diff options
| author | Jesper Dangaard Brouer <hawk@comx.dk> | 2009-02-06 01:59:12 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2009-02-06 01:59:12 -0800 |
| commit | 2783ef23128ad0a4b34e4121c1f7ff664785712f (patch) | |
| tree | 1e0ada9b370ffc967b138dfb7d7c5464a0d4f438 | |
| parent | efc683fc2a692735029067b4f939af2a3625e31d (diff) | |
udp: Fix potential wrong ip_hdr(skb) pointers
Like the UDP header fix, pskb_may_pull() can potentially
alter the SKB buffer. Thus the saddr and daddr, pointers
may point to the old skb->data buffer.
I haven't seen corruptions, as its only seen if the old
skb->data buffer were reallocated by another user and
written into very quickly (or poison'd by SLAB debugging).
Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/ipv4/udp.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index cc3a0a06c00..c47c989cb1f 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1234,8 +1234,7 @@ int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, struct udphdr *uh; unsigned short ulen; struct rtable *rt = (struct rtable*)skb->dst; - __be32 saddr = ip_hdr(skb)->saddr; - __be32 daddr = ip_hdr(skb)->daddr; + __be32 saddr, daddr; struct net *net = dev_net(skb->dev); /* @@ -1259,6 +1258,9 @@ int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, if (udp4_csum_init(skb, uh, proto)) goto csum_error; + saddr = ip_hdr(skb)->saddr; + daddr = ip_hdr(skb)->daddr; + if (rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST)) return __udp4_lib_mcast_deliver(net, skb, uh, saddr, daddr, udptable); |