SUNRPC: Don't try to parse incomplete RPC messages

If the copy of the RPC reply into our buffers did not complete, and
we could end up with a truncated message. In that case, just resend
the call.

Fixes: a0584ee9ae ("SUNRPC: Use struct xdr_stream when decoding...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This commit is contained in:
Trond Myklebust 2019-09-16 09:12:19 -04:00 committed by Anna Schumaker
parent f925ab926d
commit 9ba828861c

View File

@ -2465,6 +2465,7 @@ call_decode(struct rpc_task *task)
struct rpc_clnt *clnt = task->tk_client; struct rpc_clnt *clnt = task->tk_client;
struct rpc_rqst *req = task->tk_rqstp; struct rpc_rqst *req = task->tk_rqstp;
struct xdr_stream xdr; struct xdr_stream xdr;
int err;
dprint_status(task); dprint_status(task);
@ -2487,6 +2488,15 @@ call_decode(struct rpc_task *task)
* before it changed req->rq_reply_bytes_recvd. * before it changed req->rq_reply_bytes_recvd.
*/ */
smp_rmb(); smp_rmb();
/*
* Did we ever call xprt_complete_rqst()? If not, we should assume
* the message is incomplete.
*/
err = -EAGAIN;
if (!req->rq_reply_bytes_recvd)
goto out;
req->rq_rcv_buf.len = req->rq_private_buf.len; req->rq_rcv_buf.len = req->rq_private_buf.len;
/* Check that the softirq receive buffer is valid */ /* Check that the softirq receive buffer is valid */
@ -2495,7 +2505,9 @@ call_decode(struct rpc_task *task)
xdr_init_decode(&xdr, &req->rq_rcv_buf, xdr_init_decode(&xdr, &req->rq_rcv_buf,
req->rq_rcv_buf.head[0].iov_base, req); req->rq_rcv_buf.head[0].iov_base, req);
switch (rpc_decode_header(task, &xdr)) { err = rpc_decode_header(task, &xdr);
out:
switch (err) {
case 0: case 0:
task->tk_action = rpc_exit_task; task->tk_action = rpc_exit_task;
task->tk_status = rpcauth_unwrap_resp(task, &xdr); task->tk_status = rpcauth_unwrap_resp(task, &xdr);