From 8e60eed6b38e464e8c9d68f9caecafaa554dffe0 Mon Sep 17 00:00:00 2001 From: Geliang Tang Date: Mon, 8 Jun 2020 18:47:54 +0800 Subject: mptcp: bugfix for RM_ADDR option parsing In MPTCPOPT_RM_ADDR option parsing, the pointer "ptr" pointed to the "Subtype" octet, the pointer "ptr+1" pointed to the "Address ID" octet: +-------+-------+---------------+ |Subtype|(resvd)| Address ID | +-------+-------+---------------+ | | ptr ptr+1 We should set mp_opt->rm_id to the value of "ptr+1", not "ptr". This patch will fix this bug. Fixes: 3df523ab582c ("mptcp: Add ADD_ADDR handling") Signed-off-by: Geliang Tang Reviewed-by: Matthieu Baerts Signed-off-by: David S. Miller --- net/mptcp/options.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'net') diff --git a/net/mptcp/options.c b/net/mptcp/options.c index 01f1f4cf4902..490b92534afc 100644 --- a/net/mptcp/options.c +++ b/net/mptcp/options.c @@ -273,6 +273,8 @@ static void mptcp_parse_option(const struct sk_buff *skb, if (opsize != TCPOLEN_MPTCP_RM_ADDR_BASE) break; + ptr++; + mp_opt->rm_addr = 1; mp_opt->rm_id = *ptr++; pr_debug("RM_ADDR: id=%d", mp_opt->rm_id); -- cgit