diff options
Diffstat (limited to 'net/ipv4/ip_fragment.c')
| -rw-r--r-- | net/ipv4/ip_fragment.c | 23 |
1 files changed, 13 insertions, 10 deletions
diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c index 448e6854682..eb9d63a570c 100644 --- a/net/ipv4/ip_fragment.c +++ b/net/ipv4/ip_fragment.c @@ -707,28 +707,27 @@ EXPORT_SYMBOL(ip_defrag); struct sk_buff *ip_check_defrag(struct sk_buff *skb, u32 user) { - const struct iphdr *iph; + struct iphdr iph; u32 len; if (skb->protocol != htons(ETH_P_IP)) return skb; - if (!pskb_may_pull(skb, sizeof(struct iphdr))) + if (!skb_copy_bits(skb, 0, &iph, sizeof(iph))) return skb; - iph = ip_hdr(skb); - if (iph->ihl < 5 || iph->version != 4) + if (iph.ihl < 5 || iph.version != 4) return skb; - if (!pskb_may_pull(skb, iph->ihl*4)) - return skb; - iph = ip_hdr(skb); - len = ntohs(iph->tot_len); - if (skb->len < len || len < (iph->ihl * 4)) + + len = ntohs(iph.tot_len); + if (skb->len < len || len < (iph.ihl * 4)) return skb; - if (ip_is_fragment(ip_hdr(skb))) { + if (ip_is_fragment(&iph)) { skb = skb_share_check(skb, GFP_ATOMIC); if (skb) { + if (!pskb_may_pull(skb, iph.ihl*4)) + return skb; if (pskb_trim_rcsum(skb, len)) return skb; memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); @@ -802,6 +801,10 @@ static int __net_init ip4_frags_ns_ctl_register(struct net *net) table[0].data = &net->ipv4.frags.high_thresh; table[1].data = &net->ipv4.frags.low_thresh; table[2].data = &net->ipv4.frags.timeout; + + /* Don't export sysctls to unprivileged users */ + if (net->user_ns != &init_user_ns) + table[0].procname = NULL; } hdr = register_net_sysctl(net, "net/ipv4", table); |