This reverts commit 0ed4229b08c1 ("ipv6: defrag: drop non-last frags smaller than min mtu"). While one should not get fragments smaller than the IPv6 minimum MTU, not handling crafted packets in the TAHI IPv6 conformance test suite (v6eval) for IPv6 Ready Logo results in 18 failures representing over 5% of the score.
Cc: Florian Westphal <f...@strlen.de> Signed-off-by: Mike Manning <mmann...@vyatta.att-mail.com> --- The failures which are reverted by this fix are: Section 1: RFC 2460 - IPv6 Specification Test v6LC.1.2.4: Extension Header Processing Order 33-34 Test v6LC.1.3.1: Fragment Reassembly 67-72 Test v6LC.1.3.2: Reassembly Time Exceeded 73-76 Test v6LC.1.3.3: Fragment Header M-Bit Set, Payload Length Invalid 78 Section 5: RFC 4443 - ICMPv6 Test v6LC.5.1.6: Erroneous Header Field (Parameter Problem Generation) 20 Erroneous Header Field (Parameter Problem Generation) Test v6LC.5.1.10: Error Condition With Multicast Destination 31 Part B: Echo Request Reassembly Timeout Test v6LC.5.1.11: Error Condition With Non-Unique Source - Unspecified 35 Part C: Echo Request Reassembly Timeout (Routers and Hosts) Test v6LC.5.1.12: Error Condition With Non-Unique Source - Multicast 40 Part C: Echo Request Reassembly Timeout (Routers and Hosts) Test v6LC.5.1.13: Error Condition With Non-Unique Source Anycast (Routers Only) 45 Part C: Echo Request Reassembly Timeout net/ipv6/netfilter/nf_conntrack_reasm.c | 4 ---- net/ipv6/reassembly.c | 4 ---- 2 files changed, 8 deletions(-) diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c index 8f68a518d9db..8c69c4fc78d8 100644 --- a/net/ipv6/netfilter/nf_conntrack_reasm.c +++ b/net/ipv6/netfilter/nf_conntrack_reasm.c @@ -559,10 +559,6 @@ int nf_ct_frag6_gather(struct net *net, struct sk_buff *skb, u32 user) hdr = ipv6_hdr(skb); fhdr = (struct frag_hdr *)skb_transport_header(skb); - if (skb->len - skb_network_offset(skb) < IPV6_MIN_MTU && - fhdr->frag_off & htons(IP6_MF)) - return -EINVAL; - skb_orphan(skb); fq = fq_find(net, fhdr->identification, user, hdr, skb->dev ? skb->dev->ifindex : 0); diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c index 5c5b4f79296e..b4e558ab39fa 100644 --- a/net/ipv6/reassembly.c +++ b/net/ipv6/reassembly.c @@ -456,10 +456,6 @@ static int ipv6_frag_rcv(struct sk_buff *skb) return 1; } - if (skb->len - skb_network_offset(skb) < IPV6_MIN_MTU && - fhdr->frag_off & htons(IP6_MF)) - goto fail_hdr; - iif = skb->dev ? skb->dev->ifindex : 0; fq = fq_find(net, fhdr->identification, hdr, iif); if (fq) { -- 2.11.0