From 910e425b29da7b601a99f49e81da666ab8ed5920 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Tue, 23 Oct 2012 17:50:07 -0400 Subject: SUNRPC: Prevent races in xs_abort_connection() commit 4bc1e68ed6a8b59be8a79eb719be515a55c7bc68 upstream. The call to xprt_disconnect_done() that is triggered by a successful connection reset will trigger another automatic wakeup of all tasks on the xprt->pending rpc_wait_queue. In particular it will cause an early wake up of the task that called xprt_connect(). All we really want to do here is clear all the socket-specific state flags, so we split that functionality out of xs_sock_mark_closed() into a helper that can be called by xs_abort_connection() Reported-by: Chris Perl Signed-off-by: Trond Myklebust Tested-by: Chris Perl Signed-off-by: Greg Kroah-Hartman --- net/sunrpc/xprtsock.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c index 2b17766..2202a14 100644 --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -1449,7 +1449,7 @@ static void xs_tcp_cancel_linger_timeout(struct rpc_xprt *xprt) xprt_clear_connecting(xprt); } -static void xs_sock_mark_closed(struct rpc_xprt *xprt) +static void xs_sock_reset_connection_flags(struct rpc_xprt *xprt) { smp_mb__before_clear_bit(); clear_bit(XPRT_CONNECTION_ABORT, &xprt->state); @@ -1457,6 +1457,11 @@ static void xs_sock_mark_closed(struct rpc_xprt *xprt) clear_bit(XPRT_CLOSE_WAIT, &xprt->state); clear_bit(XPRT_CLOSING, &xprt->state); smp_mb__after_clear_bit(); +} + +static void xs_sock_mark_closed(struct rpc_xprt *xprt) +{ + xs_sock_reset_connection_flags(xprt); /* Mark transport as closed and wake up all pending tasks */ xprt_disconnect_done(xprt); } @@ -1991,10 +1996,8 @@ static void xs_abort_connection(struct sock_xprt *transport) any.sa_family = AF_UNSPEC; result = kernel_connect(transport->sock, &any, sizeof(any), 0); if (!result) - xs_sock_mark_closed(&transport->xprt); - else - dprintk("RPC: AF_UNSPEC connect return code %d\n", - result); + xs_sock_reset_connection_flags(&transport->xprt); + dprintk("RPC: AF_UNSPEC connect return code %d\n", result); } static void xs_tcp_reuse_connection(struct sock_xprt *transport) -- cgit v1.1