2008-04-02 09:10:08

by Jan Kara

[permalink] [raw]
Subject: [PATCH] ext4: Fix hang on umount with quotas when journal is aborted

Call dquot_drop() from ext4_dquot_drop() even if we fail to start a
transaction. Otherwise we never get to dropping references to quota structures
from the inode and umount will hang indefinitely. Thanks to Payphone LIOU for
spotting the problem.

Signed-off-by: Jan Kara <[email protected]>
CC: Payphone LIOU <[email protected]>

I'm not sure if this should go through ext4 patch queue or through Andrew.
It should not collide with anything so it probably does not matter much...

fs/ext4/super.c | 8 +++++++-
1 files changed, 7 insertions(+), 1 deletions(-)

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 13383ba..286acec 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -3039,8 +3039,14 @@ static int ext4_dquot_drop(struct inode *inode)

/* We may delete quota structure so we need to reserve enough blocks */
handle = ext4_journal_start(inode, 2*EXT4_QUOTA_DEL_BLOCKS(inode->i_sb));
- if (IS_ERR(handle))
+ if (IS_ERR(handle)) {
+ /*
+ * We call dquot_drop() anyway to at least release references
+ * to quota structures so that umount does not hang.
+ */
+ dquot_drop(inode);
return PTR_ERR(handle);
+ }
ret = dquot_drop(inode);
err = ext4_journal_stop(handle);
if (!ret)