From 4029820677b267cb0a04b5a0b34ecb191b960f88 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 11 Jan 2024 19:49:13 +0000 Subject: [PATCH] mptcp: mptcp_parse_option() fix for MPTCPOPT_MP_JOIN [ Upstream commit 89e23277f9c16df6f9f9c1a1a07f8f132339c15c ] mptcp_parse_option() currently sets OPTIONS_MPTCP_MPJ, for the three possible cases handled for MPTCPOPT_MP_JOIN option. OPTIONS_MPTCP_MPJ is the combination of three flags: - OPTION_MPTCP_MPJ_SYN - OPTION_MPTCP_MPJ_SYNACK - OPTION_MPTCP_MPJ_ACK This is a problem, because backup, join_id, token, nonce and/or hmac fields could be left uninitialized in some cases. Distinguish the three cases, as following patches will need this step. Fixes: f296234c98a8 ("mptcp: Add handling of incoming MP_JOIN requests") Signed-off-by: Eric Dumazet Cc: Florian Westphal Cc: Peter Krystad Cc: Matthieu Baerts Cc: Mat Martineau Cc: Geliang Tang Reviewed-by: Simon Horman Acked-by: Paolo Abeni Reviewed-by: Mat Martineau Link: https://lore.kernel.org/r/20240111194917.4044654-2-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/mptcp/options.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/net/mptcp/options.c b/net/mptcp/options.c index c539140..d2527d1 100644 --- a/net/mptcp/options.c +++ b/net/mptcp/options.c @@ -123,8 +123,8 @@ static void mptcp_parse_option(const struct sk_buff *skb, break; case MPTCPOPT_MP_JOIN: - mp_opt->suboptions |= OPTIONS_MPTCP_MPJ; if (opsize == TCPOLEN_MPTCP_MPJ_SYN) { + mp_opt->suboptions |= OPTION_MPTCP_MPJ_SYN; mp_opt->backup = *ptr++ & MPTCPOPT_BACKUP; mp_opt->join_id = *ptr++; mp_opt->token = get_unaligned_be32(ptr); @@ -135,6 +135,7 @@ static void mptcp_parse_option(const struct sk_buff *skb, mp_opt->backup, mp_opt->join_id, mp_opt->token, mp_opt->nonce); } else if (opsize == TCPOLEN_MPTCP_MPJ_SYNACK) { + mp_opt->suboptions |= OPTION_MPTCP_MPJ_SYNACK; mp_opt->backup = *ptr++ & MPTCPOPT_BACKUP; mp_opt->join_id = *ptr++; mp_opt->thmac = get_unaligned_be64(ptr); @@ -145,11 +146,10 @@ static void mptcp_parse_option(const struct sk_buff *skb, mp_opt->backup, mp_opt->join_id, mp_opt->thmac, mp_opt->nonce); } else if (opsize == TCPOLEN_MPTCP_MPJ_ACK) { + mp_opt->suboptions |= OPTION_MPTCP_MPJ_ACK; ptr += 2; memcpy(mp_opt->hmac, ptr, MPTCPOPT_HMAC_LEN); pr_debug("MP_JOIN hmac"); - } else { - mp_opt->suboptions &= ~OPTIONS_MPTCP_MPJ; } break; -- 2.7.4