From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DCF5941B8CA; Thu, 30 Jul 2026 15:01:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785423702; cv=none; b=fGHIxThwtJn0g5XC8KF7I8lEl1yZIkMUIoXq7yhKaOTh3BrpJ21G+emnBcf7vssgXJDMyzC6ysBZRRnCAxxeVjhJx3JOjGpwz3mHOyf7TH19O4sYcGzuPNTZnBu53ce9El0nd43p4/DDLSEECnNGb/bAynQT4PVQcUJY4CR09tw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785423702; c=relaxed/simple; bh=voQKxJBdzKrfT5ovRsSh+soNHZrV7lkS1WrXAxrA+3c=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=pwUiLDm2PHVUAu1YPcXVVelIdI6wnNzZujsQqi8JGcyDy04EZ0+W1VxQ7j6VBFlcxI90FFwtZq3cJWJw4XuZD34B9HTXmbDTBb4k20VClvPZWqOIgt0MQrtH+Yyu8JYocQ2s34Kf7wvJGhMXt+7Ehksiu00Fw/AT80yUCbFKiPo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=iF7p3FyD; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="iF7p3FyD" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 376681F000E9; Thu, 30 Jul 2026 15:01:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1785423700; bh=QSvw/PsknDZcTStz5IOvsEdVVQqyFWbleo2+Borq1og=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=iF7p3FyDV5pYIuE8nwvTOnhkvFQujXOcHmCht21yVsVBEKeg2iMiLasZ8c6q2zdn6 2yYF2dxNOC3ZmZFXQSw/DcbQ8TiUmUSEMtn49/IY++EgbvO8zyRfmmsofycLr96D2o FeEKPJybM6Xl8Rgny42odaDEwif2wT7Sd/7cQDZE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yuan Tan , Xin Liu , Zihan Xi , Ren Wei , Xin Long , Paolo Abeni , Sasha Levin Subject: [PATCH 6.18 137/675] sctp: fix auth_hmacs array size in struct sctp_cookie Date: Thu, 30 Jul 2026 16:07:47 +0200 Message-ID: <20260730141448.050197018@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260730141445.110192266@linuxfoundation.org> References: <20260730141445.110192266@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Xin Long [ Upstream commit e0b5252a59383b77d1b8dbeda00b7184dd95f4d3 ] The auth_hmacs array in struct sctp_cookie is supposed to store a complete SCTP_AUTH_HMAC_ALGO parameter, which consists of a struct sctp_paramhdr followed by N HMAC identifiers. However, the array size was calculated using an extra 2 bytes instead of sizeof(struct sctp_paramhdr), which is 4 bytes. When four HMAC identifiers are configured, the HMAC-ALGO parameter stored in the endpoint is larger than the auth_hmacs buffer in the cookie. As a result, sctp_association_init() copies beyond the end of auth_hmacs when initializing the association, corrupting the adjacent auth_chunks field. This can lead to an invalid HMAC identifier being accepted and later cause an out-of-bounds read in sctp_auth_get_hmac(). Fix the array size calculation by including the full SCTP parameter header size. Fixes: 1f485649f529 ("[SCTP]: Implement SCTP-AUTH internals") Reported-by: Yuan Tan Reported-by: Xin Liu Reported-by: Zihan Xi Reported-by: Ren Wei Signed-off-by: Xin Long Link: https://patch.msgid.link/634a0de0d5de29532915e6d47c92a0cbc206e03f.1783707155.git.lucien.xin@gmail.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- include/net/sctp/structs.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h index 2ae390219efdd3..4bbba29f7341ee 100644 --- a/include/net/sctp/structs.h +++ b/include/net/sctp/structs.h @@ -316,7 +316,8 @@ struct sctp_cookie { __u8 auth_random[sizeof(struct sctp_paramhdr) + SCTP_AUTH_RANDOM_LENGTH]; - __u8 auth_hmacs[SCTP_AUTH_NUM_HMACS * sizeof(__u16) + 2]; + __u8 auth_hmacs[sizeof(struct sctp_paramhdr) + + SCTP_AUTH_NUM_HMACS * sizeof(__u16)]; __u8 auth_chunks[sizeof(struct sctp_paramhdr) + SCTP_AUTH_MAX_CHUNKS]; /* This is a shim for my peer's INIT packet, followed by -- 2.53.0