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| author | Eric Dumazet <eric.dumazet@gmail.com> | 2011-08-23 19:57:05 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2011-08-24 17:49:24 -0700 |
| commit | 22df13319d1fec30b8f9bcaadc295829647109bb (patch) | |
| tree | b61441ea39ac3c525746bfe8aaab9b6b5f9c6c63 /net | |
| parent | 4b275d7efa1c4412f0d572fcd7f78ed0919370b3 (diff) | |
| download | lwn-22df13319d1fec30b8f9bcaadc295829647109bb.tar.gz lwn-22df13319d1fec30b8f9bcaadc295829647109bb.zip | |
bridge: fix a possible use after free
br_multicast_ipv6_rcv() can call pskb_trim_rcsum() and therefore skb
head can be reallocated.
Cache icmp6_type field instead of dereferencing twice the struct
icmp6hdr pointer.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/bridge/br_multicast.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index 22d2d1af1c83..995cbe0ac0b2 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -1456,7 +1456,7 @@ static int br_multicast_ipv6_rcv(struct net_bridge *br, { struct sk_buff *skb2; const struct ipv6hdr *ip6h; - struct icmp6hdr *icmp6h; + u8 icmp6_type; u8 nexthdr; unsigned len; int offset; @@ -1502,9 +1502,9 @@ static int br_multicast_ipv6_rcv(struct net_bridge *br, __skb_pull(skb2, offset); skb_reset_transport_header(skb2); - icmp6h = icmp6_hdr(skb2); + icmp6_type = icmp6_hdr(skb2)->icmp6_type; - switch (icmp6h->icmp6_type) { + switch (icmp6_type) { case ICMPV6_MGM_QUERY: case ICMPV6_MGM_REPORT: case ICMPV6_MGM_REDUCTION: @@ -1544,7 +1544,7 @@ static int br_multicast_ipv6_rcv(struct net_bridge *br, BR_INPUT_SKB_CB(skb)->igmp = 1; - switch (icmp6h->icmp6_type) { + switch (icmp6_type) { case ICMPV6_MGM_REPORT: { struct mld_msg *mld; |