diff options
| author | Herbert Xu <herbert@gondor.apana.org.au> | 2010-07-05 14:50:08 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2010-07-05 20:08:06 -0700 |
| commit | 7f285fa78d4b81b8458f05e77fb6b46245121b4e (patch) | |
| tree | a4fa0d8e5cd102bb3aed7ad984de31e8a5f7575e | |
| parent | bcfcc450baaaa44afc1d3c51ef96a53338ff0eb2 (diff) | |
| download | linux-7f285fa78d4b81b8458f05e77fb6b46245121b4e.tar.bz2 | |
bridge br_multicast: BUG: unable to handle kernel NULL pointer dereference
On Tue, Jul 06, 2010 at 08:48:35AM +0800, Herbert Xu wrote:
>
> bridge: Restore NULL check in br_mdb_ip_get
Resend with proper attribution.
bridge: Restore NULL check in br_mdb_ip_get
Somewhere along the line the NULL check in br_mdb_ip_get went
AWOL, causing crashes when we receive an IGMP packet with no
multicast table allocated.
This patch restores it and ensures all br_mdb_*_get functions
use it.
Reported-by: Frank Arnold <frank.arnold@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Thanks,
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/bridge/br_multicast.c | 21 |
1 files changed, 12 insertions, 9 deletions
diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index 9d21d98ae5fa..27ae946363f1 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -99,6 +99,15 @@ static struct net_bridge_mdb_entry *__br_mdb_ip_get( return NULL; } +static struct net_bridge_mdb_entry *br_mdb_ip_get( + struct net_bridge_mdb_htable *mdb, struct br_ip *dst) +{ + if (!mdb) + return NULL; + + return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst)); +} + static struct net_bridge_mdb_entry *br_mdb_ip4_get( struct net_bridge_mdb_htable *mdb, __be32 dst) { @@ -107,7 +116,7 @@ static struct net_bridge_mdb_entry *br_mdb_ip4_get( br_dst.u.ip4 = dst; br_dst.proto = htons(ETH_P_IP); - return __br_mdb_ip_get(mdb, &br_dst, __br_ip4_hash(mdb, dst)); + return br_mdb_ip_get(mdb, &br_dst); } #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) @@ -119,23 +128,17 @@ static struct net_bridge_mdb_entry *br_mdb_ip6_get( ipv6_addr_copy(&br_dst.u.ip6, dst); br_dst.proto = htons(ETH_P_IPV6); - return __br_mdb_ip_get(mdb, &br_dst, __br_ip6_hash(mdb, dst)); + return br_mdb_ip_get(mdb, &br_dst); } #endif -static struct net_bridge_mdb_entry *br_mdb_ip_get( - struct net_bridge_mdb_htable *mdb, struct br_ip *dst) -{ - return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst)); -} - struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br, struct sk_buff *skb) { struct net_bridge_mdb_htable *mdb = br->mdb; struct br_ip ip; - if (!mdb || br->multicast_disabled) + if (br->multicast_disabled) return NULL; if (BR_INPUT_SKB_CB(skb)->igmp) |