From 9734ad57b0f1a367fd3a00d717f97f8c00d9edb7 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Fri, 15 Mar 2019 12:47:34 -0400 Subject: SUNRPC: Fix a client regression when handling oversized replies If the server sends a reply that is larger than the pre-allocated buffer, then the current code may fail to register how much of the stream that it has finished reading. This again can lead to hangs. Fixes: e92053a52e68 ("SUNRPC: Handle zero length fragments correctly") Signed-off-by: Trond Myklebust --- net/sunrpc/xprtsock.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net') diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c index 42f45d33dc56..9359539907ba 100644 --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -453,7 +453,7 @@ xs_read_xdr_buf(struct socket *sock, struct msghdr *msg, int flags, goto out; if (ret != want) goto out; - } else + } else if (offset < seek_init) offset = seek_init; ret = -EMSGSIZE; out: -- cgit v1.2.3 From 513149607d19bc3821386fb5ac75f8b99fd4b115 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Fri, 15 Mar 2019 12:55:59 -0400 Subject: SUNRPC: Fix the minimal size for reply buffer allocation We must at minimum allocate enough memory to be able to see any auth errors in the reply from the server. Fixes: 2c94b8eca1a26 ("SUNRPC: Use au_rslack when computing reply...") Signed-off-by: Trond Myklebust --- net/sunrpc/clnt.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'net') diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c index 4216fe33204a..310873895578 100644 --- a/net/sunrpc/clnt.c +++ b/net/sunrpc/clnt.c @@ -1730,7 +1730,12 @@ call_allocate(struct rpc_task *task) req->rq_callsize = RPC_CALLHDRSIZE + (auth->au_cslack << 1) + proc->p_arglen; req->rq_callsize <<= 2; - req->rq_rcvsize = RPC_REPHDRSIZE + auth->au_rslack + proc->p_replen; + /* + * Note: the reply buffer must at minimum allocate enough space + * for the 'struct accepted_reply' from RFC5531. + */ + req->rq_rcvsize = RPC_REPHDRSIZE + auth->au_rslack + \ + max_t(size_t, proc->p_replen, 2); req->rq_rcvsize <<= 2; status = xprt->ops->buf_alloc(task); -- cgit v1.2.3 From 27adc785928ae6b34cdda96f472735b77c91e247 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Fri, 15 Mar 2019 08:01:16 -0400 Subject: SUNRPC: Use the ENOTCONN error on socket disconnect When the socket is closed, we currently send an EAGAIN error to all pending requests in order to ask them to retransmit. Use ENOTCONN instead, to ensure that they try to reconnect before attempting to transmit. This also helps SOFTCONN tasks to behave correctly in this situation. Signed-off-by: Trond Myklebust --- net/sunrpc/xprt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net') diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c index e096c5a725df..d7117d241460 100644 --- a/net/sunrpc/xprt.c +++ b/net/sunrpc/xprt.c @@ -664,7 +664,7 @@ void xprt_disconnect_done(struct rpc_xprt *xprt) spin_lock_bh(&xprt->transport_lock); xprt_clear_connected(xprt); xprt_clear_write_space_locked(xprt); - xprt_wake_pending_tasks(xprt, -EAGAIN); + xprt_wake_pending_tasks(xprt, -ENOTCONN); spin_unlock_bh(&xprt->transport_lock); } EXPORT_SYMBOL_GPL(xprt_disconnect_done); -- cgit v1.2.3 From eb90a16e9087063943859ae99bbdddd1fbfcf477 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Fri, 15 Mar 2019 09:29:00 -0400 Subject: SUNRPC: rpc_decode_header() must always return a non-zero value on error Ensure that when the "garbage args" case falls through, we do set an error of EIO. Fixes: a0584ee9aed8 ("SUNRPC: Use struct xdr_stream when decoding...") Signed-off-by: Trond Myklebust --- net/sunrpc/clnt.c | 20 +++++++------------- 1 file