netfilter: conntrack: check for NEXTHDR_NONE before header sanity checking
NEXTHDR_NONE doesn't has an IPv6 option header, so the first check
for the length will always fail and results in a confusing message
"too short" if debugging enabled. With this patch, we check for
NEXTHDR_NONE before length sanity checkings are done.
Signed-off-by: Christoph Paasch <christoph.paasch@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c
index ed4d79a..058a5e4 100644
--- a/net/ipv6/netfilter/nf_conntrack_reasm.c
+++ b/net/ipv6/netfilter/nf_conntrack_reasm.c
@@ -528,14 +528,14 @@
if (!ipv6_ext_hdr(nexthdr)) {
return -1;
}
- if (len < (int)sizeof(struct ipv6_opt_hdr)) {
- pr_debug("too short\n");
- return -1;
- }
if (nexthdr == NEXTHDR_NONE) {
pr_debug("next header is none\n");
return -1;
}
+ if (len < (int)sizeof(struct ipv6_opt_hdr)) {
+ pr_debug("too short\n");
+ return -1;
+ }
if (skb_copy_bits(skb, start, &hdr, sizeof(hdr)))
BUG();
if (nexthdr == NEXTHDR_AUTH)