NFSv4: rpc_mkpipe creating socket inodes w/out sk buffers

This patch stop rpc_mkpipe from create S_IFSOCK nodes what don't
have associated sk buffers attached (which causes SELinux to oops
during NFSv4 mounts). Instead the S_IFIFO mode bit is set which
probably make more sense and seems to work just fine during
my connectathon and fsx testing...

Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

net/sunrpc/rpc_pipe.c

@@ -720,7 +720,7 @@ rpc_mkpipe(struct dentry *parent, const char *name, void *private, struct rpc_pi
 	if (IS_ERR(dentry))
 		return dentry;
 	dir = parent->d_inode;
-	inode = rpc_get_inode(dir->i_sb, S_IFSOCK | S_IRUSR | S_IWUSR);
+	inode = rpc_get_inode(dir->i_sb, S_IFIFO | S_IRUSR | S_IWUSR);
 	if (!inode)
 		goto err_dput;
 	inode->i_ino = iunique(dir->i_sb, 100);