Group corruption check will access memory of grp and will trigger kernel crash if grp is NULL. So do NULL check before corruption check. Signed-off-by: Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx> --- fs/ext4/mballoc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 3ab37533349f..90ffabac100b 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -2554,7 +2554,7 @@ 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 (!grp || unlikely(EXT4_MB_GRP_BBITMAP_CORRUPT(grp))) return false; free = grp->bb_free; -- 2.30.0
