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 D26383624CC; Sat, 12 Sep 2026 18:19:48 +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=1789237189; cv=none; b=t0fmJyntacLxXbMfKDcrFFXGWIDif6x9pnOSkDiuI6SK2pCKZhYCMw/pxZ4+jC1zPZDr0QXwiwZGOaRzgEUh3VFPmsHfoY1G5chk5xXPvrt0GoLKL38Vso3ahJ4Oazl7HziHV4+Mu+T84a27xC0TQY2QuIExQzg5NqVXmCq+NPA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789237189; c=relaxed/simple; bh=hEhV8HFmnPIRYrqnsa0+0StpCjUnIrXrkp0xtdyW0cE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DUmKaJA+SCOP5iilpY75kv5i5YJYE18zlCsMuGLBOo9IoVe2JCqLgazJwdRYgd8Upud2Bo8JXsm42ruM3hKO7nm0ZuV3DjI/lDt9t4YfyWJAM0b3k02j9vP0AU8cY4lqAYJy8iY+VFtZDN1QQRRODDjvYr6FKrlJUw9zo5WG4p0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=XxycNlXe; 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="XxycNlXe" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 741F31F000FF; Sat, 12 Sep 2026 18:19:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789237188; bh=23D7fjLjeyuxJiPFK77Oy1HwYUPDWZQ5MRGjawi21o4=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=XxycNlXeOd/BQrm9dNXgRfz4vAy2oQR0X1CTZVGbmSxOHiD5dcBDiMRR79z0Ki/8l qIiqP8jncbWfmzub1XvUBGW8EELuuVGnmQih60YGvwAxqWYgFlhTtwaNJ8LCmwNb5b iMWac2HtPVFm2DzI3ApD/ERuAMpa4JrvKLT22xno= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yousef Alhouseen , Corey Minyard Subject: [PATCH 5.15 171/935] ipmi: ipmb: validate write message length Date: Sat, 12 Sep 2026 08:53:21 +0200 Message-ID: <20260912065530.740087794@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065526.833703348@linuxfoundation.org> References: <20260912065526.833703348@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 5.15-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]);