From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 9FE0C13B2B8; Tue, 27 Feb 2024 14:22:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709043735; cv=none; b=lY7Q10AxdA3oE3krbgf09kJNOagWpzT5ZnLx1lvjaxiSuv9vqLXuDFjzIAJSTrmVLbc6Gn8LLcvYm0Jp1FkWS0e/j4xNuSLR3tQ6fdyCZCJj3Sn9RDVVEvQ2HAVHRmyjcThJGmC9Cipp9Iic4gfA+hMfqlHy8J3P80x6+hE5Ywo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709043735; c=relaxed/simple; bh=R8JKXIlHkwuDze/yhoLPH8p0qmX3ZrVf9wJLBN9q3Ro=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ZusFbl1xi9PlOpxuAKpvcIlLDrmRSbP/BxMaum6zSq+/+PfDxW8bpbkVGiZU2kOjh7X4dUUuKTj0KyRL0HxZE9tEw3MnUVUtiEptBAyeCeX7uIgW//v5sAnPO2wJwUp9HTi0GVtFt8OXqMvk139MrI1eNKml0Hqq0aRvf32YHyE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ztqZltJ6; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="ztqZltJ6" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CDE63C433C7; Tue, 27 Feb 2024 14:22:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1709043735; bh=R8JKXIlHkwuDze/yhoLPH8p0qmX3ZrVf9wJLBN9q3Ro=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ztqZltJ6Omd17Q1bWQF5i/+O2X8ySZDOkHf+eio1ODnPGRI/o0tTQX6gEkSdzVTZE xVLZy1/aqoD/rgESPTcBgE2vdV+owMYtWpbEU/py20l9gMROoY2i0oeXlypF/nNSw3 Uu/gta5s6jfACSXrwST5L27GSOFM4VSvPwhMjVB4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Fullway Wang , Helge Deller , Sasha Levin Subject: [PATCH 5.4 18/84] fbdev: sis: Error out if pixclock equals zero Date: Tue, 27 Feb 2024 14:26:45 +0100 Message-ID: <20240227131553.463289149@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240227131552.864701583@linuxfoundation.org> References: <20240227131552.864701583@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Fullway Wang [ Upstream commit e421946be7d9bf545147bea8419ef8239cb7ca52 ] The userspace program could pass any values to the driver through ioctl() interface. If the driver doesn't check the value of pixclock, it may cause divide-by-zero error. In sisfb_check_var(), var->pixclock is used as a divisor to caculate drate before it is checked against zero. Fix this by checking it at the beginning. This is similar to CVE-2022-3061 in i740fb which was fixed by commit 15cf0b8. Signed-off-by: Fullway Wang Signed-off-by: Helge Deller Signed-off-by: Sasha Levin --- drivers/video/fbdev/sis/sis_main.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/video/fbdev/sis/sis_main.c b/drivers/video/fbdev/sis/sis_main.c index b443a8ed46003..2fdd02e51f5fc 100644 --- a/drivers/video/fbdev/sis/sis_main.c +++ b/drivers/video/fbdev/sis/sis_main.c @@ -1474,6 +1474,8 @@ sisfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info) vtotal = var->upper_margin + var->lower_margin + var->vsync_len; + if (!var->pixclock) + return -EINVAL; pixclock = var->pixclock; if((var->vmode & FB_VMODE_MASK) == FB_VMODE_NONINTERLACED) { -- 2.43.0