diff options
| author | Florian Westphal <fw@strlen.de> | 2016-03-01 16:15:16 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-03-03 16:35:20 -0500 |
| commit | 5d150a985520bbe3cb2aa1ceef24a7e32f20c15f (patch) | |
| tree | 9bcc235f8cd4983e0400a80bbb8e36e1cd33847f /net | |
| parent | bf13c94ccb33c3182efc92ce4989506a0f541243 (diff) | |
ipv6: re-enable fragment header matching in ipv6_find_hdr
When ipv6_find_hdr is used to find a fragment header
(caller specifies target NEXTHDR_FRAGMENT) we erronously return
-ENOENT for all fragments with nonzero offset.
Before commit 9195bb8e381d, when target was specified, we did not
enter the exthdr walk loop as nexthdr == target so this used to work.
Now we do (so we can skip empty route headers). When we then stumble upon
a frag with nonzero frag_off we must return -ENOENT ("header not found")
only if the caller did not specifically request NEXTHDR_FRAGMENT.
This allows nfables exthdr expression to match ipv6 fragments, e.g. via
nft add rule ip6 filter input frag frag-off gt 0
Fixes: 9195bb8e381d ("ipv6: improve ipv6_find_hdr() to skip empty routing headers")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv6/exthdrs_core.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/net/ipv6/exthdrs_core.c b/net/ipv6/exthdrs_core.c index 5c5d23e59da5..9508a20fbf61 100644 --- a/net/ipv6/exthdrs_core.c +++ b/net/ipv6/exthdrs_core.c @@ -257,7 +257,11 @@ int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, *fragoff = _frag_off; return hp->nexthdr; } - return -ENOENT; + if (!found) + return -ENOENT; + if (fragoff) + *fragoff = _frag_off; + break; } hdrlen = 8; } else if (nexthdr == NEXTHDR_AUTH) { |