From 1310051c720a83c5717658bcbff710b260f2bff9 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Wed, 19 Jun 2019 10:32:43 -0400 Subject: xprtrdma: Replace use of xdr_stream_pos in rpcrdma_marshal_req This is a latent bug. xdr_stream_pos works by subtracting xdr_stream::nwords from xdr_buf::len. But xdr_stream::nwords is not initialized by xdr_init_encode(). It works today only because all fields in rpcrdma_req::rl_stream are initialized to zero by rpcrdma_req_create, making the subtraction in xdr_stream_pos always a no-op. I found this issue via code inspection. It was introduced by commit 39f4cd9e9982 ("xprtrdma: Harden chunk list encoding against send buffer overflow"), but the code has changed enough since then that this fix can't be automatically applied to stable. Signed-off-by: Chuck Lever Signed-off-by: Anna Schumaker --- include/trace/events/rpcrdma.h | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'include/trace') diff --git a/include/trace/events/rpcrdma.h b/include/trace/events/rpcrdma.h index f0678e3ac2d4..59492a93fe1d 100644 --- a/include/trace/events/rpcrdma.h +++ b/include/trace/events/rpcrdma.h @@ -470,13 +470,12 @@ TRACE_DEFINE_ENUM(rpcrdma_replych); TRACE_EVENT(xprtrdma_marshal, TP_PROTO( - const struct rpc_rqst *rqst, - unsigned int hdrlen, + const struct rpcrdma_req *req, unsigned int rtype, unsigned int wtype ), - TP_ARGS(rqst, hdrlen, rtype, wtype), + TP_ARGS(req, rtype, wtype), TP_STRUCT__entry( __field(unsigned int, task_id) @@ -491,10 +490,12 @@ TRACE_EVENT(xprtrdma_marshal, ), TP_fast_assign( + const struct rpc_rqst *rqst = &req->rl_slot; + __entry->task_id = rqst->rq_task->tk_pid; __entry->client_id = rqst->rq_task->tk_client->cl_clid; __entry->xid = be32_to_cpu(rqst->rq_xid); - __entry->hdrlen = hdrlen; + __entry->hdrlen = req->rl_hdrbuf.len; __entry->headlen = rqst->rq_snd_buf.head[0].iov_len; __entry->pagelen = rqst->rq_snd_buf.page_len; __entry->taillen = rqst->rq_snd_buf.tail[0].iov_len; -- cgit v1.2.3-55-g7522