[PATCH 5.4 269/320] ext4: make sure quota gets properly shutdown on error

Greg Kroah-Hartman
2022-01-24T19:41:10Z

From: Jan Kara <jack@suse.cz>

commit 15fc69bbbbbc8c72e5f6cc4e1be0f51283c5448e upstream.

When we hit an error when enabling quotas and setting inode flags, we do
not properly shutdown quota subsystem despite returning error from
Q_QUOTAON quotactl. This can lead to some odd situations like kernel
using quota file while it is still writeable for userspace. Make sure we
properly cleanup the quota subsystem in case of error.

Signed-off-by: Jan Kara <jack@suse.cz>
Cc: stable@kernel.org
Link: https://lore.kernel.org/r/20211007155336.12493-2-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/ext4/super.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -5912,10 +5912,7 @@ static int ext4_quota_on(struct super_bl

lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
err = dquot_quota_on(sb, type, format_id, path);
- if (err) {
- lockdep_set_quota_inode(path->dentry->d_inode,
- I_DATA_SEM_NORMAL);
- } else {
+ if (!err) {
struct inode *inode = d_inode(path->dentry);
handle_t *handle;

@@ -5935,7 +5932,12 @@ static int ext4_quota_on(struct super_bl
ext4_journal_stop(handle);
unlock_inode:
inode_unlock(inode);
+ if (err)
+ dquot_quota_off(sb, type);
}
+ if (err)
+ lockdep_set_quota_inode(path->dentry->d_inode,
+ I_DATA_SEM_NORMAL);
return err;
}