reiserfs: Fix memory leak of journal device string

BugLink: https://bugs.launchpad.net/bugs/1864774

commit 5474ca7d upstream.

When a filesystem is mounted with jdev mount option, we store the
journal device name in an allocated string in superblock. However we
fail to ever free that string. Fix it.

Reported-by: syzbot+1c6756baf4b16b94d2a6@syzkaller.appspotmail.com
Fixes: c3aa0776 ("reiserfs: Properly display mount options in /proc/mounts")
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

fs/reiserfs/super.c

@@ -599,6 +599,7 @@ static void reiserfs_put_super(struct super_block *s)
 	reiserfs_write_unlock(s);
 	mutex_destroy(&REISERFS_SB(s)->lock);
 	destroy_workqueue(REISERFS_SB(s)->commit_wq);
+	kfree(REISERFS_SB(s)->s_jdev);
 	kfree(s->s_fs_info);
 	s->s_fs_info = NULL;
 }
@@ -2208,6 +2209,7 @@ static int reiserfs_fill_super(struct super_block *s, void *data, int silent)
 			kfree(qf_names[j]);
 	}
 #endif
+	kfree(sbi->s_jdev);
 	kfree(sbi);
 
 	s->s_fs_info = NULL;