From: Trond Myklebust Date: Tue, 23 Oct 2012 21:50:07 +0000 (-0400) Subject: SUNRPC: Prevent races in xs_abort_connection() X-Git-Tag: v3.6.5~83 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=eeaeb30f888f0872c029b441a69d67f43e712c80;p=thirdparty%2Fkernel%2Fstable.git 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 --- diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c index 094afc0703130..6a70db45c5b14 100644 --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -1459,7 +1459,7 @@ 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); @@ -1467,6 +1467,11 @@ 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); } @@ -2042,10 +2047,8 @@ 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)