reiserfs: Protect reiserfs_quota_on() with write lock
commit b9e06ef2e8706fe669b51f4364e3aeed58639eb2 upstream.
In reiserfs_quota_on() we do quite some work - for example unpacking
tail of a quota file. Thus we have to hold write lock until a moment
we call back into the quota code.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/fs/reiserfs/super.c b/fs/reiserfs/super.c
index f4f83bf..107f7bd 100644
--- a/fs/reiserfs/super.c
+++ b/fs/reiserfs/super.c
@@ -2170,8 +2170,11 @@
struct reiserfs_transaction_handle th;
int opt = type == USRQUOTA ? REISERFS_USRQUOTA : REISERFS_GRPQUOTA;
- if (!(REISERFS_SB(sb)->s_mount_opt & (1 << opt)))
- return -EINVAL;
+ reiserfs_write_lock(sb);
+ if (!(REISERFS_SB(sb)->s_mount_opt & (1 << opt))) {
+ err = -EINVAL;
+ goto out;
+ }
/* Quotafile not on the same filesystem? */
if (path->dentry->d_sb != sb) {
@@ -2213,8 +2216,10 @@
if (err)
goto out;
}
- err = dquot_quota_on(sb, type, format_id, path);
+ reiserfs_write_unlock(sb);
+ return dquot_quota_on(sb, type, format_id, path);
out:
+ reiserfs_write_unlock(sb);
return err;
}