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auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dm-devel-bounces@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com From: Martin Wilck The unix socket listener thread doesn't even look at the revents returned by poll() while the daemon is configuring. This may cause a closed client socket to be kept open for a long time by the server, while the listener basically performs a busy loop, as ppoll() always returns immediately as long as the POLLHUP condition exists. Worse, it can happen that multipathd reads data from such a closed client socket after the client has disconnected. See the description of POLLHUP in poll(2). Close connections immediately if HUP is received. Also, use the fd in log messages to identify the client rather than the random index. Reviewed-by: Benjamin Marzinski Signed-off-by: Martin Wilck --- multipathd/uxlsnr.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/multipathd/uxlsnr.c b/multipathd/uxlsnr.c index 20efbd3..7e88538 100644 --- a/multipathd/uxlsnr.c +++ b/multipathd/uxlsnr.c @@ -393,7 +393,7 @@ void * uxsock_listen(uxsock_trigger_fn uxsock_trigger, long ux_sock, /* see if a client wants to speak to us */ for (i = POLLFDS_BASE; i < n_pfds; i++) { - if (polls[i].revents & POLLIN) { + if (polls[i].revents & (POLLIN|POLLHUP|POLLERR)) { struct timespec start_time; c = NULL; @@ -410,6 +410,12 @@ void * uxsock_listen(uxsock_trigger_fn uxsock_trigger, long ux_sock, i, polls[i].fd); continue; } + if (polls[i].revents & (POLLHUP|POLLERR)) { + condlog(4, "cli[%d]: Disconnected", + c->fd); + dead_client(c); + continue; + } get_monotonic_time(&start_time); if (recv_packet_from_client(c->fd, &inbuf, uxsock_timeout) @@ -423,7 +429,7 @@ void * uxsock_listen(uxsock_trigger_fn uxsock_trigger, long ux_sock, continue; } condlog(4, "cli[%d]: Got request [%s]", - i, inbuf); + polls[i].fd, inbuf); uxsock_trigger(inbuf, &reply, &rlen, _socket_client_is_root(c->fd), trigger_data); @@ -434,7 +440,7 @@ void * uxsock_listen(uxsock_trigger_fn uxsock_trigger, long ux_sock, } else { condlog(4, "cli[%d]: " "Reply [%d bytes]", - i, rlen); + polls[i].fd, rlen); } FREE(reply); reply = NULL;