[-v2,mm,3/4] kasan: memset free track in qlink_free

Message ID 39bbc4d0bc72dfaf02f9dc63ee6f25a8f3a1719c.1702514411.git.andreyknvl@google.com
State New
Headers
Series lib/stackdepot, kasan: fixes for stack eviction series |

Commit Message

andrey.konovalov@linux.dev Dec. 14, 2023, 12:47 a.m. UTC
  From: Andrey Konovalov <andreyknvl@google.com>

Instead of only zeroing out the stack depot handle when evicting the
free stack trace in qlink_free, zero out the whole track.

Do this just to produce a similar effect for alloc and free meta. The
other fields of the free track besides the stack trace handle are
considered invalid at this point anyway, so no harm in zeroing them out.

Fixes: 773688a6cb24 ("kasan: use stack_depot_put for Generic mode")
Reviewed-by: Marco Elver <elver@google.com>
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
---
 mm/kasan/quarantine.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
  

Patch

diff --git a/mm/kasan/quarantine.c b/mm/kasan/quarantine.c
index 265ca2bbe2dd..782e045da911 100644
--- a/mm/kasan/quarantine.c
+++ b/mm/kasan/quarantine.c
@@ -157,7 +157,7 @@  static void qlink_free(struct qlist_node *qlink, struct kmem_cache *cache)
 	if (free_meta &&
 	    *(u8 *)kasan_mem_to_shadow(object) == KASAN_SLAB_FREETRACK) {
 		stack_depot_put(free_meta->free_track.stack);
-		free_meta->free_track.stack = 0;
+		__memset(&free_meta->free_track, 0, sizeof(free_meta->free_track));
 	}
 
 	/*