lkml.org 
[lkml]   [2022]   [Apr]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH net] SUNRPC: Fix local socket leak in xs_local_setup_socket()
Date
If the connection to a local endpoint in xs_local_setup_socket() fails,
fput() is missing in the error path, which will result in a socket leak.
It can be reproduced in simple script below.

while true
do
systemctl stop rpcbind.service
systemctl stop rpc-statd.service
systemctl stop nfs-server.service

systemctl restart rpcbind.service
systemctl restart rpc-statd.service
systemctl restart nfs-server.service
done

When executing the script, you can observe that the
"cat /proc/net/unix | wc -l" count keeps growing.

Add the missing fput(), and restore transport to old socket.

Signed-off-by: Wang Hai <wanghai38@huawei.com>
---
net/sunrpc/xprtsock.c | 20 ++++++++++++++++++--
1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index 0f39e08ee580..7219c545385e 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -1819,6 +1819,9 @@ static int xs_local_finish_connecting(struct rpc_xprt *xprt,
{
struct sock_xprt *transport = container_of(xprt, struct sock_xprt,
xprt);
+ struct socket *trans_sock = NULL;
+ struct sock *trans_inet = NULL;
+ int ret;

if (!transport->inet) {
struct sock *sk = sock->sk;
@@ -1835,6 +1838,9 @@ static int xs_local_finish_connecting(struct rpc_xprt *xprt,

xprt_clear_connected(xprt);

+ trans_sock = transport->sock;
+ trans_inet = transport->inet;
+
/* Reset to new socket */
transport->sock = sock;
transport->inet = sk;
@@ -1844,7 +1850,14 @@ static int xs_local_finish_connecting(struct rpc_xprt *xprt,

xs_stream_start_connect(transport);

- return kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
+ ret = kernel_connect(sock, xs_addr(xprt), xprt->addrlen, 0);
+ /* Restore to old socket */
+ if (ret && trans_inet) {
+ transport->sock = trans_sock;
+ transport->inet = trans_inet;
+ }
+
+ return ret;
}

/**
@@ -1887,7 +1900,7 @@ static int xs_local_setup_socket(struct sock_xprt *transport)
xprt->stat.connect_time += (long)jiffies -
xprt->stat.connect_start;
xprt_set_connected(xprt);
- break;
+ goto out;
case -ENOBUFS:
break;
case -ENOENT:
@@ -1904,6 +1917,9 @@ static int xs_local_setup_socket(struct sock_xprt *transport)
xprt->address_strings[RPC_DISPLAY_ADDR]);
}

+ transport->file = NULL;
+ fput(filp);
+
out:
xprt_clear_connecting(xprt);
xprt_wake_pending_tasks(xprt, status);
--
2.17.1
\
 
 \ /
  Last update: 2022-04-26 15:02    [W:0.069 / U:0.232 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site