From: Pablo Neira Ayuso <pablo@netfilter.org>
To: netfilter-devel@vger.kernel.org
Cc: davem@davemloft.net, netdev@vger.kernel.org
Subject: [PATCH 3/6] netfilter: nfnetlink: Fix use after free when it fails to process batch
Date: Fri, 9 May 2014 12:56:04 +0200 [thread overview]
Message-ID: <1399632967-4423-4-git-send-email-pablo@netfilter.org> (raw)
In-Reply-To: <1399632967-4423-1-git-send-email-pablo@netfilter.org>
From: Denys Fedoryshchenko <nuclearcat@nuclearcat.com>
This bug manifests when calling the nft command line tool without
nf_tables kernel support.
kernel message:
[ 44.071555] Netfilter messages via NETLINK v0.30.
[ 44.072253] BUG: unable to handle kernel NULL pointer dereference at 0000000000000119
[ 44.072264] IP: [<ffffffff8171db1f>] netlink_getsockbyportid+0xf/0x70
[ 44.072272] PGD 7f2b74067 PUD 7f2b73067 PMD 0
[ 44.072277] Oops: 0000 [#1] SMP
[...]
[ 44.072369] Call Trace:
[ 44.072373] [<ffffffff8171fd81>] netlink_unicast+0x91/0x200
[ 44.072377] [<ffffffff817206c9>] netlink_ack+0x99/0x110
[ 44.072381] [<ffffffffa004b951>] nfnetlink_rcv+0x3c1/0x408 [nfnetlink]
[ 44.072385] [<ffffffff8171fde3>] netlink_unicast+0xf3/0x200
[ 44.072389] [<ffffffff817201ef>] netlink_sendmsg+0x2ff/0x740
[ 44.072394] [<ffffffff81044752>] ? __mmdrop+0x62/0x90
[ 44.072398] [<ffffffff816dafdb>] sock_sendmsg+0x8b/0xc0
[ 44.072403] [<ffffffff812f1af5>] ? copy_user_enhanced_fast_string+0x5/0x10
[ 44.072406] [<ffffffff816dbb6c>] ? move_addr_to_kernel+0x2c/0x50
[ 44.072410] [<ffffffff816db423>] ___sys_sendmsg+0x3c3/0x3d0
[ 44.072415] [<ffffffff811301ba>] ? handle_mm_fault+0xa9a/0xc60
[ 44.072420] [<ffffffff811362d6>] ? mmap_region+0x166/0x5a0
[ 44.072424] [<ffffffff817da84c>] ? __do_page_fault+0x1dc/0x510
[ 44.072428] [<ffffffff812b8b2c>] ? apparmor_capable+0x1c/0x60
[ 44.072435] [<ffffffff817d6e9a>] ? _raw_spin_unlock_bh+0x1a/0x20
[ 44.072439] [<ffffffff816dfc86>] ? release_sock+0x106/0x150
[ 44.072443] [<ffffffff816dc212>] __sys_sendmsg+0x42/0x80
[ 44.072446] [<ffffffff816dc262>] SyS_sendmsg+0x12/0x20
[ 44.072450] [<ffffffff817df616>] system_call_fastpath+0x1a/0x1f
Signed-off-by: Denys Fedoryshchenko <nuclearcat@nuclearcat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
net/netfilter/nfnetlink.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/net/netfilter/nfnetlink.c b/net/netfilter/nfnetlink.c
index e009087..23ef77c 100644
--- a/net/netfilter/nfnetlink.c
+++ b/net/netfilter/nfnetlink.c
@@ -256,15 +256,15 @@ replay:
#endif
{
nfnl_unlock(subsys_id);
- kfree_skb(nskb);
- return netlink_ack(skb, nlh, -EOPNOTSUPP);
+ netlink_ack(skb, nlh, -EOPNOTSUPP);
+ return kfree_skb(nskb);
}
}
if (!ss->commit || !ss->abort) {
nfnl_unlock(subsys_id);
- kfree_skb(nskb);
- return netlink_ack(skb, nlh, -EOPNOTSUPP);
+ netlink_ack(skb, nlh, -EOPNOTSUPP);
+ return kfree_skb(skb);
}
while (skb->len >= nlmsg_total_size(0)) {
--
1.7.10.4
next prev parent reply other threads:[~2014-05-09 10:56 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-05-09 10:56 [PATCH 0/6] Netfilter fixes for net Pablo Neira Ayuso
2014-05-09 10:56 ` [PATCH 1/6] netfilter: ctnetlink: don't add null bindings if no nat requested Pablo Neira Ayuso
2014-05-09 10:56 ` [PATCH 2/6] netfilter: ipv4: defrag: set local_df flag on defragmented skb Pablo Neira Ayuso
2014-05-09 10:56 ` Pablo Neira Ayuso [this message]
2014-05-09 10:56 ` [PATCH 4/6] ipv4: fix "conntrack zones" support for defrag user check in ip_expire Pablo Neira Ayuso
2014-05-09 10:56 ` [PATCH 5/6] bridge: superfluous skb->nfct check in br_nf_dev_queue_xmit Pablo Neira Ayuso
2014-05-09 10:56 ` [PATCH 6/6] netfilter: Fix potential use after free in ip6_route_me_harder() Pablo Neira Ayuso
2014-05-09 17:17 ` [PATCH 0/6] Netfilter fixes for net David Miller
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