x0, sp - bl kasan_unpoison_remaining_stack + bl kasan_unpoison_task_stack_below #endif ldp x19, x20, [x29, #16] diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c index f423b0ef23a7..d9d8d16b69db 100644 --- a/arch/x86/kernel/kprobes/core.c +++ b/arch/x86/kernel/kprobes/core.c @@ -50,6 +50,7 @@ #include <linux/kallsyms.h> #include <linux/ftrace.h> #include <linux/frame.h> +#include <linux/kasan.h> #include <asm/text-patching.h> #include <asm/cacheflush.h> @@ -1081,6 +1082,9 @@ void jprobe_return(void) { struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); + /* Unpoison stack redzones in the frames we are going to jump over. */ + kasan_unpoison_stack_above_sp_to(kcb->jprobe_saved_sp); + asm volatile ( #ifdef CONFIG_X86_64 " xchg %%rbx,%%rsp \n" diff --git a/include/linux/kasan.h b/include/linux/kasan.h index d600303306eb..820c0ad54a01 100644 --- a/include/linux/kasan.h +++ b/include/linux/kasan.h @@ -44,6 +44,7 @@ static inline void kasan_disable_current(void) void kasan_unpoison_shadow(const void *address, size_t size); void kasan_unpoison_task_stack(struct task_struct *task); +void kasan_unpoison_stack_above_sp_to(const void *watermark); void kasan_alloc_pages(struct page *page, unsigned int order); void kasan_free_pages(struct page *page, unsigned int order); @@ -85,6 +86,7 @@ size_t kasan_metadata_size(struct kmem_cache *cache); static inline void kasan_unpoison_shadow(const void *address, size_t size) {} static inline void kasan_unpoison_task_stack(struct task_struct *task) {} +static inline void kasan_unpoison_stack_above_sp_to(const void *watermark) {} static inline void kasan_enable_current(void) {} static inline void kasan_disable_current(void) {} diff --git a/mm/kasan/kasan.c b/mm/kasan/kasan.c index 88af13c00d3c..70c009741aab 100644 --- a/mm/kasan/kasan.c +++ b/mm/kasan/kasan.c @@ -34,6 +34,7 @@ #include <linux/string.h> #include <linux/types.h> #include <linux/vmalloc.h> +#include <linux/bug.h> #include "kasan.h" #include "../slab.h" @@ -62,7 +63,7 @@ void kasan_unpoison_shadow(const void *address, size_t size) } } -static void __kasan_unpoison_stack(struct task_struct *task, void *sp) +static void __kasan_unpoison_stack(struct task_struct *task, const void *sp) { void *base = task_stack_page(task); size_t size = sp - base; @@ -77,9 +78,24 @@ void kasan_unpoison_task_stack(struct task_struct *task) } /* Unpoison the stack for the current task beyond a watermark sp value. */ -asmlinkage void kasan_unpoison_remaining_stack(void *sp) +asmlinkage void kasan_unpoison_task_stack_below(const void *watermark) { - __kasan_unpoison_stack(current, sp); + __kasan_unpoison_stack(current, watermark); +} + +/* + * Clear all poison for the region between the current SP and a provided + * watermark value, as is sometimes required prior to hand-crafted asm function + * returns in the middle of functions. + */ +void kasan_unpoison_stack_above_sp_to(const void *watermark) +{ + const void *sp = __builtin_frame_address(0); + size_t size = watermark - sp; + + if (WARN_ON(sp > watermark)) + return; + kasan_unpoison_shadow(sp, size); } /* |