Commit dcd87999d415 ("igmp: net: Move igmp namespace init to correct file") moved the igmp sysctls initialization from tcp_sk_init to igmp_net_init. This function is only called as part of per-namespace initialization, only if CONFIG_IP_MULTICAST is defined, otherwise igmp_mc_init() call in ip_init is compiled out, casuing the igmp pernet ops to not be registerd and those sysctl being left initialized with 0. However, there are certain functions, such as ip_mc_join_group which are always compiled and make use of some of those sysctls. Let's do a partial revert of the aforementioned commit and move the sysctl initialization back into tcp_sk_init, that way they will always have sane values. Fixes: dcd87999d415 ("igmp: net: Move igmp namespace init to correct file") Link: https://bugzilla.kernel.org/show_bug.cgi?id=196595 Reported-by: Gerardo Exequiel Pozzi <vmlinuz386@xxxxxxxxx> Tested-by: Gerardo Exequiel Pozzi <vmlinuz386@xxxxxxxxx> Signed-off-by: Nikolay Borisov <nborisov@xxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> # 4.6 --- net/ipv4/igmp.c | 6 ------ net/ipv4/tcp_ipv4.c | 6 ++++++ 2 files changed, 6 insertions(+), 6 deletions(-) diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c index 28f14afd0dd3..498706b072fb 100644 --- a/net/ipv4/igmp.c +++ b/net/ipv4/igmp.c @@ -2974,12 +2974,6 @@ static int __net_init igmp_net_init(struct net *net) goto out_sock; } - /* Sysctl initialization */ - net->ipv4.sysctl_igmp_max_memberships = 20; - net->ipv4.sysctl_igmp_max_msf = 10; - /* IGMP reports for link-local multicast groups are enabled by default */ - net->ipv4.sysctl_igmp_llm_reports = 1; - net->ipv4.sysctl_igmp_qrv = 2; return 0; out_sock: diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index a20e7f03d5f7..64ba2c93d396 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -2528,6 +2528,12 @@ static int __net_init tcp_sk_init(struct net *net) net->ipv4.sysctl_tcp_window_scaling = 1; net->ipv4.sysctl_tcp_timestamps = 1; + net->ipv4.sysctl_igmp_max_memberships = 20; + net->ipv4.sysctl_igmp_max_msf = 10; + /* IGMP reports for link-local multicast groups are enabled by default */ + net->ipv4.sysctl_igmp_llm_reports = 1; + net->ipv4.sysctl_igmp_qrv = 2; + return 0; fail: tcp_sk_exit(net); -- 2.7.4