From: Chuck Lever chuck.lever@oracle.com
commit 23cf1ee1f1869966b75518c59b5cbda4c6c92450 upstream.
Utilize the xpo_release_rqst transport method to ensure that each rqstp's svc_rdma_recv_ctxt object is released even when the server cannot return a Reply for that rqstp.
Without this fix, each RPC whose Reply cannot be sent leaks one svc_rdma_recv_ctxt. This is a 2.5KB structure, a 4KB DMA-mapped Receive buffer, and any pages that might be part of the Reply message.
The leak is infrequent unless the network fabric is unreliable or Kerberos is in use, as GSS sequence window overruns, which result in connection loss, are more common on fast transports.
Fixes: 3a88092ee319 ("svcrdma: Preserve Receive buffer until svc_rdma_sendto") Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- include/linux/sunrpc/svc_rdma.h | 1 + net/sunrpc/svc_xprt.c | 3 --- net/sunrpc/svcsock.c | 4 ++++ net/sunrpc/xprtrdma/svc_rdma_recvfrom.c | 22 ++++++++++++++++++++++ net/sunrpc/xprtrdma/svc_rdma_sendto.c | 13 +++---------- net/sunrpc/xprtrdma/svc_rdma_transport.c | 5 ----- 6 files changed, 30 insertions(+), 18 deletions(-)
diff --git a/include/linux/sunrpc/svc_rdma.h b/include/linux/sunrpc/svc_rdma.h index fd78f78..3e3214c 100644 --- a/include/linux/sunrpc/svc_rdma.h +++ b/include/linux/sunrpc/svc_rdma.h @@ -159,6 +159,7 @@ extern int svc_rdma_handle_bc_reply(struct rpc_xprt *xprt, extern void svc_rdma_recv_ctxt_put(struct svcxprt_rdma *rdma, struct svc_rdma_recv_ctxt *ctxt); extern void svc_rdma_flush_recv_queues(struct svcxprt_rdma *rdma); +extern void svc_rdma_release_rqst(struct svc_rqst *rqstp); extern int svc_rdma_recvfrom(struct svc_rqst *);
/* svc_rdma_rw.c */ diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c index cde15c3..cf9ab05 100644 --- a/net/sunrpc/svc_xprt.c +++ b/net/sunrpc/svc_xprt.c @@ -878,9 +878,6 @@ int svc_send(struct svc_rqst *rqstp) if (!xprt) goto out;
- /* release the receive skb before sending the reply */ - xprt->xpt_ops->xpo_release_rqst(rqstp); - /* calculate over-all length */ xb = &rqstp->rq_res; xb->len = xb->head[0].iov_len + diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c index 8566531..d0b5a1c 100644 --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -636,6 +636,8 @@ static int svc_udp_recvfrom(struct svc_rqst *rqstp) { int error;
+ svc_release_udp_skb(rqstp); + error = svc_sendto(rqstp, &rqstp->rq_res); if (error == -ECONNREFUSED) /* ICMP error on earlier request. */ @@ -1173,6 +1175,8 @@ static int svc_tcp_sendto(struct svc_rqst *rqstp) int sent; __be32 reclen;
+ svc_release_skb(rqstp); + /* Set up the first element of the reply kvec. * Any other kvecs that may be in use have been taken * care of by the server implementation itself. diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c index b24d5b8..16c8174 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c +++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c @@ -226,6 +226,26 @@ void svc_rdma_recv_ctxt_put(struct svcxprt_rdma *rdma, svc_rdma_recv_ctxt_destroy(rdma, ctxt); }
+/** + * svc_rdma_release_rqst - Release transport-specific per-rqst resources + * @rqstp: svc_rqst being released + * + * Ensure that the recv_ctxt is released whether or not a Reply + * was sent. For example, the client could close the connection, + * or svc_process could drop an RPC, before the Reply is sent. + */ +void svc_rdma_release_rqst(struct svc_rqst *rqstp) +{ + struct svc_rdma_recv_ctxt *ctxt = rqstp->rq_xprt_ctxt; + struct svc_xprt *xprt = rqstp->rq_xprt; + struct svcxprt_rdma *rdma = + container_of(xprt, struct svcxprt_rdma, sc_xprt); + + rqstp->rq_xprt_ctxt = NULL; + if (ctxt) + svc_rdma_recv_ctxt_put(rdma, ctxt); +} + static int __svc_rdma_post_recv(struct svcxprt_rdma *rdma, struct svc_rdma_recv_ctxt *ctxt) { @@ -704,6 +724,8 @@ int svc_rdma_recvfrom(struct svc_rqst *rqstp) __be32 *p; int ret;
+ rqstp->rq_xprt_ctxt = NULL; + spin_lock(&rdma_xprt->sc_rq_dto_lock); ctxt = svc_rdma_next_recv_ctxt(&rdma_xprt->sc_read_complete_q); if (ctxt) { diff --git a/net/sunrpc/xprtrdma/svc_rdma_sendto.c b/net/sunrpc/xprtrdma/svc_rdma_sendto.c index 840bd35..aa4d19a 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_sendto.c +++ b/net/sunrpc/xprtrdma/svc_rdma_sendto.c @@ -908,12 +908,7 @@ int svc_rdma_sendto(struct svc_rqst *rqstp) wr_lst, rp_ch); if (ret < 0) goto err1; - ret = 0; - -out: - rqstp->rq_xprt_ctxt = NULL; - svc_rdma_recv_ctxt_put(rdma, rctxt); - return ret; + return 0;
err2: if (ret != -E2BIG && ret != -EINVAL) @@ -922,14 +917,12 @@ int svc_rdma_sendto(struct svc_rqst *rqstp) ret = svc_rdma_send_error_msg(rdma, sctxt, rqstp); if (ret < 0) goto err1; - ret = 0; - goto out; + return 0;
err1: svc_rdma_send_ctxt_put(rdma, sctxt); err0: trace_svcrdma_send_failed(rqstp, ret); set_bit(XPT_CLOSE, &xprt->xpt_flags); - ret = -ENOTCONN; - goto out; + return -ENOTCONN; } diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c index 7308992..f182430 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_transport.c +++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c @@ -71,7 +71,6 @@ static struct svc_xprt *svc_rdma_create(struct svc_serv *serv, struct sockaddr *sa, int salen, int flags); static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt); -static void svc_rdma_release_rqst(struct svc_rqst *); static void svc_rdma_detach(struct svc_xprt *xprt); static void svc_rdma_free(struct svc_xprt *xprt); static int svc_rdma_has_wspace(struct svc_xprt *xprt); @@ -616,10 +615,6 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) return NULL; }
-static void svc_rdma_release_rqst(struct svc_rqst *rqstp) -{ -} - /* * When connected, an svc_xprt has at least two references: *