ocfs2: Fix NULL pointer deref when writing local dquot
commit_dqblk() can write quota info to global file. That is actually a bad
thing to do because if we are just modifying local quota file, we are not
prepared (do not hold proper locks, do not have transaction credits) to do
a modification of the global quota file. So do not use commit_dqblk() and
instead call our writing function directly.
Acked-by: Joel Becker <Joel.Becker@oracle.com>
Signed-off-by: Jan Kara <jack@suse.cz>
diff --git a/fs/ocfs2/quota.h b/fs/ocfs2/quota.h
index 903ffa93..196fcb5 100644
--- a/fs/ocfs2/quota.h
+++ b/fs/ocfs2/quota.h
@@ -109,6 +109,7 @@
struct buffer_head **bh);
int ocfs2_create_local_dquot(struct dquot *dquot);
int ocfs2_local_release_dquot(handle_t *handle, struct dquot *dquot);
+int ocfs2_local_write_dquot(struct dquot *dquot);
extern const struct dquot_operations ocfs2_quota_operations;
extern struct quota_format_type ocfs2_quota_format;
diff --git a/fs/ocfs2/quota_global.c b/fs/ocfs2/quota_global.c
index 7349958..2bb35fe 100644
--- a/fs/ocfs2/quota_global.c
+++ b/fs/ocfs2/quota_global.c
@@ -612,14 +612,13 @@
}
mutex_lock(&sb_dqopt(sb)->dqio_mutex);
status = ocfs2_sync_dquot(dquot);
- mutex_unlock(&sb_dqopt(sb)->dqio_mutex);
if (status < 0)
mlog_errno(status);
/* We have to write local structure as well... */
- dquot_mark_dquot_dirty(dquot);
- status = dquot_commit(dquot);
+ status = ocfs2_local_write_dquot(dquot);
if (status < 0)
mlog_errno(status);
+ mutex_unlock(&sb_dqopt(sb)->dqio_mutex);
ocfs2_commit_trans(osb, handle);
out_ilock:
ocfs2_unlock_global_qf(oinfo, 1);
@@ -658,7 +657,9 @@
mlog_errno(status);
goto out;
}
- status = dquot_commit(dquot);
+ mutex_lock(&sb_dqopt(dquot->dq_sb)->dqio_mutex);
+ status = ocfs2_local_write_dquot(dquot);
+ mutex_unlock(&sb_dqopt(dquot->dq_sb)->dqio_mutex);
ocfs2_commit_trans(osb, handle);
out:
mlog_exit(status);
@@ -831,7 +832,6 @@
struct ocfs2_super *osb = OCFS2_SB(sb);
mlog_entry("id=%u, type=%d", dquot->dq_id, type);
- dquot_mark_dquot_dirty(dquot);
/* In case user set some limits, sync dquot immediately to global
* quota file so that information propagates quicker */
@@ -856,14 +856,14 @@
}
mutex_lock(&sb_dqopt(sb)->dqio_mutex);
status = ocfs2_sync_dquot(dquot);
- mutex_unlock(&sb_dqopt(sb)->dqio_mutex);
if (status < 0) {
mlog_errno(status);
- goto out_trans;
+ goto out_dlock;
}
/* Now write updated local dquot structure */
- status = dquot_commit(dquot);
-out_trans:
+ status = ocfs2_local_write_dquot(dquot);
+out_dlock:
+ mutex_unlock(&sb_dqopt(sb)->dqio_mutex);
ocfs2_commit_trans(osb, handle);
out_ilock:
ocfs2_unlock_global_qf(oinfo, 1);
@@ -915,7 +915,7 @@
}
const struct dquot_operations ocfs2_quota_operations = {
- .write_dquot = ocfs2_write_dquot,
+ /* We never make dquot dirty so .write_dquot is never called */
.acquire_dquot = ocfs2_acquire_dquot,
.release_dquot = ocfs2_release_dquot,
.mark_dirty = ocfs2_mark_dquot_dirty,
diff --git a/fs/ocfs2/quota_local.c b/fs/ocfs2/quota_local.c
index 778947f..551a6bf 100644
--- a/fs/ocfs2/quota_local.c
+++ b/fs/ocfs2/quota_local.c
@@ -892,7 +892,7 @@
}
/* Write dquot to local quota file */
-static int ocfs2_local_write_dquot(struct dquot *dquot)
+int ocfs2_local_write_dquot(struct dquot *dquot)
{
struct super_block *sb = dquot->dq_sb;
struct ocfs2_dquot *od = OCFS2_DQUOT(dquot);
@@ -1309,7 +1309,6 @@
.read_file_info = ocfs2_local_read_info,
.write_file_info = ocfs2_global_write_info,
.free_file_info = ocfs2_local_free_info,
- .commit_dqblk = ocfs2_local_write_dquot,
};
struct quota_format_type ocfs2_quota_format = {