| 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
| ||
|
Message-id: <4F90FE63.9060800@huawei.com>
Date: Fri, 20 Apr 2012 14:12:51 +0800
From: "Peter Huang(Peng)" <peter.huangpeng@...wei.com>
To: Stephen Hemminger <shemminger@...tta.com>,
"'David S. Miller'" <davem@...emloft.net>, netdev@...r.kernel.org
Cc: Eric Dumazet <eric.dumazet@...il.com>, peter.huangpeng@...il.com,
linux-kernel@...r.kernel.org, harry.majun@...wei.com,
peter.huangpeng@...wei.com,
Massimo Cetra <ctrix+debianbugs@...ynet.it>
Subject: [PATCH v4] set fake_rtable's dst to NULL to avoid kernel Oops
bridge: set fake_rtable's dst to NULL to avoid kernel Oops
when bridge is deleted before tap/vif device's delete, kernel may
encounter an oops because of NULL reference to fake_rtable's dst.
Set fake_rtable's dst to NULL before sending packets out can solve
this problem.
v4 reformat, change br_drop_fake_rtable(skb) to {}
v3 enrich commit header
v2 introducing new flag DST_FAKE_RTABLE to dst_entry struct.
Acked-by: Eric Dumazet <eric.dumazet@...il.com>
Signed-off-by: Peter Huang <peter.huangpeng@...wei.com>
---
include/linux/netfilter_bridge.h | 9 +++++++++
include/net/dst.h | 1 +
net/bridge/br_forward.c | 1 +
net/bridge/br_netfilter.c | 8 ++------
4 files changed, 13 insertions(+), 6 deletions(-)
diff --git a/include/linux/netfilter_bridge.h b/include/linux/netfilter_bridge.h
index 0ddd161..3da2798 100644
--- a/include/linux/netfilter_bridge.h
+++ b/include/linux/netfilter_bridge.h
@@ -104,9 +104,18 @@ struct bridge_skb_cb {
} daddr;
};
+static inline void br_drop_fake_rtable(struct sk_buff *skb)
+{
+ struct dst_entry *dst = skb_dst(skb);
+
+ if (dst && (dst->flags & DST_FAKE_RTABLE))
+ skb_dst_drop(skb);
+}
+
#else
#define nf_bridge_maybe_copy_header(skb) (0)
#define nf_bridge_pad(skb) (0)
+#define br_drop_fake_rtable(skb) {}
#endif /* CONFIG_BRIDGE_NETFILTER */
#endif /* __KERNEL__ */
diff --git a/include/net/dst.h b/include/net/dst.h
index 59c5d18..b094030 100644
--- a/include/net/dst.h
+++ b/include/net/dst.h
@@ -55,6 +55,7 @@ struct dst_entry {
#define DST_NOCACHE 0x0010
#define DST_NOCOUNT 0x0020
#define DST_NOPEER 0x0040
+#define DST_FAKE_RTABLE 0x0080
short error;
short obsolete;
diff --git a/net/bridge/br_forward.c b/net/bridge/br_forward.c
index 61f6534..a2098e3 100644
--- a/net/bridge/br_forward.c
+++ b/net/bridge/br_forward.c
@@ -47,6 +47,7 @@ int br_dev_queue_push_xmit(struct sk_buff *skb)
kfree_skb(skb);
} else {
skb_push(skb, ETH_HLEN);
+ br_drop_fake_rtable(skb);
dev_queue_xmit(skb);
}
diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c
index dec4f38..d7f49b6 100644
--- a/net/bridge/br_netfilter.c
+++ b/net/bridge/br_netfilter.c
@@ -156,7 +156,7 @@ void br_netfilter_rtable_init(struct net_bridge *br)
rt->dst.dev = br->dev;
rt->dst.path = &rt->dst;
dst_init_metrics(&rt->dst, br_dst_default_metrics, true);
- rt->dst.flags = DST_NOXFRM | DST_NOPEER;
+ rt->dst.flags = DST_NOXFRM | DST_NOPEER | DST_FAKE_RTABLE;
rt->dst.ops = &fake_dst_ops;
}
@@ -694,11 +694,7 @@ static unsigned int br_nf_local_in(unsigned int hook, struct sk_buff *skb,
const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
- struct rtable *rt = skb_rtable(skb);
-
- if (rt && rt == bridge_parent_rtable(in))
- skb_dst_drop(skb);
-
+ br_drop_fake_rtable(skb);
return NF_ACCEPT;
}
--
1.7.1
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists