diff options
authorJesper Dangaard Brouer <hawk@comx.dk>2009-02-06 01:59:12 -0800
committerDavid S. Miller <davem@davemloft.net>2009-02-06 01:59:12 -0800
commit2783ef23128ad0a4b34e4121c1f7ff664785712f (patch)
parentefc683fc2a692735029067b4f939af2a3625e31d (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>
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;
return __udp4_lib_mcast_deliver(net, skb, uh,
saddr, daddr, udptable);