Commit 5ef0ae84 authored Oct 15, 2018 by Joe Stringer Committed by Alexei Starovoitov Oct 15, 2018

bpf: Fix IPv6 dport byte-order in bpf_sk_lookup



Commit 6acc9b43 ("bpf: Add helper to retrieve socket in BPF")
mistakenly passed the destination port in network byte-order to the IPv6
TCP/UDP socket lookup functions, which meant that BPF writers would need
to either manually swap the byte-order of this field or otherwise IPv6
sockets could not be located via this helper.

Fix the issue by swapping the byte-order appropriately in the helper.
This also makes the API more consistent with the IPv4 version.

Fixes: 6acc9b43 ("bpf: Add helper to retrieve socket in BPF")
Signed-off-by: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

parent 8a615c6b

net/core/filter.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -4721,17 +4721,18 @@ static struct sock sk_lookup(struct net net, struct bpf_sock_tuple *tuple,
		} else {
		struct in6_addr src6 = (struct in6_addr )&tuple->ipv6.saddr;
		struct in6_addr dst6 = (struct in6_addr )&tuple->ipv6.daddr;
		u16 hnum = ntohs(tuple->ipv6.dport);
		int sdif = inet6_sdif(skb);

		if (proto == IPPROTO_TCP)
		sk = __inet6_lookup(net, &tcp_hashinfo, skb, 0,
		src6, tuple->ipv6.sport,
		dst6, tuple->ipv6.dport,
		dst6, hnum,
		dif, sdif, &refcounted);
		else if (likely(ipv6_bpf_stub))
		sk = ipv6_bpf_stub->udp6_lib_lookup(net,
		src6, tuple->ipv6.sport,
		dst6, tuple->ipv6.dport,
		dst6, hnum,
		dif, sdif,
		&udp_table, skb);
		#endif

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