changed, 7 insertions(+), 13 deletions(-) (limited to 'net') diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c index 310873895578..1f47801e0002 100644 --- a/net/sunrpc/clnt.c +++ b/net/sunrpc/clnt.c @@ -2454,7 +2454,7 @@ static noinline int rpc_decode_header(struct rpc_task *task, struct xdr_stream *xdr) { struct rpc_clnt *clnt = task->tk_client; - int error = -EACCES; + int error; __be32 *p; /* RFC-1014 says that the representation of XDR data must be a @@ -2463,7 +2463,7 @@ rpc_decode_header(struct rpc_task *task, struct xdr_stream *xdr) * undefined results */ if (task->tk_rqstp->rq_rcv_buf.len & 3) - goto out_badlen; + goto out_unparsable; p = xdr_inline_decode(xdr, 3 * sizeof(*p)); if (!p) @@ -2498,9 +2498,10 @@ rpc_decode_header(struct rpc_task *task, struct xdr_stream *xdr) goto out_err; case rpc_garbage_args: trace_rpc__garbage_args(task); + error = -EIO; break; default: - trace_rpc__unparsable(task); + goto out_unparsable; } out_garbage: @@ -2514,11 +2515,6 @@ out_err: rpc_exit(task, error); return error; -out_badlen: - trace_rpc__unparsable(task); - error = -EIO; - goto out_err; - out_unparsable: trace_rpc__unparsable(task); error = -EIO; @@ -2529,6 +2525,7 @@ out_verifier: goto out_garbage; out_msg_denied: + error = -EACCES; p = xdr_inline_decode(xdr, sizeof(*p)); if (!p) goto out_unparsable; @@ -2540,9 +2537,7 @@ out_msg_denied: error = -EPROTONOSUPPORT; goto out_err; default: - trace_rpc__unparsable(task); - error = -EIO; - goto out_err; + goto out_unparsable; } p = xdr_inline_decode(xdr, sizeof(*p)); @@ -2577,8 +2572,7 @@ out_msg_denied: task->tk_xprt->servername); break; default: - trace_rpc__unparsable(task); - error = -EIO; + goto out_unparsable; } goto out_err; } -- cgit v1.2.3 From 928d42f7d8737e1d6327e09668525f59725dabf9 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Fri, 15 Mar 2019 10:12:30 -0400 Subject: SUNRPC: Handle the SYSTEM_ERR rpc error Handle the SYSTEM_ERR rpc error by retrying the RPC call as if it were a garbage argument. Signed-off-by: Trond Myklebust --- net/sunrpc/clnt.c | 1 + 1 file changed, 1 insertion(+) (limited to 'net') diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c index 1f47801e0002..cb73d6c25857 100644 --- a/net/sunrpc/clnt.c +++ b/net/sunrpc/clnt.c @@ -2497,6 +2497,7 @@ rpc_decode_header(struct rpc_task *task, struct xdr_stream *xdr) error = -EOPNOTSUPP; goto out_err; case rpc_garbage_args: + case rpc_system_err: trace_rpc__garbage_args(task); error = -EIO; break; -- cgit v1.2.3 From 5e3863fd597eba8c6679de805681631b1aad9bdb Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Fri, 15 Mar 2019 13:11:36 -0400 Subject: SUNRPC: Remove redundant check for the reply length in call_decode() Now that we're using the xdr_stream functions to decode the header, the test for the minimum reply length is redundant. Signed-off-by: Trond Myklebust --- net/sunrpc/clnt.c | 4 ---- 1 file changed, 4 deletions(-) (limited to 'net') diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c index cb73d6c25857..228970e6e52b 100644 --- a/net/sunrpc/clnt.c +++ b/net/sunrpc/clnt.c @@ -2392,9 +2392,6 @@ call_decode(struct rpc_task *task) WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf, sizeof(req->rq_rcv_buf)) != 0); - if (req->rq_rcv_buf.len < 12) - goto out_retry; - xdr_init_decode(&xdr, &req->rq_rcv_buf, req->rq_rcv_buf.head[0].iov_base, req); switch (rpc_decode_header(task, &xdr)) { @@ -2405,7 +2402,6 @@ call_decode(struct rpc_task *task) task->tk_pid, __func__, task->tk_status); return; case -EAGAIN: -out_retry: task->tk_status = 0; /* Note: rpc_decode_header() may have freed the RPC slot */ if (task->tk_rqstp == req) { -- cgit v1.2.3