[PATCH v2 1/2] quota: Properly disable quotas when add_dquot_ref() fails

From: Ye Bin
Date: Mon Jun 05 2023 - 10:11:57 EST


From: Jan Kara <jack@xxxxxxx>

When add_dquot_ref() fails (usually due to IO error or ENOMEM), we want
to disable quotas we are trying to enable. However dquot_disable() call
was passed just the flags we are enabling so in case flags ==
DQUOT_USAGE_ENABLED dquot_disable() call will just fail with EINVAL
instead of properly disabling quotas. Fix the problem by always passing
DQUOT_LIMITS_ENABLED | DQUOT_USAGE_ENABLED to dquot_disable() in this
case.

Reported-and-tested-by: Ye Bin <yebin10@xxxxxxxxxx>
Reported-by: syzbot+e633c79ceaecbf479854@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Jan Kara <jack@xxxxxxx>
---
fs/quota/dquot.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
index ffd40dc3e4e9..6beceed34e08 100644
--- a/fs/quota/dquot.c
+++ b/fs/quota/dquot.c
@@ -2420,7 +2420,8 @@ int dquot_load_quota_sb(struct super_block *sb, int type, int format_id,

error = add_dquot_ref(sb, type);
if (error)
- dquot_disable(sb, type, flags);
+ dquot_disable(sb, type,
+ DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);

return error;
out_fmt:
--
2.31.1