From: Pablo Neira Ayuso <pablo@netfilter.org>
To: netfilter-devel@vger.kernel.org
Cc: davem@davemloft.net, netdev@vger.kernel.org
Subject: [PATCH 7/9] bridge: ebtables: don't crash when using dnat target in output chains
Date: Wed, 6 Nov 2019 12:12:35 +0100 [thread overview]
Message-ID: <20191106111237.3183-8-pablo@netfilter.org> (raw)
In-Reply-To: <20191106111237.3183-1-pablo@netfilter.org>
From: Florian Westphal <fw@strlen.de>
xt_in() returns NULL in the output hook, skip the pkt_type change for
that case, redirection only makes sense in broute/prerouting hooks.
Reported-by: Tom Yan <tom.ty89@gmail.com>
Cc: Linus Lüssing <linus.luessing@c0d3.blue>
Fixes: cf3cb246e277d ("bridge: ebtables: fix reception of frames DNAT-ed to bridge device/port")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
net/bridge/netfilter/ebt_dnat.c | 19 +++++++++++++++----
1 file changed, 15 insertions(+), 4 deletions(-)
diff --git a/net/bridge/netfilter/ebt_dnat.c b/net/bridge/netfilter/ebt_dnat.c
index ed91ea31978a..12a4f4d93681 100644
--- a/net/bridge/netfilter/ebt_dnat.c
+++ b/net/bridge/netfilter/ebt_dnat.c
@@ -20,7 +20,6 @@ static unsigned int
ebt_dnat_tg(struct sk_buff *skb, const struct xt_action_param *par)
{
const struct ebt_nat_info *info = par->targinfo;
- struct net_device *dev;
if (skb_ensure_writable(skb, ETH_ALEN))
return EBT_DROP;
@@ -33,10 +32,22 @@ ebt_dnat_tg(struct sk_buff *skb, const struct xt_action_param *par)
else
skb->pkt_type = PACKET_MULTICAST;
} else {
- if (xt_hooknum(par) != NF_BR_BROUTING)
- dev = br_port_get_rcu(xt_in(par))->br->dev;
- else
+ const struct net_device *dev;
+
+ switch (xt_hooknum(par)) {
+ case NF_BR_BROUTING:
dev = xt_in(par);
+ break;
+ case NF_BR_PRE_ROUTING:
+ dev = br_port_get_rcu(xt_in(par))->br->dev;
+ break;
+ default:
+ dev = NULL;
+ break;
+ }
+
+ if (!dev) /* NF_BR_LOCAL_OUT */
+ return info->target;
if (ether_addr_equal(info->mac, dev->dev_addr))
skb->pkt_type = PACKET_HOST;
--
2.11.0
next prev parent reply other threads:[~2019-11-06 11:12 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-06 11:12 [PATCH 0/9] Netfilter fixes for net Pablo Neira Ayuso
2019-11-06 11:12 ` [PATCH 1/9] netfilter: nf_tables_offload: check for register data length mismatches Pablo Neira Ayuso
2019-11-06 11:12 ` [PATCH 2/9] netfilter: ipset: Fix an error code in ip_set_sockfn_get() Pablo Neira Ayuso
2019-11-06 11:12 ` [PATCH 3/9] netfilter: ipset: Copy the right MAC address in hash:ip,mac IPv6 sets Pablo Neira Ayuso
2019-11-06 11:12 ` [PATCH 4/9] netfilter: ipset: Fix nla_policies to fully support NL_VALIDATE_STRICT Pablo Neira Ayuso
2019-11-06 11:12 ` [PATCH 5/9] netfilter: nf_tables: Align nft_expr private data to 64-bit Pablo Neira Ayuso
2019-11-06 11:12 ` [PATCH 6/9] netfilter: nf_tables: fix unexpected EOPNOTSUPP error Pablo Neira Ayuso
2019-11-06 11:12 ` Pablo Neira Ayuso [this message]
2019-11-06 11:12 ` [PATCH 8/9] netfilter: nf_tables: bogus EOPNOTSUPP on basechain update Pablo Neira Ayuso
2019-11-06 11:12 ` [PATCH 9/9] netfilter: nf_tables_offload: skip EBUSY on chain update Pablo Neira Ayuso
2019-11-07 5:17 ` [PATCH 0/9] Netfilter fixes for net David Miller
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20191106111237.3183-8-pablo@netfilter.org \
--to=pablo@netfilter.org \
--cc=davem@davemloft.net \
--cc=netdev@vger.kernel.org \
--cc=netfilter-devel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).