SUNRPC: stop printk reading past end of string

stable inclusion
from linux-4.19.147
commit 61279a7b3e337b8c8605987591964db4a2b3eb91

--------------------------------

[ Upstream commit 8c6b6c79 ]

Since p points at raw xdr data, there's no guarantee that it's NULL
terminated, so we should give a length.  And probably escape any special
characters too.
Reported-by: NZhi Li <yieli@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
Signed-off-by: NAichun Li <liaichun@huawei.com>
Reviewed-by: Nwangxiaopeng <wangxiaopeng7@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

net/sunrpc/rpcb_clnt.c

@@ -981,8 +981,8 @@ static int rpcb_dec_getaddr(struct rpc_rqst *req, struct xdr_stream *xdr,
 	p = xdr_inline_decode(xdr, len);
 	if (unlikely(p == NULL))
 		goto out_fail;
-	dprintk("RPC: %5u RPCB_%s reply: %s\n", req->rq_task->tk_pid,
-			req->rq_task->tk_msg.rpc_proc->p_name, (char *)p);
+	dprintk("RPC: %5u RPCB_%s reply: %*pE\n", req->rq_task->tk_pid,
+			req->rq_task->tk_msg.rpc_proc->p_name, len, (char *)p);
 
 	if (rpc_uaddr2sockaddr(req->rq_xprt->xprt_net, (char *)p, len,
 				sap, sizeof(address)) == 0)