This is a note to let you know that I've just added the patch titled act_connmark: avoid crashing on malformed nlattrs with null parms 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: act_connmark-avoid-crashing-on-malformed-nlattrs-with-null-parms.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 Sat Mar 18 22:03:25 CST 2017 From: Etienne Noss <etienne.noss@xxxxxxxxxx> Date: Fri, 10 Mar 2017 16:55:32 +0100 Subject: act_connmark: avoid crashing on malformed nlattrs with null parms From: Etienne Noss <etienne.noss@xxxxxxxxxx> [ Upstream commit 52491c7607c5527138095edf44c53169dc1ddb82 ] tcf_connmark_init does not check in its configuration if TCA_CONNMARK_PARMS is set, resulting in a null pointer dereference when trying to access it. [501099.043007] BUG: unable to handle kernel NULL pointer dereference at 0000000000000004 [501099.043039] IP: [<ffffffffc10c60fb>] tcf_connmark_init+0x8b/0x180 [act_connmark] ... [501099.044334] Call Trace: [501099.044345] [<ffffffffa47270e8>] ? tcf_action_init_1+0x198/0x1b0 [501099.044363] [<ffffffffa47271b0>] ? tcf_action_init+0xb0/0x120 [501099.044380] [<ffffffffa47250a4>] ? tcf_exts_validate+0xc4/0x110 [501099.044398] [<ffffffffc0f5fa97>] ? u32_set_parms+0xa7/0x270 [cls_u32] [501099.044417] [<ffffffffc0f60bf0>] ? u32_change+0x680/0x87b [cls_u32] [501099.044436] [<ffffffffa4725d1d>] ? tc_ctl_tfilter+0x4dd/0x8a0 [501099.044454] [<ffffffffa44a23a1>] ? security_capable+0x41/0x60 [501099.044471] [<ffffffffa470ca01>] ? rtnetlink_rcv_msg+0xe1/0x220 [501099.044490] [<ffffffffa470c920>] ? rtnl_newlink+0x870/0x870 [501099.044507] [<ffffffffa472cc61>] ? netlink_rcv_skb+0xa1/0xc0 [501099.044524] [<ffffffffa47073f4>] ? rtnetlink_rcv+0x24/0x30 [501099.044541] [<ffffffffa472c634>] ? netlink_unicast+0x184/0x230 [501099.044558] [<ffffffffa472c9d8>] ? netlink_sendmsg+0x2f8/0x3b0 [501099.044576] [<ffffffffa46d8880>] ? sock_sendmsg+0x30/0x40 [501099.044592] [<ffffffffa46d8e03>] ? SYSC_sendto+0xd3/0x150 [501099.044608] [<ffffffffa425fda1>] ? __do_page_fault+0x2d1/0x510 [501099.044626] [<ffffffffa47fbd7b>] ? system_call_fast_compare_end+0xc/0x9b Fixes: 22a5dc0e5e3e ("net: sched: Introduce connmark action") Signed-off-by: Étienne Noss <etienne.noss@xxxxxxxxxx> Signed-off-by: Victorien Molle <victorien.molle@xxxxxxxxxx> Acked-by: Cong Wang <xiyou.wangcong@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/sched/act_connmark.c | 3 +++ 1 file changed, 3 insertions(+) --- a/net/sched/act_connmark.c +++ b/net/sched/act_connmark.c @@ -113,6 +113,9 @@ static int tcf_connmark_init(struct net if (ret < 0) return ret; + if (!tb[TCA_CONNMARK_PARMS]) + return -EINVAL; + parm = nla_data(tb[TCA_CONNMARK_PARMS]); if (!tcf_hash_check(tn, parm->index, a, bind)) { Patches currently in stable-queue which might be from etienne.noss@xxxxxxxxxx are queue-4.9/act_connmark-avoid-crashing-on-malformed-nlattrs-with-null-parms.patch