Re: [PATCH] lockd: Show pid of lockd for remote locks

["J. Bruce Fields" <bfields@fieldses.org>]

On Thu, Nov 01, 2018 at 01:39:49PM -0400, Benjamin Coddington wrote:
> Commit 9d5b86ac13c5 ("fs/locks: Remove fl_nspid and use fs-specific l_pid
> for remote locks") specified that the l_pid returned for F_GETLK on a local
> file that has a remote lock should be the pid of the lock manager process.
> That commit, while updating other filesystems, failed to update lockd, such
> that locks created by lockd had their fl_pid set to that of the remote
> process holding the lock.  Fix that here to be the pid of lockd.
> 
> Also, fix the client case so that the returned lock pid is negative, which
> indicates a remote lock on a remote file.

ACK.

Uh, I guess I'll take this if nobody else speaks up.

--b.

> 
> Fixes: 9d5b86ac13c5 ("fs/locks: Remove fl_nspid and use fs-specific...")
> Cc: stable@vger.kernel.org
> 
> Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
> ---
>  fs/lockd/clntproc.c | 2 +-
>  fs/lockd/xdr.c      | 4 ++--
>  fs/lockd/xdr4.c     | 4 ++--
>  3 files changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/lockd/clntproc.c b/fs/lockd/clntproc.c
> index d20b92f271c2..0a67dd4250e9 100644
> --- a/fs/lockd/clntproc.c
> +++ b/fs/lockd/clntproc.c
> @@ -442,7 +442,7 @@ nlmclnt_test(struct nlm_rqst *req, struct file_lock *fl)
>  			fl->fl_start = req->a_res.lock.fl.fl_start;
>  			fl->fl_end = req->a_res.lock.fl.fl_end;
>  			fl->fl_type = req->a_res.lock.fl.fl_type;
> -			fl->fl_pid = 0;
> +			fl->fl_pid = -req->a_res.lock.fl.fl_pid;
>  			break;
>  		default:
>  			status = nlm_stat_to_errno(req->a_res.status);
> diff --git a/fs/lockd/xdr.c b/fs/lockd/xdr.c
> index 7147e4aebecc..9846f7e95282 100644
> --- a/fs/lockd/xdr.c
> +++ b/fs/lockd/xdr.c
> @@ -127,7 +127,7 @@ nlm_decode_lock(__be32 *p, struct nlm_lock *lock)
>  
>  	locks_init_lock(fl);
>  	fl->fl_owner = current->files;
> -	fl->fl_pid   = (pid_t)lock->svid;
> +	fl->fl_pid   = current->tgid;
>  	fl->fl_flags = FL_POSIX;
>  	fl->fl_type  = F_RDLCK;		/* as good as anything else */
>  	start = ntohl(*p++);
> @@ -269,7 +269,7 @@ nlmsvc_decode_shareargs(struct svc_rqst *rqstp, __be32 *p)
>  	memset(lock, 0, sizeof(*lock));
>  	locks_init_lock(&lock->fl);
>  	lock->svid = ~(u32) 0;
> -	lock->fl.fl_pid = (pid_t)lock->svid;
> +	lock->fl.fl_pid = current->tgid;
>  
>  	if (!(p = nlm_decode_cookie(p, &argp->cookie))
>  	 || !(p = xdr_decode_string_inplace(p, &lock->caller,
> diff --git a/fs/lockd/xdr4.c b/fs/lockd/xdr4.c
> index 7ed9edf9aed4..70154f376695 100644
> --- a/fs/lockd/xdr4.c
> +++ b/fs/lockd/xdr4.c
> @@ -119,7 +119,7 @@ nlm4_decode_lock(__be32 *p, struct nlm_lock *lock)
>  
>  	locks_init_lock(fl);
>  	fl->fl_owner = current->files;
> -	fl->fl_pid   = (pid_t)lock->svid;
> +	fl->fl_pid   = current->tgid;
>  	fl->fl_flags = FL_POSIX;
>  	fl->fl_type  = F_RDLCK;		/* as good as anything else */
>  	p = xdr_decode_hyper(p, &start);
> @@ -266,7 +266,7 @@ nlm4svc_decode_shareargs(struct svc_rqst *rqstp, __be32 *p)
>  	memset(lock, 0, sizeof(*lock));
>  	locks_init_lock(&lock->fl);
>  	lock->svid = ~(u32) 0;
> -	lock->fl.fl_pid = (pid_t)lock->svid;
> +	lock->fl.fl_pid = current->tgid;
>  
>  	if (!(p = nlm4_decode_cookie(p, &argp->cookie))
>  	 || !(p = xdr_decode_string_inplace(p, &lock->caller,
> -- 
> 2.14.3