[PATCH 5.1 28/55] SUNRPC: Fix up calculation of client message length

From: Greg Kroah-Hartman
Date: Tue Jul 02 2019 - 04:03:51 EST


From: Trond Myklebust <trondmy@xxxxxxxxx>

commit 7e3d3620974b743b91b1f9d0660061b1de20174c upstream.

In the case where a record marker was used, xs_sendpages() needs
to return the length of the payload + record marker so that we
operate correctly in the case of a partial transmission.
When the callers check return value, they therefore need to
take into account the record marker length.

Fixes: 06b5fc3ad94e ("Merge tag 'nfs-rdma-for-5.1-1'...")
Cc: stable@xxxxxxxxxxxxxxx # 5.1+
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Signed-off-by: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
net/sunrpc/xprtsock.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)

--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -950,6 +950,8 @@ static int xs_local_send_request(struct
struct sock_xprt *transport =
container_of(xprt, struct sock_xprt, xprt);
struct xdr_buf *xdr = &req->rq_snd_buf;
+ rpc_fraghdr rm = xs_stream_record_marker(xdr);
+ unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
int status;
int sent = 0;

@@ -964,9 +966,7 @@ static int xs_local_send_request(struct

req->rq_xtime = ktime_get();
status = xs_sendpages(transport->sock, NULL, 0, xdr,
- transport->xmit.offset,
- xs_stream_record_marker(xdr),
- &sent);
+ transport->xmit.offset, rm, &sent);
dprintk("RPC: %s(%u) = %d\n",
__func__, xdr->len - transport->xmit.offset, status);

@@ -976,7 +976,7 @@ static int xs_local_send_request(struct
if (likely(sent > 0) || status == 0) {
transport->xmit.offset += sent;
req->rq_bytes_sent = transport->xmit.offset;
- if (likely(req->rq_bytes_sent >= req->rq_slen)) {
+ if (likely(req->rq_bytes_sent >= msglen)) {
req->rq_xmit_bytes_sent += transport->xmit.offset;
transport->xmit.offset = 0;
return 0;
@@ -1097,6 +1097,8 @@ static int xs_tcp_send_request(struct rp
struct rpc_xprt *xprt = req->rq_xprt;
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
struct xdr_buf *xdr = &req->rq_snd_buf;
+ rpc_fraghdr rm = xs_stream_record_marker(xdr);
+ unsigned int msglen = rm ? req->rq_slen + sizeof(rm) : req->rq_slen;
bool vm_wait = false;
int status;
int sent;
@@ -1122,9 +1124,7 @@ static int xs_tcp_send_request(struct rp
while (1) {
sent = 0;
status = xs_sendpages(transport->sock, NULL, 0, xdr,
- transport->xmit.offset,
- xs_stream_record_marker(xdr),
- &sent);
+ transport->xmit.offset, rm, &sent);

dprintk("RPC: xs_tcp_send_request(%u) = %d\n",
xdr->len - transport->xmit.offset, status);
@@ -1133,7 +1133,7 @@ static int xs_tcp_send_request(struct rp
* reset the count of bytes sent. */
transport->xmit.offset += sent;
req->rq_bytes_sent = transport->xmit.offset;
- if (likely(req->rq_bytes_sent >= req->rq_slen)) {
+ if (likely(req->rq_bytes_sent >= msglen)) {
req->rq_xmit_bytes_sent += transport->xmit.offset;
transport->xmit.offset = 0;
return 0;