On Wed, 2017-08-09 at 08:52 +0300, Nikolay Borisov wrote: > 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; > + > I would rather move this to inet_init_net(), since IGMP does not belong to TCP. Thanks !