From 8f2598f3be634610dfc9b5da4bd9da5c32757bbf Mon Sep 17 00:00:00 2001 From: karels Date: Tue, 12 Nov 2019 01:03:08 +0000 Subject: [PATCH] Fix netstat -gs with ip_mroute module and/or vnet The code for "netstat -gs -f inet" failed if the kernel namelist did not include the _mrtstat symbol. However, that symbol is not in a standard kernel even with the ip_mroute module loaded, where the functionality is available. It is also not in a kernel with MROUTING but also VIMAGE, as there can be multiple sets of stats. However, when running the command on a live system, the symbol is not used; a sysctl is used. Go ahead and try the sysctl in any case, and complain that IPv4 MROUTING is not present only if the sysctl fails with ENOENT. Also fail if _mrtstat is not defined when running on a core file; netstat doesn't know about vnets, so can only work if MROUTING was included, and VIMAGE was not. Reviewed by: bz MFC after: 1 week Differential Revision: https://reviews.freebsd.org/D22311 --- usr.bin/netstat/mroute.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/usr.bin/netstat/mroute.c b/usr.bin/netstat/mroute.c index afc5458e5e1..04b7ead03b7 100644 --- a/usr.bin/netstat/mroute.c +++ b/usr.bin/netstat/mroute.c @@ -409,14 +409,12 @@ mrt_stats() mstaddr = nl[N_MRTSTAT].n_value; - if (mstaddr == 0) { - fprintf(stderr, "No IPv4 MROUTING kernel support.\n"); - return; - } - if (fetch_stats("net.inet.ip.mrtstat", mstaddr, &mrtstat, - sizeof(mrtstat), kread_counters) != 0) + sizeof(mrtstat), kread_counters) != 0) { + if ((live && errno == ENOENT) || (!live && mstaddr == 0)) + fprintf(stderr, "No IPv4 MROUTING kernel support.\n"); return; + } xo_emit("{T:IPv4 multicast forwarding}:\n"); -- 2.45.0