free_anon_vma_name() is missing a check for anonymous shmem VMA which
leads to a memory leak due to refcount not being dropped. Fix this by
calling anon_vma_name_put() unconditionally. It will free vma->anon_name
whenever it's non-NULL.
Fixes: d09e8ca6cb93 ("mm: anonymous shared memory naming")
Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Suggested-by: David Hildenbrand <david@xxxxxxxxxx>
Reported-by: syzbot+91edf9178386a07d06a7@xxxxxxxxxxxxxxxxxxxxxxxxx
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: Pasha Tatashin <pasha.tatashin@xxxxxxxxxx>
---
applies over mm-hotfixes-unstable branch of
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm tree after reverting
the original version of this patch.
include/linux/mm_inline.h | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/include/linux/mm_inline.h b/include/linux/mm_inline.h
index e8ed225d8f7c..ff3f3f23f649 100644
--- a/include/linux/mm_inline.h
+++ b/include/linux/mm_inline.h
@@ -413,8 +413,7 @@ static inline void free_anon_vma_name(struct vm_area_struct *vma)
* Not using anon_vma_name because it generates a warning if mmap_lock
* is not held, which might be the case here.
*/
- if (!vma->vm_file)
- anon_vma_name_put(vma->anon_name);
+ anon_vma_name_put(vma->anon_name);
}
static inline bool anon_vma_name_eq(struct anon_vma_name *anon_name1,
--
2.39.0.314.g84b9a713c41-goog
