[PATCH AUTOSEL 6.12 090/107] mptcp: fix possible integer overflow in mptcp_reset_tout_timer

[Sasha Levin]

From: Dmitry Kandybka <d.kandybka@xxxxxxxxx>

[ Upstream commit b169e76ebad22cbd055101ee5aa1a7bed0e66606 ]

In 'mptcp_reset_tout_timer', promote 'probe_timestamp' to unsigned long
to avoid possible integer overflow. Compile tested only.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Signed-off-by: Dmitry Kandybka <d.kandybka@xxxxxxxxx>
Link: https://patch.msgid.link/20241107103657.1560536-1-d.kandybka@xxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 net/mptcp/protocol.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index 47ee616f69c2d..8a8e8fee337f5 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -2728,8 +2728,8 @@ void mptcp_reset_tout_timer(struct mptcp_sock *msk, unsigned long fail_tout)
 	if (!fail_tout && !inet_csk(sk)->icsk_mtup.probe_timestamp)
 		return;
 
-	close_timeout = inet_csk(sk)->icsk_mtup.probe_timestamp - tcp_jiffies32 + jiffies +
-			mptcp_close_timeout(sk);
+	close_timeout = (unsigned long)inet_csk(sk)->icsk_mtup.probe_timestamp -
+			tcp_jiffies32 + jiffies + mptcp_close_timeout(sk);
 
 	/* the close timeout takes precedence on the fail one, and here at least one of
 	 * them is active
-- 
2.43.0