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 EB3A313B2B8; Tue, 27 Feb 2024 14:01:54 +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=1709042515; cv=none; b=J4AvS492XrQKRvrK74p0jSfsvtkEtemmeNGJ09I1tnYzVyKV20nLM9T+GxxY/Oq39QVXZystsaQUy6MPoJC+i2hiKhHYlBbUJ75/Mci754DCrW4BaGQxszXZpwTRdjmlIqT+jYgVBkRhMX90j5bOLTmHcZFFF+Mg3qzjh1zTqxA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709042515; c=relaxed/simple; bh=tya4LxsV9uDs5dEHBAEEY5C49GOZDkUsh/ndyfPQy7g=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=XA7BrNCObleBY0IqKB2E6ZGUvfuctZcNnSVGwsrkzSlhBeQfU7R4i5Q6p0s2yO/0VrflsBvESTStoMjd05RtJxDGCGcMfZZQfh9em016K+oxD2c8pN21hDwR6qbpDQZYE/frBpPwtyzonmTRF1EJ8cMFwpIlWyw0QUngqXmYfsA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=hnfnpymh; 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="hnfnpymh" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7A0D1C433F1; Tue, 27 Feb 2024 14:01:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1709042514; bh=tya4LxsV9uDs5dEHBAEEY5C49GOZDkUsh/ndyfPQy7g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hnfnpymh6EBwD+GgKSj/c7wGTsHX781ukYKRUXdZkYjWDUoH3xrApX+HunZzaDlMz rJGu249D/EMPZL+6K6UByja0+/3mv/SrzB9OwKSv2rS8fasit2pGHgyw89RpfA5B+G irNAdG9XGacN8wzv4+U4vqbMBieSlA4v0cICNDjA= 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 5.15 023/245] fbdev: savage: Error out if pixclock equals zero Date: Tue, 27 Feb 2024 14:23:31 +0100 Message-ID: <20240227131615.870823935@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240227131615.098467438@linuxfoundation.org> References: <20240227131615.098467438@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 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Fullway Wang [ Upstream commit 04e5eac8f3ab2ff52fa191c187a46d4fdbc1e288 ] 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. Although pixclock is checked in savagefb_decode_var(), but it is not checked properly in savagefb_probe(). Fix this by checking whether pixclock is zero in the function savagefb_check_var() before info->var.pixclock is used as the divisor. 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/savage/savagefb_driver.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/video/fbdev/savage/savagefb_driver.c b/drivers/video/fbdev/savage/savagefb_driver.c index 0ac750cc5ea13..94ebd8af50cf7 100644 --- a/drivers/video/fbdev/savage/savagefb_driver.c +++ b/drivers/video/fbdev/savage/savagefb_driver.c @@ -868,6 +868,9 @@ static int savagefb_check_var(struct fb_var_screeninfo *var, DBG("savagefb_check_var"); + if (!var->pixclock) + return -EINVAL; + var->transp.offset = 0; var->transp.length = 0; switch (var->bits_per_pixel) { -- 2.43.0