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 1320F152DF4; Fri, 2 Feb 2024 18:39:34 +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=1706899175; cv=none; b=Ih/yB/6rURG9uMD8ji6oaSaZ/YH6LZyXHWgrhi4sUufYH3J7kKtjmsvHIiwaDnNx5sjIlNVlAfFP1al1kZYM/ZI4hrroSUkfSbcUuPQUcrk9y3ZdvkbKlLGjtBqmow8UA+VHyPym8dqaRBAk2plJojeuXxpGukaagMUwV2uUtPU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706899175; c=relaxed/simple; bh=94HCRGsnQQo8/820OUGWhKe+XapvGFDqMm0ejMc7aoU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=WN3apilRj8HuCoAK8EQB3SwODcT/YXE8iHSoArMPDt4qcmwGL0Y/gP/+7CJS3GGoXhnkPds2mEdfds59QmPV69hVvwqPixDED4Qlx1IuNoG2hnMq3Qs/laliNhUrFUanpkPf/O1RmQ470oQi5D+VlRQe6QuNbKhgf2XIL9VovHY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=QfunN7eV; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="QfunN7eV" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5EE57C43394; Fri, 2 Feb 2024 18:39:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1706899174; bh=94HCRGsnQQo8/820OUGWhKe+XapvGFDqMm0ejMc7aoU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QfunN7eV6jTw1ekJnV7FWnm8Us1v6bjjr0SACuzMw1hC2LHLfcRZREMOKBXCYVge0 uFAmyd7f2C0ZlaIfdrtJXYnqE9s7OnE9e/fJKC3cAEn2KX+skd2Do79ARBpx0Bp3oR ci62WGwpMztjs6/RxXJispjt2Y5ujTCIeoca0XEoPU7gqdab0MQX2U4GKLRN3aPF0v Xlwd0tg5xsJNmDLxPv6YPvtw7nJ32Ba0lgj3AxesR4s6U6jZDLetP1zwcE6qXWYt5F pks7kxkJl5RUsnT8aEwnhXrRqqczTilqafVtxgcJapjqiACX1fIDhn7doS7yU6Mh2R IWiKs8WHhqpHQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Fullway Wang , Helge Deller , Sasha Levin , tzimmermann@suse.de, sam@ravnborg.org, javierm@redhat.com, linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org Subject: [PATCH AUTOSEL 6.7 04/23] fbdev: sis: Error out if pixclock equals zero Date: Fri, 2 Feb 2024 13:39:00 -0500 Message-ID: <20240202183926.540467-4-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240202183926.540467-1-sashal@kernel.org> References: <20240202183926.540467-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.7.3 Content-Transfer-Encoding: 8bit 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 6ad47b6b6004..431b1a138c11 100644 --- a/drivers/video/fbdev/sis/sis_main.c +++ b/drivers/video/fbdev/sis/sis_main.c @@ -1475,6 +1475,8 @@ 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