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 0FDFC315785; Sat, 12 Sep 2026 13:46:46 +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=1789220809; cv=none; b=U0NYcPiNTVE0sBMdgKgvtuRhOOUhk9dXNwr+u7Ep0ChF5ExiLJc08f0MDYFkhLto0fQYqS5sg5AMh412euiVDNOgJHoM9fYwdIjOGd+G/3wcSJrDVcxKA9QGNjX+49lBi8KWH9H9x5h+gBtfRVVksRUYknBv0RlfTK2S7EEsfl0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789220809; c=relaxed/simple; bh=aZur4STV+0Sakhbx5tTE3+m4otcgBrUhQvDRzt7BhyQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=dGun6dn9vezVIZVz+pdcyFB9Y1Z3xTmLmiSWhENMZj4p0KqILVyvudY/J/cMq9mGf/u/1P6tJKQZ7OIPElgRmmgYuRH83wUiIrMhkDIwhaTLPdRUh6CzDaqWASPlon4BeuVk1BkpcTLggMgtI8Eaz32QgRLwONo/9CgzfsCozfo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=AMR8ykjP; 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="AMR8ykjP" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 69E231F000FF; Sat, 12 Sep 2026 13:46:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789220806; bh=puaV6d83zrDC1zX9eAOLQV8uAqx2yEKVvb9VJQr7HE8=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=AMR8ykjPucczq3yam4FIw/5GzYFaGggxdqjUG6iZEY2/4InWErSt6DHt7etdPA4R3 X1wrCIeJ+UmmphPiPSGPxwFMGEyoqtn8JwJTDAcfTHO5ylWKymaOHr/ItELIkGV3hY ZDA1iekg5PrJq1g2MrV5vsCfnxW9fzFW6zOaWGMw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yousef Alhouseen , Corey Minyard Subject: [PATCH 6.6 0251/1424] ipmi: ipmb: validate write message length Date: Sat, 12 Sep 2026 08:44:43 +0200 Message-ID: <20260912065612.900015140@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065607.279695368@linuxfoundation.org> References: <20260912065607.279695368@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 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yousef Alhouseen commit 53637506884dbd5c91a89b1a3547d99d80f8ed2c upstream. ipmb_write() read message fields before validating the length byte. A zero or short write can read uninitialized stack bytes. A length smaller than the SMBus header underflows the block write length. Require a non-empty buffer and the minimum IPMB request length. Also require the length byte plus payload before parsing the message. Fixes: 51bd6f291583 ("Add support for IPMB driver") Cc: stable@vger.kernel.org Signed-off-by: Yousef Alhouseen Message-ID: <20260624175353.8592-1-alhouseenyousef@gmail.com> Signed-off-by: Corey Minyard Signed-off-by: Greg Kroah-Hartman --- drivers/char/ipmi/ipmb_dev_int.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/drivers/char/ipmi/ipmb_dev_int.c +++ b/drivers/char/ipmi/ipmb_dev_int.c @@ -141,13 +141,14 @@ static ssize_t ipmb_write(struct file *f u8 msg[MAX_MSG_LEN]; ssize_t ret; - if (count > sizeof(msg)) + if (!count || count > sizeof(msg)) return -EINVAL; if (copy_from_user(&msg, buf, count)) return -EFAULT; - if (count < msg[0]) + if (msg[IPMB_MSG_LEN_IDX] < IPMB_REQUEST_LEN_MIN || + count < (size_t)msg[IPMB_MSG_LEN_IDX] + 1) return -EINVAL; rq_sa = GET_7BIT_ADDR(msg[RQ_SA_8BIT_IDX]);