Hi Andrew,

I've run all 4 of these patches (for the second one, I'm using my latest
version; I'll resend it formally) through a little bit of testing here.

Hi Wang,

Thanks for the patch.

On Wed, Feb 12, 2014 at 12:44:54PM -0800, Andrew Morton wrote:
> From: Wang Guoli <andy.wanggu...@huawei.com>
> Subject: jffs2: unlock f->sem on error in jffs2_new_inode()
> 
> 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.

Have you actually seen a deadlock for this? AFAICT, the error cases for
jffs2_new_inode() all occur before anyone else actually has a reference
to the inode, so I don't expect that we should see the deadlock.

> Fix it by releasing the lock in jffs2_new_inode() on error.
> 
> Signed-off-by: Wang Guoli <andy.wanggu...@huawei.com>
> Signed-off-by: Wang Nan <wangn...@huawei.com>
> Cc: Artem Bityutskiy <artem.bityuts...@linux.intel.com>
> Cc: David Woodhouse <dw...@infradead.org>
> Cc: Wang Guoli <andy.wanggu...@huawei.com>
> Cc: Brian Norris <computersforpe...@gmail.com>
> Cc: <stable@vger.kernel.org> # 2.6.34+
> Signed-off-by: Andrew Morton <a...@linux-foundation.org>
> ---
> 
>  fs/jffs2/fs.c |    9 ++++++---
>  1 file changed, 6 insertions(+), 3 deletions(-)
> 
> diff -puN fs/jffs2/fs.c~jffs2-unlock-f-sem-on-error-in-jffs2_new_inode 
> fs/jffs2/fs.c
> --- a/fs/jffs2/fs.c~jffs2-unlock-f-sem-on-error-in-jffs2_new_inode
> +++ a/fs/jffs2/fs.c
> @@ -457,12 +457,14 @@ struct inode *jffs2_new_inode (struct in
>          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);
> @@ -479,6 +481,7 @@ struct inode *jffs2_new_inode (struct in
>       inode->i_size = 0;
>  
>       if (insert_inode_locked(inode) < 0) {
> +             mutex_unlock(&f->sem);
>               make_bad_inode(inode);
>               iput(inode);
>               return ERR_PTR(-EINVAL);

Brian
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