netdev - [PATCH net v2] sctp: Prevent TOCTOU out-of-bounds write

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <20251027101328.2312025-2-stefan.wiehler@nokia.com>
Date: Mon, 27 Oct 2025 11:13:29 +0100
From: Stefan Wiehler <stefan.wiehler@...ia.com>
To: Xin Long <lucien.xin@...il.com>,
	"David S . Miller " <davem@...emloft.net>,
	Eric Dumazet <edumazet@...gle.com>,
	Jakub Kicinski <kuba@...nel.org>,
	Paolo Abeni <pabeni@...hat.com>,
	Simon Horman <horms@...nel.org>,
	Kuniyuki Iwashima <kuniyu@...gle.com>
Cc: linux-sctp@...r.kernel.org,
	netdev@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Stefan Wiehler <stefan.wiehler@...ia.com>
Subject: [PATCH net v2] sctp: Prevent TOCTOU out-of-bounds write

Make sure not to exceed bounds in case the address list has grown
between buffer allocation (time-of-check) and write (time-of-use).

Suggested-by: Kuniyuki Iwashima <kuniyu@...gle.com>
Fixes: 8f840e47f190 ("sctp: add the sctp_diag.c file")
Signed-off-by: Stefan Wiehler <stefan.wiehler@...ia.com>
---
V1 -> V2: Add changelog and credit
---
 net/sctp/diag.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/sctp/diag.c b/net/sctp/diag.c
index 996c2018f0e6..4ee44e0111ae 100644
--- a/net/sctp/diag.c
+++ b/net/sctp/diag.c
@@ -85,6 +85,9 @@ static int inet_diag_msg_sctpladdrs_fill(struct sk_buff *skb,
 		memcpy(info, &laddr->a, sizeof(laddr->a));
 		memset(info + sizeof(laddr->a), 0, addrlen - sizeof(laddr->a));
 		info += addrlen;
+
+		if (!--addrcnt)
+			break;
 	}
 
 	return 0;
-- 
2.51.0