lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Wed, 8 Jan 2020 10:59:38 +0100 From: Florian Westphal <fw@...len.de> To: netfilter-devel@...r.kernel.org Cc: netdev@...r.kernel.org, syzkaller-bugs@...glegroups.com, Florian Westphal <fw@...len.de>, Jozsef Kadlecsik <kadlec@...ckhole.kfki.hu>, syzbot+34bd2369d38707f3f4a7@...kaller.appspotmail.com Subject: [PATCH nf] netfilter: ipset: avoid null deref when IPSET_ATTR_LINENO is present The set uadt functions assume lineno is never NULL, but it is in case of ip_set_utest(). syzkaller managed to generate a netlink message that calls this with LINENO attr present: general protection fault: 0000 [#1] PREEMPT SMP KASAN RIP: 0010:hash_mac4_uadt+0x1bc/0x470 net/netfilter/ipset/ip_set_hash_mac.c:104 Call Trace: ip_set_utest+0x55b/0x890 net/netfilter/ipset/ip_set_core.c:1867 nfnetlink_rcv_msg+0xcf2/0xfb0 net/netfilter/nfnetlink.c:229 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 nfnetlink_rcv+0x1ba/0x460 net/netfilter/nfnetlink.c:563 pass a dummy lineno storage, its easier than patching all set implementations. This seems to be a day-0 bug. Cc: Jozsef Kadlecsik <kadlec@...ckhole.kfki.hu> Reported-by: syzbot+34bd2369d38707f3f4a7@...kaller.appspotmail.com Fixes: a7b4f989a6294 ("netfilter: ipset: IP set core support") Signed-off-by: Florian Westphal <fw@...len.de> --- net/netfilter/ipset/ip_set_core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c index 169e0a04f814..cf895bc80871 100644 --- a/net/netfilter/ipset/ip_set_core.c +++ b/net/netfilter/ipset/ip_set_core.c @@ -1848,6 +1848,7 @@ static int ip_set_utest(struct net *net, struct sock *ctnl, struct sk_buff *skb, struct ip_set *set; struct nlattr *tb[IPSET_ATTR_ADT_MAX + 1] = {}; int ret = 0; + u32 lineno; if (unlikely(protocol_min_failed(attr) || !attr[IPSET_ATTR_SETNAME] || @@ -1864,7 +1865,7 @@ static int ip_set_utest(struct net *net, struct sock *ctnl, struct sk_buff *skb, return -IPSET_ERR_PROTOCOL; rcu_read_lock_bh(); - ret = set->variant->uadt(set, tb, IPSET_TEST, NULL, 0, 0); + ret = set->variant->uadt(set, tb, IPSET_TEST, &lineno, 0, 0); rcu_read_unlock_bh(); /* Userspace can't trigger element to be re-added */ if (ret == -EAGAIN) -- 2.24.1
Powered by blists - more mailing lists