Le 06/06/2019 à 09:15, Olivier Matz a écrit :
> The following code returns EFAULT (Bad address):
>
> s = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6);
> setsockopt(s, SOL_IPV6, IPV6_HDRINCL, 1);
> sendto(ipv6_icmp6_packet, addr); /* returns -1, errno = EFAULT */
>
> The IPv4 equivalent code works. A workaround is to use IPPROTO_RAW
> instead of IPPROTO_ICMPV6.
>
> The failure happens because 2 bytes are eaten from the msghdr by
> rawv6_probe_proto_opt() starting from commit 19e3c66b52ca ("ipv6
> equivalent of "ipv4: Avoid reading user iov twice after
> raw_probe_proto_opt""), but at that time it was not a problem because
> IPV6_HDRINCL was not yet introduced.
>
> Only eat these 2 bytes if hdrincl == 0.
>
> Fixes: 715f504b1189 ("ipv6: add IPV6_HDRINCL option for raw sockets")
> Signed-off-by: Olivier Matz <olivier.m...@6wind.com>
Acked-by: Nicolas Dichtel <nicolas.dich...@6wind.com>
