From 4489d177ba3f6696982895676451e4a1c0d5cadc Mon Sep 17 00:00:00 2001 From: Luiz Otavio O souza Date: Fri, 21 Jul 2017 02:00:48 -0300 Subject: [PATCH] Do not allow the use of the loopback interface in netmap. The generic support in netmap send the packets using if_transmit() and the loopback do not support packets coming from if_transmit()/if_start(). This avoids the use of the loopback interface and the subsequent crash that happens when the application send packets to the loopback interface. Details in: https://github.com/luigirizzo/netmap/issues/322 Obtained from: FreeBSD --- sys/dev/netmap/netmap_generic.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/sys/dev/netmap/netmap_generic.c b/sys/dev/netmap/netmap_generic.c index 2e92f9b69..778e09697 100644 --- a/sys/dev/netmap/netmap_generic.c +++ b/sys/dev/netmap/netmap_generic.c @@ -75,6 +75,7 @@ __FBSDID("$FreeBSD: head/sys/dev/netmap/netmap_generic.c 274353 2014-11-10 20:19 #include /* sockaddrs */ #include #include +#include #include #include /* bus_dmamap_* in netmap_kern.h */ @@ -1198,6 +1199,13 @@ generic_netmap_attach(struct ifnet *ifp) int retval; u_int num_tx_desc, num_rx_desc; +#ifdef __FreeBSD__ + if (ifp->if_type == IFT_LOOP) { + D("if_loop is not supported by %s", __func__); + return EINVAL; + } +#endif + num_tx_desc = num_rx_desc = netmap_generic_ringsize; /* starting point */ nm_os_generic_find_num_desc(ifp, &num_tx_desc, &num_rx_desc); /* ignore errors */