diff options
| author | Peter Huang (Peng) <peter.huangpeng@huawei.com> | 2012-04-19 20:12:51 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2012-04-24 00:16:24 -0400 |
| commit | a881e963c7fe1f226e991ee9bbe8907acda93294 (patch) | |
| tree | 5d2b2c01097300377821132f743cddd4fc90fed6 | |
| parent | 4d634ca35a8b38530b134ae92bc9e3cc9c23c030 (diff) | |
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.
[ Use "do { } while (0)" for nop br_drop_fake_rtable()
implementation -DaveM ]
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Peter Huang <peter.huangpeng@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/linux/netfilter_bridge.h | 9 | ||||
| -rw-r--r-- | include/net/dst.h | 1 | ||||
| -rw-r--r-- | net/bridge/br_forward.c | 1 | ||||
| -rw-r--r-- | 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 0ddd161f3b0..31d2844e657 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) do { } while (0) #endif /* CONFIG_BRIDGE_NETFILTER */ #endif /* __KERNEL__ */ diff --git a/include/net/dst.h b/include/net/dst.h index ff4da42fcfc..bed833d9796 100644 --- a/include/net/dst.h +++ b/include/net/dst.h @@ -59,6 +59,7 @@ 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 61f65344e71..a2098e3de50 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 dec4f381713..d7f49b63ab0 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; } |