From: Trond Myklebust Date: Wed, 31 Aug 2022 21:28:13 +0000 (-0400) Subject: SUNRPC: Fix call completion races with call_decode() X-Git-Tag: v6.0-rc6~12^2~3 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=17814819ac9829a437e06fbb5c7056a1f4f893da;p=thirdparty%2Fkernel%2Fstable.git SUNRPC: Fix call completion races with call_decode() We need to make sure that the req->rq_private_buf is completely up to date before we make req->rq_reply_bytes_recvd visible to the call_decode() routine in order to avoid triggering the WARN_ON(). Reported-by: Benjamin Coddington Fixes: 72691a269f0b ("SUNRPC: Don't reuse bvec on retransmission of the request") Tested-by: Benjamin Coddington Signed-off-by: Trond Myklebust --- diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c index d71eec494826b..f8fae78156494 100644 --- a/net/sunrpc/xprt.c +++ b/net/sunrpc/xprt.c @@ -1179,11 +1179,8 @@ xprt_request_dequeue_receive_locked(struct rpc_task *task) { struct rpc_rqst *req = task->tk_rqstp; - if (test_and_clear_bit(RPC_TASK_NEED_RECV, &task->tk_runstate)) { + if (test_and_clear_bit(RPC_TASK_NEED_RECV, &task->tk_runstate)) xprt_request_rb_remove(req->rq_xprt, req); - xdr_free_bvec(&req->rq_rcv_buf); - req->rq_private_buf.bvec = NULL; - } } /** @@ -1221,6 +1218,8 @@ void xprt_complete_rqst(struct rpc_task *task, int copied) xprt->stat.recvs++; + xdr_free_bvec(&req->rq_rcv_buf); + req->rq_private_buf.bvec = NULL; req->rq_private_buf.len = copied; /* Ensure all writes are done before we update */ /* req->rq_reply_bytes_recvd */ @@ -1453,6 +1452,7 @@ xprt_request_dequeue_xprt(struct rpc_task *task) xprt_request_dequeue_transmit_locked(task); xprt_request_dequeue_receive_locked(task); spin_unlock(&xprt->queue_lock); + xdr_free_bvec(&req->rq_rcv_buf); } }