From: Florian Westphal Date: Mon, 6 Jan 2020 22:34:17 +0000 (+0100) Subject: netfilter: conntrack: dccp, sctp: handle null timeout argument X-Git-Tag: baikal/mips/sdk5.9~14596^2~2^2~1 X-Git-Url: https://git.baikalelectronics.ru/sdk/?a=commitdiff_plain;h=0f6732e65cebb4b9e6208dc25099f620a1517f38;p=kernel.git netfilter: conntrack: dccp, sctp: handle null timeout argument The timeout pointer can be NULL which means we should modify the per-nets timeout instead. All do this, except sctp and dccp which instead give: general protection fault: 0000 [#1] PREEMPT SMP KASAN net/netfilter/nf_conntrack_proto_dccp.c:682 ctnl_timeout_parse_policy+0x150/0x1d0 net/netfilter/nfnetlink_cttimeout.c:67 cttimeout_default_set+0x150/0x1c0 net/netfilter/nfnetlink_cttimeout.c:368 nfnetlink_rcv_msg+0xcf2/0xfb0 net/netfilter/nfnetlink.c:229 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 Reported-by: syzbot+46a4ad33f345d1dd346e@syzkaller.appspotmail.com Fixes: e416f5d68f4c9 ("netfilter: conntrack: remove get_timeout() indirection") Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- diff --git a/net/netfilter/nf_conntrack_proto_dccp.c b/net/netfilter/nf_conntrack_proto_dccp.c index b6b14db3955bf..b3f4a334f9d78 100644 --- a/net/netfilter/nf_conntrack_proto_dccp.c +++ b/net/netfilter/nf_conntrack_proto_dccp.c @@ -677,6 +677,9 @@ static int dccp_timeout_nlattr_to_obj(struct nlattr *tb[], unsigned int *timeouts = data; int i; + if (!timeouts) + timeouts = dn->dccp_timeout; + /* set default DCCP timeouts. */ for (i=0; idccp_timeout[i]; diff --git a/net/netfilter/nf_conntrack_proto_sctp.c b/net/netfilter/nf_conntrack_proto_sctp.c index fce3d93f15418..0399ae8f1188f 100644 --- a/net/netfilter/nf_conntrack_proto_sctp.c +++ b/net/netfilter/nf_conntrack_proto_sctp.c @@ -594,6 +594,9 @@ static int sctp_timeout_nlattr_to_obj(struct nlattr *tb[], struct nf_sctp_net *sn = nf_sctp_pernet(net); int i; + if (!timeouts) + timeouts = sn->timeouts; + /* set default SCTP timeouts. */ for (i=0; itimeouts[i];