diff mbox series

[v3,01/10] ext4: correct grp validation in ext4_mb_good_group

Message ID 20230801143204.2284343-2-shikemeng@huaweicloud.com
State New
Headers
Series A few fixes and cleanups to mballoc |

Commit Message

Kemeng Shi Aug. 1, 2023, 2:31 p.m. UTC 
  Group corruption check will access memory of grp and will trigger kernel
crash if grp is NULL. So do NULL check before corruption check.

Fixes: 5354b2af3406 ("ext4: allow ext4_get_group_info() to fail")
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
---
 fs/ext4/mballoc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 3e34e37392fb..556b7cd27f76 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -2553,7 +2553,7 @@  static bool ext4_mb_good_group(struct ext4_allocation_context *ac,
 
 	BUG_ON(cr < CR_POWER2_ALIGNED || cr >= EXT4_MB_NUM_CRS);
 
-	if (unlikely(EXT4_MB_GRP_BBITMAP_CORRUPT(grp) || !grp))
+	if (unlikely(!grp || EXT4_MB_GRP_BBITMAP_CORRUPT(grp)))
 		return false;
 
 	free = grp->bb_free;