diff options
| author | Patrick McHardy <kaber@trash.net> | 2008-02-19 17:17:52 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2008-02-19 17:17:52 -0800 |
| commit | e2b58a67b91dec07dfb40ca2056c64011ce8489d (patch) | |
| tree | 46e258092c2401b9cf6bc232ecfe96248a51982e /net/ipv4 | |
| parent | 94cb1503c799c0197e7ef5bad606fee5c84b99d8 (diff) | |
[NETFILTER]: {ip,ip6,nfnetlink}_queue: fix SKB_LINEAR_ASSERT when mangling packet data
As reported by Tomas Simonaitis <tomas.simonaitis@gmail.com>,
inserting new data in skbs queued over {ip,ip6,nfnetlink}_queue
triggers a SKB_LINEAR_ASSERT in skb_put().
Going back through the git history, it seems this bug is present since
at least 2.6.12-rc2, probably even since the removal of
skb_linearize() for netfilter.
Linearize non-linear skbs through skb_copy_expand() when enlarging
them. Tested by Thomas, fixes bugzilla #9933.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/netfilter/ip_queue.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/net/ipv4/netfilter/ip_queue.c b/net/ipv4/netfilter/ip_queue.c index 6bda1102851..fe05da41d6b 100644 --- a/net/ipv4/netfilter/ip_queue.c +++ b/net/ipv4/netfilter/ip_queue.c @@ -283,8 +283,8 @@ static int ipq_mangle_ipv4(ipq_verdict_msg_t *v, struct nf_queue_entry *e) { int diff; - int err; struct iphdr *user_iph = (struct iphdr *)v->payload; + struct sk_buff *nskb; if (v->data_len < sizeof(*user_iph)) return 0; @@ -296,14 +296,16 @@ ipq_mangle_ipv4(ipq_verdict_msg_t *v, struct nf_queue_entry *e) if (v->data_len > 0xFFFF) return -EINVAL; if (diff > skb_tailroom(e->skb)) { - err = pskb_expand_head(e->skb, 0, + nskb = skb_copy_expand(e->skb, 0, diff - skb_tailroom(e->skb), GFP_ATOMIC); - if (err) { + if (!nskb) { printk(KERN_WARNING "ip_queue: error " - "in mangle, dropping packet: %d\n", -err); - return err; + "in mangle, dropping packet\n"); + return -ENOMEM; } + kfree_skb(e->skb); + e->skb = nskb; } skb_put(e->skb, diff); } |