NLM/lockd: Ensure we don't corrupt fl->fl_flags in nlmclnt_unlock()

Also fix up nlmclnt_lock() so that it doesn't pass modified versions of
fl->fl_flags to nlmclnt_cancel() and other helpers.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 10 insertions, 6 deletions

diff --git a/fs/lockd/clntproc.c b/fs/lockd/clntproc.c
index b6b74a60e1eb..4e1c0123b45d 100644
--- a/fs/lockd/clntproc.c
+++ b/fs/lockd/clntproc.c
@@ -493,6 +493,7 @@ nlmclnt_lock(struct nlm_rqst *req, struct file_lock *fl)
         }
         fl->fl_flags |= FL_ACCESS;
         status = do_vfs_lock(fl);
+        fl->fl_flags = fl_flags;
         if (status < 0)
                 goto out;
 
@@ -530,10 +531,11 @@ again:
                         goto again;
                 }
                 /* Ensure the resulting lock will get added to granted list */
-                fl->fl_flags = fl_flags | FL_SLEEP;
+                fl->fl_flags |= FL_SLEEP;
                 if (do_vfs_lock(fl) < 0)
                         printk(KERN_WARNING "%s: VFS is out of sync with lock manager!\n", __FUNCTION__);
                 up_read(&host->h_rwsem);
+                fl->fl_flags = fl_flags;
         }
         status = nlm_stat_to_errno(resp->status);
 out_unblock:
@@ -543,7 +545,6 @@ out_unblock:
                 nlmclnt_cancel(host, req->a_args.block, fl);
 out:
         nlm_release_call(req);
-        fl->fl_flags = fl_flags;
         return status;
 }
 
@@ -598,7 +599,8 @@ nlmclnt_unlock(struct nlm_rqst *req, struct file_lock *fl)
 {
         struct nlm_host *host = req->a_host;
         struct nlm_res  *resp = &req->a_res;
-        int status = 0;
+        int status;
+        unsigned char fl_flags = fl->fl_flags;
 
         /*
          * Note: the server is supposed to either grant us the unlock
@@ -607,11 +609,13 @@ nlmclnt_unlock(struct nlm_rqst *req, struct file_lock *fl)
          */
         fl->fl_flags |= FL_EXISTS;
         down_read(&host->h_rwsem);
-        if (do_vfs_lock(fl) == -ENOENT) {
-                up_read(&host->h_rwsem);
+        status = do_vfs_lock(fl);
+        up_read(&host->h_rwsem);
+        fl->fl_flags = fl_flags;
+        if (status == -ENOENT) {
+                status = 0;
                 goto out;
         }
-        up_read(&host->h_rwsem);
 
         if (req->a_flags & RPC_TASK_ASYNC)
                 return nlm_async_call(req, NLMPROC_UNLOCK, &nlmclnt_unlock_ops);