3.2-stable review patch. If anyone has any objections, please let me know.
------------------ From: "Peter Huang (Peng)" <[email protected]> [ Upstream commit a881e963c7fe1f226e991ee9bbe8907acda93294 ] 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 <[email protected]> Signed-off-by: Peter Huang <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Ben Hutchings <[email protected]> --- 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..31d2844 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 75766b4..65bca65 100644 --- a/include/net/dst.h +++ b/include/net/dst.h @@ -54,6 +54,7 @@ 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 ee64287..e221f88 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 fa8b8f7..577ea5d 100644 --- a/net/bridge/br_netfilter.c +++ b/net/bridge/br_netfilter.c @@ -147,7 +147,7 @@ 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; } @@ -687,11 +687,7 @@ 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; } -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
