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 1C5B9374A0C; Fri, 28 Aug 2026 16:14:07 +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=1787933648; cv=none; b=rjzjlnlFrCPCnqqkkYQVkTVPItWBkPof31jTP4AWOMh7VA/L51LTCsm9EOQL9mqtv/Quw4K40jo6lcPMi9ru8HAl9mS099AlPUKHwDE30Y3RwtsrS1sueXQvnScwcD8cwPyJ2iA3fQq/tqnkjV9zrPe0tDwnR29PktCqrqw8uEs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787933648; c=relaxed/simple; bh=OI1gnMNlvOgrvAGGV2Cm5sMcmuSRCXQ1XJJXH6CRrO8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Yx+URF79Omcbabkd1LvJxYLjHtf1kMDvu1Bkju0Fjk5qDlPwpGd1WgmA2YextXFNF7TGErzCmfc5ttvoOJwiEYX6BrPQqSaFqbX+Lb36AUvUavFBSTGqPtAIImiSqi0q/qnWCI2BqPeHdzuJn0ck+/svoA4A7XUU5g6EKH+gErw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=d1Ebrr4G; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="d1Ebrr4G" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5E7F51F000E9; Fri, 28 Aug 2026 16:14:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1787933647; bh=lVZVYg+bDdK1zVHqn8k5MSf2PwzC871N3x+gQ/FCclE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=d1Ebrr4Gr3uRXuLIyvSiM/awqnfTJZFvwWzfvneayBDm/mkzw+AK4G7M3mAjBgqyH wkdV5WiiqEVPEn69UxRfXBAyOcZolZfPSc29dGhSCUScInNRKj5+J7FOh0l8xaZLuD VPnF9wpo13SrZRhohjKHZjueqHohCghXsc6mGCtF5BkGv68zlHZ1KJ0uBSwBpjABky GFqja39xzFHdUq2h2IDRnOz5oq5Xt99Gu83h+Wwm73bYptI7S1DVqJtBQwhZ0xQzJm U513gDXZG1j7KD6lMzGVS0LKZswknwwNGtvkrxfm/xxZlhAsrTRGEhyIqCpwkTJF1n HQGgzf0bhTM4Q== From: Tzung-Bi Shih To: Wim Van Sebroeck , Guenter Roeck Cc: Daniel Palmer , Romain Perier , linux-watchdog@vger.kernel.org, linux-kernel@vger.kernel.org, tzungbi@kernel.org Subject: [PATCH v2 2/9] watchdog: msc313e: Avoid division by zero Date: Sat, 29 Aug 2026 00:13:41 +0800 Message-ID: <20260828161348.13212-3-tzungbi@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260828161348.13212-1-tzungbi@kernel.org> References: <20260828161348.13212-1-tzungbi@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit clk_get_rate() could return 0. Avoid a division by zero panic. Fixes: e9800b799464 ("watchdog: Add Mstar MSC313e WDT driver") Signed-off-by: Tzung-Bi Shih --- Simply browsed code under drivers/watchdog/, the following drivers also use clk_get_rate() as a denominator directly: - drivers/watchdog/digicolor_wdt.c - drivers/watchdog/rtd119x_wdt.c - drivers/watchdog/rzv2h_wdt.c Let me know if you think we should fix them as well. --- v2: - New to the series. --- drivers/watchdog/msc313e_wdt.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/watchdog/msc313e_wdt.c b/drivers/watchdog/msc313e_wdt.c index f69d66971c41..c3018b970164 100644 --- a/drivers/watchdog/msc313e_wdt.c +++ b/drivers/watchdog/msc313e_wdt.c @@ -97,6 +97,7 @@ static int msc313e_wdt_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct msc313e_wdt_priv *priv; + unsigned long rate; priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); if (!priv) @@ -116,7 +117,10 @@ static int msc313e_wdt_probe(struct platform_device *pdev) priv->wdev.ops = &msc313e_wdt_ops, priv->wdev.parent = dev; priv->wdev.min_timeout = MSC313E_WDT_MIN_TIMEOUT; - priv->wdev.max_timeout = U32_MAX / clk_get_rate(priv->clk); + rate = clk_get_rate(priv->clk); + if (!rate) + return -EINVAL; + priv->wdev.max_timeout = U32_MAX / rate; priv->wdev.timeout = MSC313E_WDT_DEFAULT_TIMEOUT; /* If the period is non-zero the WDT is running */ -- 2.53.0