This is a note to let you know that I've just added the patch titled igmp: Fix regression caused by igmp sysctl namespace code. to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: igmp-fix-regression-caused-by-igmp-sysctl-namespace-code.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Fri Aug 11 09:10:20 PDT 2017 From: Nikolay Borisov <nborisov@xxxxxxxx> Date: Wed, 9 Aug 2017 14:38:04 +0300 Subject: igmp: Fix regression caused by igmp sysctl namespace code. From: Nikolay Borisov <nborisov@xxxxxxxx> [ Upstream commit 1714020e42b17135032c8606f7185b3fb2ba5d78 ] 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 into inet_init_net, 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> Signed-off-by: Nikolay Borisov <nborisov@xxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/ipv4/af_inet.c | 7 +++++++ net/ipv4/igmp.c | 6 ------ 2 files changed, 7 insertions(+), 6 deletions(-) --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -1693,6 +1693,13 @@ static __net_init int inet_init_net(stru net->ipv4.sysctl_ip_dynaddr = 0; net->ipv4.sysctl_ip_early_demux = 1; + /* Some igmp sysctl, whose values are always used */ + 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; } --- a/net/ipv4/igmp.c +++ b/net/ipv4/igmp.c @@ -2974,12 +2974,6 @@ static int __net_init igmp_net_init(stru 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: Patches currently in stable-queue which might be from nborisov@xxxxxxxx are queue-4.9/igmp-fix-regression-caused-by-igmp-sysctl-namespace-code.patch