Messages in this thread Patch in this message | | | From | Kamal Mostafa <> | Subject | [PATCH 3.13.y-ckt 40/43] ipv6: re-enable fragment header matching in ipv6_find_hdr | Date | Tue, 22 Mar 2016 14:03:55 -0700 |
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3.13.11-ckt37 -stable review patch. If anyone has any objections, please let me know.
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From: Florian Westphal <fw@strlen.de>
commit 5d150a985520bbe3cb2aa1ceef24a7e32f20c15f upstream.
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> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- net/ipv6/exthdrs_core.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/net/ipv6/exthdrs_core.c b/net/ipv6/exthdrs_core.c index 8af3eb5..c7c8f71 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) { -- 2.7.0
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