From f06f00a24d76e168ecb38d352126fd203937b601 Mon Sep 17 00:00:00 2001 From: "J. Bruce Fields" <bfields@redhat.com> Date: Mon, 20 Aug 2012 16:04:40 -0400 Subject: [PATCH] svcrpc: sends on closed socket should stop immediately svc_tcp_sendto sets XPT_CLOSE if we fail to transmit the entire reply. However, the XPT_CLOSE won't be acted on immediately. Meanwhile other threads could send further replies before the socket is really shut down. This can manifest as data corruption: for example, if a truncated read reply is followed by another rpc reply, that second reply will look to the client like further read data. Symptoms were data corruption preceded by svc_tcp_sendto logging something like kernel: rpc-srv/tcp: nfsd: sent only 963696 when sending 1048708 bytes - shutting down socket Cc: stable@vger.kernel.org Reported-by: Malahal Naineni <malahal@us.ibm.com> Tested-by: Malahal Naineni <malahal@us.ibm.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> --- net/sunrpc/svc_xprt.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c index 88f2bf671960..0d693a89434f 100644 --- a/net/sunrpc/svc_xprt.c +++ b/net/sunrpc/svc_xprt.c @@ -794,7 +794,8 @@ int svc_send(struct svc_rqst *rqstp) /* Grab mutex to serialize outgoing data. */ mutex_lock(&xprt->xpt_mutex); - if (test_bit(XPT_DEAD, &xprt->xpt_flags)) + if (test_bit(XPT_DEAD, &xprt->xpt_flags) + || test_bit(XPT_CLOSE, &xprt->xpt_flags)) len = -ENOTCONN; else len = xprt->xpt_ops->xpo_sendto(rqstp);