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 66ED6219303; Sat, 30 May 2026 18:22:50 +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=1780165371; cv=none; b=aEFXlAlzhKeDq06u+vDZs0LthcKbo8EOoOeqvNSp5OQhYJ5P/8qyuXTprS4v5YMjrtJYvgO3g1iLRAlUI5YFmwDYEWw+NDHns5fCKkYDKEC+TqXaMQrTZak56IpxvaVKGtIGJZk0FAwQmEII5IwGv4Pde4VUZSkxVcEJmPq8Lww= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780165371; c=relaxed/simple; bh=lLq74fo+f5yiHeEczv2joNCOyTulueAAh1qThQpHsv0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=sZszlPQvb78rZLTeBKmgvzqxd5vwcmJo4H0B+naHcaMTNsAwQSJZ4ne8Pwaj1dvKGFY2r7GVc4CJcpPWISTo126y6RtMYMr4XbZ2DpigoYtRM7NVRPACEry7acMsw0bgprRnvCJf7O1KN/3Gy6GZHu600PyL/vLWqSU6Xfc+e0A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=uuahXpS4; 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="uuahXpS4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AC1BE1F00893; Sat, 30 May 2026 18:22:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1780165370; bh=MGHthj33QWYO/Ed0j/htjXUZ0dCNheiCHf/4Wj0Gsg8=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=uuahXpS4c/6iIEiJLZUYL0j+m+V8C8na8meUmUUjw6lKkyV1slIr2rJAGscPgR5o3 dqFqF0pxgiqHdxT2z9v47bOT7Mp/kzmUGC8sJg6nMumBNN0u93f9zcmzMqrw1Xbs6k hd+hiZ/49ikwkRWruXZJX5Ur3h/eh5WvHgBja/Sk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Bernie Thompson , Helge Deller Subject: [PATCH 5.10 058/589] fbdev: udlfb: avoid divide-by-zero on FBIOPUT_VSCREENINFO Date: Sat, 30 May 2026 17:58:59 +0200 Message-ID: <20260530160226.120538464@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260530160224.570625122@linuxfoundation.org> References: <20260530160224.570625122@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 5.10-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 @@ -1077,6 +1077,9 @@ 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);