[PATCH] jffs2: unlock f->sem on error in jffs2_new_inode()

[PATCH] jffs2: unlock f->sem on error in jffs2_new_inode()

[Wang Nan]

From: Wang Guoli <andy.wangguoli@huawei.com>

If jffs2_new_inode() succeeds, it returns with f->sem held, and
the caller is responsible for releasing the lock. If it fails,
it still returns with the lock held, but the caller won't release
the lock, which will lead to deadlock.

Fix it by releasing the lock in jffs2_new_inode() on error.

Cc: <stable@vger.kernel.org> # 2.6.34+
Signed-off-by: Wang Guoli <andy.wangguoli@huawei.com>
---
 fs/jffs2/fs.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/fs/jffs2/fs.c b/fs/jffs2/fs.c
index 09b3ed4..2b91675 100644
--- a/fs/jffs2/fs.c
+++ b/fs/jffs2/fs.c
@@ -456,12 +456,14 @@ struct inode *jffs2_new_inode (struct inode *dir_i, umode_t mode, struct jffs2_r
 	   The umask is only applied if there's no default ACL */
 	ret = jffs2_init_acl_pre(dir_i, inode, &mode);
 	if (ret) {
-	    make_bad_inode(inode);
-	    iput(inode);
-	    return ERR_PTR(ret);
+		mutex_unlock(&f->sem);
+		make_bad_inode(inode);
+		iput(inode);
+		return ERR_PTR(ret);
 	}
 	ret = jffs2_do_new_inode (c, f, mode, ri);
 	if (ret) {
+		mutex_unlock(&f->sem);
 		make_bad_inode(inode);
 		iput(inode);
 		return ERR_PTR(ret);
@@ -478,6 +480,7 @@ struct inode *jffs2_new_inode (struct inode *dir_i, umode_t mode, struct jffs2_r
 	inode->i_size = 0;
 
 	if (insert_inode_locked(inode) < 0) {
+		mutex_unlock(&f->sem);
 		make_bad_inode(inode);
 		iput(inode);
 		return ERR_PTR(-EINVAL);
-- 
1.8.4

Re: [PATCH] jffs2: unlock f->sem on error in jffs2_new_inode()

[Li Zefan]

The patch should be sent to jffs2 mainling list, which is
linux-mtd@lists.infradead.org.

It's not needed to cc stable mailing list. Actually I think it's
better not to.

On 2013/12/18 10:14, Wang Nan wrote:
> From: Wang Guoli <andy.wangguoli@huawei.com>
> 
> If jffs2_new_inode() succeeds, it returns with f->sem held, and
> the caller is responsible for releasing the lock. If it fails,
> it still returns with the lock held, but the caller won't release
> the lock, which will lead to deadlock.
> 
> Fix it by releasing the lock in jffs2_new_inode() on error.
> 
> Cc: <stable@vger.kernel.org> # 2.6.34+
> Signed-off-by: Wang Guoli <andy.wangguoli@huawei.com>

You should also sign the patch.

> ---
>  fs/jffs2/fs.c | 9 ++++++---
>  1 file changed, 6 insertions(+), 3 deletions(-)