From 6a32876747f1aa378598564a64c174f75d915ff7 Mon Sep 17 00:00:00 2001 From: Changwei Ge Date: Fri, 2 Nov 2018 15:48:15 -0700 Subject: [PATCH] ocfs2: fix a misuse a of brelse after failing ocfs2_check_dir_entry commit 29aa30167a0a2e6045a0d6d2e89d8168132333d5 upstream. Somehow, file system metadata was corrupted, which causes ocfs2_check_dir_entry() to fail in function ocfs2_dir_foreach_blk_el(). According to the original design intention, if above happens we should skip the problematic block and continue to retrieve dir entry. But there is obviouse misuse of brelse around related code. After failure of ocfs2_check_dir_entry(), current code just moves to next position and uses the problematic buffer head again and again during which the problematic buffer head is released for multiple times. I suppose, this a serious issue which is long-lived in ocfs2. This may cause other file systems which is also used in a the same host insane. So we should also consider about bakcporting this patch into linux -stable. Link: http://lkml.kernel.org/r/HK2PR06MB045211675B43EED794E597B6D56E0@HK2PR06MB0452.apcprd06.prod.outlook.com Signed-off-by: Changwei Ge Suggested-by: Changkuo Shi Reviewed-by: Andrew Morton Cc: Mark Fasheh Cc: Joel Becker Cc: Junxiao Bi Cc: Joseph Qi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Ben Hutchings --- fs/ocfs2/dir.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/fs/ocfs2/dir.c b/fs/ocfs2/dir.c index 0717662b4aef..0165e4ff163c 100644 --- a/fs/ocfs2/dir.c +++ b/fs/ocfs2/dir.c @@ -1906,8 +1906,7 @@ static int ocfs2_dir_foreach_blk_el(struct inode *inode, /* On error, skip the f_pos to the next block. */ ctx->pos = (ctx->pos | (sb->s_blocksize - 1)) + 1; - brelse(bh); - continue; + break; } if (le64_to_cpu(de->inode)) { unsigned char d_type = DT_UNKNOWN;