IP multicast route code was reusing an skb which causes use after free and double free.
Signed-off-by: Stephen Hemminger <[EMAIL PROTECTED]> --- net/ipv4/ipmr.c | 22 ++++++++++++++++------ 1 files changed, 16 insertions(+), 6 deletions(-) diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c index ba33f86..f5d3d96 100644 --- a/net/ipv4/ipmr.c +++ b/net/ipv4/ipmr.c @@ -1580,6 +1580,7 @@ int ipmr_get_route(struct sk_buff *skb, cache = ipmr_cache_find(rt->rt_src, rt->rt_dst); if (cache==NULL) { + struct sk_buff *skb2; struct net_device *dev; int vif; @@ -1593,12 +1594,21 @@ int ipmr_get_route(struct sk_buff *skb, read_unlock(&mrt_lock); return -ENODEV; } - skb->nh.raw = skb_push(skb, sizeof(struct iphdr)); - skb->nh.iph->ihl = sizeof(struct iphdr)>>2; - skb->nh.iph->saddr = rt->rt_src; - skb->nh.iph->daddr = rt->rt_dst; - skb->nh.iph->version = 0; - err = ipmr_cache_unresolved(vif, skb); + + skb2 = alloc_skb(sizeof(struct iphdr) + sizeof(struct nlmsghdr), + GFP_ATOMIC); + if (!skb2) { + read_unlock(&mrt_lock); + return -ENOMEM; + } + + memset(skb2->data, 0, sizeof(struct iphdr)); + skb2->nh.raw = skb2->data; + skb2->nh.iph->ihl = sizeof(struct iphdr)>>2; + skb2->nh.iph->saddr = rt->rt_src; + skb2->nh.iph->daddr = rt->rt_dst; + + err = ipmr_cache_unresolved(vif, skb2); read_unlock(&mrt_lock); return err; } -- 1.4.0 - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html