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 526C033262B; Mon, 20 Apr 2026 15:46:23 +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=1776699983; cv=none; b=LuDbDY9bT9Tff3k+sHBl4SRU0OKtS7Qiv4/6zxBalfWGm6Hq4qW7zuRysdsmpyPhbgDMGKseAqlL1Fs6SvPwnkVPRJU93YbFWKKbHn7lj2t9WeQq7x1E6pEmXTGsZAPXbJz4jGD76R0yVx9VXRftQ2fvf0JqsRe0DM4UndGoBJI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776699983; c=relaxed/simple; bh=2TT3lJ4PTIbCBGJ2VA4Nujm5eHgW9f9uclXRQi/EI2c=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=FQUQupJL0Iio8U+72UfVFMQ8QEkElgRxnIPy/3p4sDZMdivyKdrZrknh8fjz5O2xFohPobtnfrPaykkbTY6gRmXsaDH3qMa9MWdSQpHfGlI0ld2rZC8+MaIkCJV3McntFUSavCcz/E5i6dA9VMOrvPDJhAeN6DjXSTO4KwQrKF0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=hClQZnDJ; 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="hClQZnDJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DD9CFC19425; Mon, 20 Apr 2026 15:46:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1776699983; bh=2TT3lJ4PTIbCBGJ2VA4Nujm5eHgW9f9uclXRQi/EI2c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hClQZnDJC0878n40c4LDivpIhSD+wTWRZEN3Ugs+ckUPnm0HdOSQDpRyEWNkwZNMw EcTc+NDEKOLT3NzVFnwTliar1XJLwrqBsbj0aGM4+0FpN63BKNSAzxGmlDK06sIG7M ptJKZ8/ZQRSPO9BuhkAHjgGVhKy06maXMmTJ8/R8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Bernie Thompson , Helge Deller Subject: [PATCH 7.0 31/76] fbdev: udlfb: avoid divide-by-zero on FBIOPUT_VSCREENINFO Date: Mon, 20 Apr 2026 17:41:42 +0200 Message-ID: <20260420153911.955256631@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260420153910.810034134@linuxfoundation.org> References: <20260420153910.810034134@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 7.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Greg Kroah-Hartman commit a31e4518bec70333a0a98f2946a12b53b45fe5b9 upstream. Much like commit 19f953e74356 ("fbdev: fb_pm2fb: Avoid potential divide by zero error"), we also need to prevent that same crash from happening in the udlfb driver as it uses pixclock directly when dividing, which will crash. Cc: Bernie Thompson Cc: Helge Deller Fixes: 59277b679f8b ("Staging: udlfb: add dynamic modeset support") Assisted-by: gregkh_clanker_t1000 Signed-off-by: Greg Kroah-Hartman Signed-off-by: Helge Deller Signed-off-by: Greg Kroah-Hartman --- drivers/video/fbdev/udlfb.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/video/fbdev/udlfb.c +++ b/drivers/video/fbdev/udlfb.c @@ -1018,6 +1018,9 @@ static int dlfb_ops_check_var(struct fb_ struct fb_videomode mode; struct dlfb_data *dlfb = info->par; + if (!var->pixclock) + return -EINVAL; + /* set device-specific elements of var unrelated to mode */ dlfb_var_color_format(var);