[PATCH 3.12 163/181] Btrfs: fix double free in find_lock_delalloc_range

Jiri Slaby
2014-06-30T12:53:22Z

From: Chris Mason <clm@fb.com>

3.12-stable review patch. If anyone has any objections, please let me know.

===============

commit 7d78874273463a784759916fc3e0b4e2eb141c70 upstream.

We need to NULL the cached_state after freeing it, otherwise
we might free it again if find_delalloc_range doesn't find anything.

Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
fs/btrfs/extent_io.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 51731b76900d..0d611d1e2e34 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -1645,6 +1645,7 @@ again:
* shortening the size of the delalloc range we're searching
*/
free_extent_state(cached_state);
+ cached_state = NULL;
if (!loops) {
max_bytes = PAGE_CACHE_SIZE;
loops = 1;
--
2.0.0