From 253280267a7f1ced0c434fb24b7bef92d7d22628 Mon Sep 17 00:00:00 2001
From: Tejun Heo <htejun@gmail.com>
Date: Mon, 20 Aug 2007 21:36:29 +0900
Subject: [PATCH] sysfs: fix i_mutex locking in sysfs_get_dentry()
lookup_one_len_kern() should be called with the parent's i_mutex
locked. Fix it.
Spotted by Eric W. Biederman.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
fs/sysfs/dir.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index a0da2b05a754..54ca4bc02dcf 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -130,8 +130,10 @@ struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd)
/* look it up */
parent_dentry = dentry;
+ mutex_lock(&parent_dentry->d_inode->i_mutex);
dentry = lookup_one_len_kern(cur->s_name, parent_dentry,
strlen(cur->s_name));
+ mutex_unlock(&parent_dentry->d_inode->i_mutex);
dput(parent_dentry);
if (IS_ERR(dentry)) {