diff options
| author | Andrey Konovalov <andreyknvl@google.com> | 2023-12-19 22:19:51 +0100 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-12-29 20:58:41 +0100 |
| commit | a414d4286f3400aa05631c4931eb3feba83e29e8 (patch) | |
| tree | 44095dcb97d398bb82d6de0ad8a9f8f823599495 /mm/kasan/kasan.h | |
| parent | lib/stackdepot: add printk_deferred_enter/exit guards (diff) | |
| download | linux-a414d4286f3400aa05631c4931eb3feba83e29e8.tar.xz linux-a414d4286f3400aa05631c4931eb3feba83e29e8.zip | |
kasan: handle concurrent kasan_record_aux_stack calls
kasan_record_aux_stack can be called concurrently on the same object.
This might lead to a race condition when rotating the saved aux stack
trace handles, which in turns leads to incorrect accounting of stack depot
handles and refcount underflows in the stack depot code.
Fix by introducing a raw spinlock to protect the aux stack trace handles
in kasan_record_aux_stack.
Link: https://lkml.kernel.org/r/1606b960e2f746862d1f459515972f9695bf448a.1703020707.git.andreyknvl@google.com
Fixes: 773688a6cb24 ("kasan: use stack_depot_put for Generic mode")
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Reported-by: syzbot+186b55175d8360728234@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/000000000000784b1c060b0074a2@google.com/
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/kasan/kasan.h')
| -rw-r--r-- | mm/kasan/kasan.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h index 5e298e3ac909..69e4f5e58e33 100644 --- a/mm/kasan/kasan.h +++ b/mm/kasan/kasan.h @@ -6,6 +6,7 @@ #include <linux/kasan.h> #include <linux/kasan-tags.h> #include <linux/kfence.h> +#include <linux/spinlock.h> #include <linux/stackdepot.h> #if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS) @@ -249,6 +250,13 @@ struct kasan_global { struct kasan_alloc_meta { struct kasan_track alloc_track; /* Free track is stored in kasan_free_meta. */ + /* + * aux_lock protects aux_stack from accesses from concurrent + * kasan_record_aux_stack calls. It is a raw spinlock to avoid sleeping + * on RT kernels, as kasan_record_aux_stack_noalloc can be called from + * non-sleepable contexts. + */ + raw_spinlock_t aux_lock; depot_stack_handle_t aux_stack[2]; }; |