Re: [PATCH 04/12] gfs2: properly initial file_lock used for unlock.

From: Jeff Layton <jlayton@kernel.org>
To: NeilBrown <neilb@suse.com>, Alexander Viro <viro@zeniv.linux.org.uk>
Cc: "J. Bruce Fields" <bfields@fieldses.org>,
	Martin Wilck <mwilck@suse.de>,
	linux-fsdevel@vger.kernel.org,
	Frank Filz <ffilzlnx@mindspring.com>,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 04/12] gfs2: properly initial file_lock used for unlock.
Date: Mon, 05 Nov 2018 07:18:56 -0500	[thread overview]
Message-ID: <efbaeb736e4738bb7a0e2f8529bf1db8459bbe56.camel@kernel.org> (raw)
In-Reply-To: <154138144777.31651.4516223215037533891.stgit@noble>

On Mon, 2018-11-05 at 12:30 +1100, NeilBrown wrote:
> Rather than assuming all-zeros is sufficient, use the available API to
> initialize the file_lock structure use for unlock.
> VFS-level changes will soon make it important that the
> list_heads in file_lock are always properly initialized.
> 
> Signed-off-by: NeilBrown <neilb@suse.com>
> ---
>  fs/gfs2/file.c |   10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
> index 45a17b770d97..271f847705e3 100644
> --- a/fs/gfs2/file.c
> +++ b/fs/gfs2/file.c
> @@ -1199,13 +1199,13 @@ static int do_flock(struct file *file, int cmd, struct file_lock *fl)
>  	mutex_lock(&fp->f_fl_mutex);
>  
>  	if (gfs2_holder_initialized(fl_gh)) {
> +		struct file_lock request;
>  		if (fl_gh->gh_state == state)
>  			goto out;
> -		locks_lock_file_wait(file,
> -				     &(struct file_lock) {
> -					     .fl_type = F_UNLCK,
> -					     .fl_flags = FL_FLOCK
> -				     });
> +		locks_init_lock(&request);
> +		request.fl_type = F_UNLOCK;

F_UNLCK ?

The ocfs2 patch has the same bug.

> +		request.fl_flags = FL_FLOCK;
> +		locks_lock_file_wait(file, &request);
>  		gfs2_glock_dq(fl_gh);
>  		gfs2_holder_reinit(state, flags, fl_gh);
>  	} else {
> 
> 

-- 
Jeff Layton <jlayton@kernel.org>