From 38b7631fbe42e6e247e9fc9879f961b14a687e3b Mon Sep 17 00:00:00 2001
From: Benjamin Coddington <bcodding@redhat.com>
Date: Fri, 20 Nov 2015 09:55:30 -0500
Subject: nfs4: limit callback decoding to received bytes
A truncated cb_compound request will cause the client to decode null or
data from a previous callback for nfs4.1 backchannel case, or uninitialized
data for the nfs4.0 case. This is because the path through
svc_process_common() advances the request's iov_base and decrements iov_len
without adjusting the overall xdr_buf's len field. That causes
xdr_init_decode() to set up the xdr_stream with an incorrect length in
nfs4_callback_compound().
Fixing this for the nfs4.1 backchannel case first requires setting the
correct iov_len and page_len based on the length of received data in the
same manner as the nfs4.0 case.
Then the request's xdr_buf length can be adjusted for both cases based upon
the remaining iov_len and page_len.
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
---
net/sunrpc/svc.c | 1 +
1 file changed, 1 insertion(+)
(limited to 'net/sunrpc/svc.c')
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index bc5b7b5032ca..7fccf9675df8 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -1363,6 +1363,7 @@ bc_svc_process(struct svc_serv *serv, struct rpc_rqst *req,
memcpy(&rqstp->rq_addr, &req->rq_xprt->addr, rqstp->rq_addrlen);
memcpy(&rqstp->rq_arg, &req->rq_rcv_buf, sizeof(rqstp->rq_arg));
memcpy(&rqstp->rq_res, &req->rq_snd_buf, sizeof(rqstp->rq_res));
+ rqstp->rq_arg.len = req->rq_private_buf.len;
/* reset result send buffer "put" position */
resv->iov_len = 0;
--
cgit v1.2.1
From 756b9b37cfb2e3dc76b2e43a8c097402ac736e07 Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trond.myklebust@primarydata.com>
Date: Mon, 7 Dec 2015 12:52:23 -0800
Subject: SUNRPC: Fix callback channel
The NFSv4.1 callback channel is currently broken because the receive
message will keep shrinking because the backchannel receive buffer size
never gets reset.
The easiest solution to this problem is instead of changing the receive
buffer, to rather adjust the copied request.
Fixes: 38b7631fbe42 ("nfs4: limit callback decoding to received bytes")
Cc: Benjamin Coddington <bcodding@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
---
net/sunrpc/svc.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
(limited to 'net/sunrpc/svc.c')
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index 7fccf9675df8..cc9852897395 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -1363,7 +1363,19 @@ bc_svc_process(struct svc_serv *serv, struct rpc_rqst *req,
memcpy(&rqstp->rq_addr, &req->rq_xprt->addr, rqstp->rq_addrlen);
memcpy(&rqstp->rq_arg, &req->rq_rcv_buf, sizeof(rqstp->rq_arg));
memcpy(&rqstp->rq_res, &req->rq_snd_buf, sizeof(rqstp->rq_res));
+
+ /* Adjust the argument buffer length */
rqstp->rq_arg.len = req->rq_private_buf.len;
+ if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len) {
+ rqstp->rq_arg.head[0].iov_len = rqstp->rq_arg.len;
+ rqstp->rq_arg.page_len = 0;
+ } else if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len +
+ rqstp->rq_arg.page_len)
+ rqstp->rq_arg.page_len = rqstp->rq_arg.len -
+ rqstp->rq_arg.head[0].iov_len;
+ else
+ rqstp->rq_arg.len = rqstp->rq_arg.head[0].iov_len +
+ rqstp->rq_arg.page_len;
/* reset result send buffer "put" position */
resv->iov_len = 0;
--
cgit v1.2.1