[PATCH 38/75] sysfs: fix i_mutex locking in sysfs_get_dentry()

Greg Kroah-Hartman
2007-10-12T22:40:44Z

From: Tejun Heo <htejun@gmail.com>

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 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index a0da2b0..54ca4bc 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)) {
--
1.5.3.4