4.14-stable review patch. If anyone has any objections, please let me know.
------------------ From: Mathieu Xhonneux <[email protected]> [ Upstream commit ccc12b11c5332c84442ef120dcd631523be75089 ] Function ipv6_push_rthdr4 allows to add an IPv6 Segment Routing Header to a socket through setsockopt, but the current implementation doesn't copy possible TLVs at the end of the SRH received from userspace. Therefore, the execution of the following branch if (sr_has_hmac(sr_phdr)) { ... } will never complete since the len and type fields of a possible HMAC TLV are not copied, hence seg6_get_tlv_hmac will return an error, and the HMAC will not be computed. This commit adds a memcpy in case TLVs have been appended to the SRH. Fixes: a149e7c7ce81 ("ipv6: sr: add support for SRH injection through setsockopt") Acked-by: David Lebrun <[email protected]> Signed-off-by: Mathieu Xhonneux <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- net/ipv6/exthdrs.c | 9 +++++++++ 1 file changed, 9 insertions(+) --- a/net/ipv6/exthdrs.c +++ b/net/ipv6/exthdrs.c @@ -884,6 +884,15 @@ static void ipv6_push_rthdr4(struct sk_b sr_phdr->segments[0] = **addr_p; *addr_p = &sr_ihdr->segments[sr_ihdr->segments_left]; + if (sr_ihdr->hdrlen > hops * 2) { + int tlvs_offset, tlvs_length; + + tlvs_offset = (1 + hops * 2) << 3; + tlvs_length = (sr_ihdr->hdrlen - hops * 2) << 3; + memcpy((char *)sr_phdr + tlvs_offset, + (char *)sr_ihdr + tlvs_offset, tlvs_length); + } + #ifdef CONFIG_IPV6_SEG6_HMAC if (sr_has_hmac(sr_phdr)) { struct net *net = NULL;
