From: Bryan Schumaker Date: Mon, 24 Sep 2012 13:39:01 -0400 Subject: SUNRPC: Set alloc_slot for backchannel tcp ops commit 84e28a307e376f271505af65a7b7e212dd6f61f4 upstream. f39c1bfb5a03e2d255451bff05be0d7255298fa4 (SUNRPC: Fix a UDP transport regression) introduced the "alloc_slot" function for xprt operations, but never created one for the backchannel operations. This patch fixes a null pointer dereference when mounting NFS over v4.1. Call Trace: [] ? xprt_reserve+0x47/0x50 [sunrpc] [] call_reserve+0x34/0x60 [sunrpc] [] __rpc_execute+0x90/0x400 [sunrpc] [] rpc_async_schedule+0x2a/0x40 [sunrpc] [] process_one_work+0x139/0x500 [] ? alloc_worker+0x70/0x70 [] ? __rpc_execute+0x400/0x400 [sunrpc] [] worker_thread+0x15e/0x460 [] ? preempt_schedule+0x49/0x70 [] ? rescuer_thread+0x230/0x230 [] kthread+0x93/0xa0 [] kernel_thread_helper+0x4/0x10 [] ? kthread_freezable_should_stop+0x70/0x70 [] ? gs_change+0x13/0x13 Signed-off-by: Bryan Schumaker Signed-off-by: Trond Myklebust [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- net/sunrpc/xprtsock.c | 1 + 1 file changed, 1 insertion(+) --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -2488,6 +2488,7 @@ static struct rpc_xprt_ops xs_tcp_ops = static struct rpc_xprt_ops bc_tcp_ops = { .reserve_xprt = xprt_reserve_xprt, .release_xprt = xprt_release_xprt, + .alloc_slot = xprt_alloc_slot, .buf_alloc = bc_malloc, .buf_free = bc_free, .send_request = bc_send_request,