From 97840cb67ff5ac8add836684f011fd838518d698 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Fri, 14 Nov 2014 18:14:33 +0100 Subject: netfilter: nfnetlink: fix insufficient validation in nfnetlink_bind Make sure the netlink group exists, otherwise you can trigger an out of bound array memory access from the netlink_bind() path. This splat can only be triggered only by superuser. [ 180.203600] UBSan: Undefined behaviour in ../net/netfilter/nfnetlink.c:467:28 [ 180.204249] index 9 is out of range for type 'int [9]' [ 180.204697] CPU: 0 PID: 1771 Comm: trinity-main Not tainted 3.18.0-rc4-mm1+ #122 [ 180.205365] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org +04/01/2014 [ 180.206498] 0000000000000018 0000000000000000 0000000000000009 ffff88007bdf7da8 [ 180.207220] ffffffff82b0ef5f 0000000000000092 ffffffff845ae2e0 ffff88007bdf7db8 [ 180.207887] ffffffff8199e489 ffff88007bdf7e18 ffffffff8199ea22 0000003900000000 [ 180.208639] Call Trace: [ 180.208857] dump_stack (lib/dump_stack.c:52) [ 180.209370] ubsan_epilogue (lib/ubsan.c:174) [ 180.209849] __ubsan_handle_out_of_bounds (lib/ubsan.c:400) [ 180.210512] nfnetlink_bind (net/netfilter/nfnetlink.c:467) [ 180.210986] netlink_bind (net/netlink/af_netlink.c:1483) [ 180.211495] SYSC_bind (net/socket.c:1541) Moreover, define the missing nf_tables and nf_acct multicast groups too. Reported-by: Andrey Ryabinin Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nfnetlink.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/net/netfilter/nfnetlink.c b/net/netfilter/nfnetlink.c index 6c5a915..13c2e17 100644 --- a/net/netfilter/nfnetlink.c +++ b/net/netfilter/nfnetlink.c @@ -47,6 +47,8 @@ static const int nfnl_group2type[NFNLGRP_MAX+1] = { [NFNLGRP_CONNTRACK_EXP_NEW] = NFNL_SUBSYS_CTNETLINK_EXP, [NFNLGRP_CONNTRACK_EXP_UPDATE] = NFNL_SUBSYS_CTNETLINK_EXP, [NFNLGRP_CONNTRACK_EXP_DESTROY] = NFNL_SUBSYS_CTNETLINK_EXP, + [NFNLGRP_NFTABLES] = NFNL_SUBSYS_NFTABLES, + [NFNLGRP_ACCT_QUOTA] = NFNL_SUBSYS_ACCT, }; void nfnl_lock(__u8 subsys_id) @@ -464,7 +466,12 @@ static void nfnetlink_rcv(struct sk_buff *skb) static int nfnetlink_bind(int group) { const struct nfnetlink_subsystem *ss; - int type = nfnl_group2type[group]; + int type; + + if (group <= NFNLGRP_NONE || group > NFNLGRP_MAX) + return -EINVAL; + + type = nfnl_group2type[group]; rcu_read_lock(); ss = nfnetlink_get_subsys(type); @@ -514,6 +521,9 @@ static int __init nfnetlink_init(void) { int i; + for (i = NFNLGRP_NONE + 1; i <= NFNLGRP_MAX; i++) + BUG_ON(nfnl_group2type[i] == NFNL_SUBSYS_NONE); + for (i=0; i Date: Mon, 17 Nov 2014 12:20:28 +0100 Subject: bridge: fix netfilter/NF_BR_LOCAL_OUT for own, locally generated queries MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Ebtables on the OUTPUT chain (NF_BR_LOCAL_OUT) would not work as expected for both locally generated IGMP and MLD queries. The IP header specific filter options are off by 14 Bytes for netfilter (actual output on interfaces is fine). NF_HOOK() expects the skb->data to point to the IP header, not the ethernet one (while dev_queue_xmit() does not). Luckily there is an br_dev_queue_push_xmit() helper function already - let's just use that. Introduced by eb1d16414339a6e113d89e2cca2556005d7ce919 ("bridge: Add core IGMP snooping support") Ebtables example: $ ebtables -I OUTPUT -p IPv6 -o eth1 --logical-out br0 \ --log --log-level 6 --log-ip6 --log-prefix="~EBT: " -j DROP before (broken): ~EBT: IN= OUT=eth1 MAC source = 02:04:64:a4:39:c2 \ MAC dest = 33:33:00:00:00:01 proto = 0x86dd IPv6 \ SRC=64a4:39c2:86dd:6000:0000:0020:0001:fe80 IPv6 \ DST=0000:0000:0000:0004:64ff:fea4:39c2:ff02, \ IPv6 priority=0x3, Next Header=2 after (working): ~EBT: IN= OUT=eth1 MAC source = 02:04:64:a4:39:c2 \ MAC dest = 33:33:00:00:00:01 proto = 0x86dd IPv6 \ SRC=fe80:0000:0000:0000:0004:64ff:fea4:39c2 IPv6 \ DST=ff02:0000:0000:0000:0000:0000:0000:0001, \ IPv6 priority=0x0, Next Header=0 Signed-off-by: Linus Lüssing Acked-by: Herbert Xu Signed-off-by: Pablo Neira Ayuso --- net/bridge/br_multicast.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index 648d79c..c465876 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -813,10 +813,9 @@ static void __br_multicast_send_query(struct net_bridge *br, return; if (port) { - __skb_push(skb, sizeof(struct ethhdr)); skb->dev = port->dev; NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev, - dev_queue_xmit); + br_dev_queue_push_xmit); } else { br_multicast_select_own_querier(br, ip, skb); netif_rx(skb); -- cgit v1.1