4.14-stable review patch. If anyone has any objections, please let me know.
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From: Mathieu Xhonneux m.xhonneux@gmail.com
[ 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 dlebrun@google.com Signed-off-by: Mathieu Xhonneux m.xhonneux@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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;