NFS: Move the flock open mode check into nfs_flock()

We only need to check lock exclusive/shared types against open mode when
flock() is used on NFS, so move it into the flock-specific path instead of
checking it for all locks.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index 668213984d68708c3d54cccce36ad3a0c048657e..b7f4af3483b6a311ccf4724b53370d28744135d5 100644 (file)
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -820,9 +820,23 @@ int nfs_flock(struct file *filp, int cmd, struct file_lock *fl)
        if (NFS_SERVER(inode)->flags & NFS_MOUNT_LOCAL_FLOCK)
                is_local = 1;
 
-       /* We're simulating flock() locks using posix locks on the server */
-       if (fl->fl_type == F_UNLCK)
+       /*
+        * VFS doesn't require the open mode to match a flock() lock's type.
+        * NFS, however, may simulate flock() locking with posix locking which
+        * requires the open mode to match the lock type.
+        */
+       switch (fl->fl_type) {
+       case F_UNLCK:
                return do_unlk(filp, cmd, fl, is_local);
+       case F_RDLCK:
+               if (!(filp->f_mode & FMODE_READ))
+                       return -EBADF;
+               break;
+       case F_WRLCK:
+               if (!(filp->f_mode & FMODE_WRITE))
+                       return -EBADF;
+       }
+
        return do_setlk(filp, cmd, fl, is_local);
 }
 EXPORT_SYMBOL_GPL(nfs_flock);

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index d682ef3b2da260d06468229046c3e0b233a1ec17..c52f72c86940f7729d1d322ea349e47585f1d53c 100644 (file)
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -6469,20 +6469,6 @@ nfs4_proc_lock(struct file *filp, int cmd, struct file_lock *request)
            !test_bit(NFS_STATE_POSIX_LOCKS, &state->flags))
                return -ENOLCK;
 
-       /*
-        * Don't rely on the VFS having checked the file open mode,
-        * since it won't do this for flock() locks.
-        */
-       switch (request->fl_type) {
-       case F_RDLCK:
-               if (!(filp->f_mode & FMODE_READ))
-                       return -EBADF;
-               break;
-       case F_WRLCK:
-               if (!(filp->f_mode & FMODE_WRITE))
-                       return -EBADF;
-       }
-
        status = nfs4_set_lock_state(state, request);
        if (status != 0)
                return status;