Re: [syzbot] [mptcp?] KMSAN: uninit-value in mptcp_incoming_options

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Subject: [mptcp?] KMSAN: uninit-value in mptcp_incoming_options
Author: eadavis@qq.com

please test uninit-value in mptcp_incoming_options

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git c2d5304e6c64

diff --git a/net/mptcp/options.c b/net/mptcp/options.c
index cd15ec73073e..c53914012d01 100644
--- a/net/mptcp/options.c
+++ b/net/mptcp/options.c
@@ -108,6 +108,7 @@ static void mptcp_parse_option(const struct sk_buff *skb,
 			mp_opt->suboptions |= OPTION_MPTCP_DSS;
 			mp_opt->use_map = 1;
 			mp_opt->mpc_map = 1;
+			mp_opt->use_ack = 0;
 			mp_opt->data_len = get_unaligned_be16(ptr);
 			ptr += 2;
 		}