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 0E06637F30A; Fri, 28 Aug 2026 16:14:14 +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=1787933656; cv=none; b=L7seZ5JT4NBxs7xZODl+GJgRx555Y1eW5T36yxPDoymjvuhKvCXALeqyrWIYGoH63w36xRjrCixsTkZEXxwMmOTdrkPWhzhXdob9DyVaDEHFDQh6FszyF3AZE2fJm36ih/xYwsuFgVcOTvOu+szzNvpSShRTujEIeG/5fr0BAQY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787933656; c=relaxed/simple; bh=CzNXetXzMpV5laXvu1UZuBL1MVCgiPCImOmLppOahzw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=SnhFeTNpp3lwiA0SHH2airIRxTTjUAgzB8vT4W8GAPMcLqzi/oMyR39WZdjYPLCqK0ISIzXSLYE7u13UTkNGsUB9XMo7ZALp0qhMPo9DMHMGtIsN6kGyeZ36fo2k0KNuUeWL/lQ+bdkJ7cLIqtQ9sTDgDy8OzrjHY1UVErdXplk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=kCh16YUq; 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="kCh16YUq" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 54B9E1F000E9; Fri, 28 Aug 2026 16:14:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1787933654; bh=yyE0NU9jUPYovPGQZ2kNJN+/27g7SBh3xX6czLk4DQc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=kCh16YUqWtR0nDpTCNgGe4aC4V96Yo0m6sd7o6aDUP/xDdPdg/SDbdiW+I6zo5xfb 6sl/2msranaaqzGKsP25j+eR+umf/5dzB32vBg78LJOGmnU3dW8ZVHqQ8RQpn23J4Q QtEmPyjhufVYkduRvP4vHC8TBRr9Gi7yyvA9TiJaxyV4ZaQhFOfBA2ZYPOjyfKXo+g e6ZhLc3uQz8lUzwnlpuKd+mXFwzTAaWESdG0+epIFScvaQKEfBzM/uGpGgq0Hp0cZr KfZAArWfyh/cSbXL4xVdq3Y+G+S7SLysM3tHRMJNjmkIgPRk5Ahjbsl6NlfADANRbs ywJ7Quz6NsTDA== 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 6/9] watchdog: msc313e: Fix undefined behavior Date: Sat, 29 Aug 2026 00:13:45 +0800 Message-ID: <20260828161348.13212-7-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 readw() returns a u16. Left shifting a u16 by 16 bits yields undefined behavior. Cast to u32 explicitly before the shift. Fixes: ffd264bd152c ("watchdog: msc313e: Check if the WDT was running at boot") Signed-off-by: Tzung-Bi Shih --- v2: - New to the series. --- drivers/watchdog/msc313e_wdt.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/watchdog/msc313e_wdt.c b/drivers/watchdog/msc313e_wdt.c index c7d558fefc86..e28261c7a8d4 100644 --- a/drivers/watchdog/msc313e_wdt.c +++ b/drivers/watchdog/msc313e_wdt.c @@ -31,6 +31,16 @@ struct msc313e_wdt_priv { struct clk *clk; }; +static u32 msc313e_wdt_get_hw_timeout(struct msc313e_wdt_priv *priv) +{ + u16 low, high; + + low = readw(priv->base + REG_WDT_MAX_PRD_L); + high = readw(priv->base + REG_WDT_MAX_PRD_H); + + return ((u32)high << 16) | low; +} + static void msc313e_wdt_set_hw_timeout(struct msc313e_wdt_priv *priv, unsigned int timeout) { @@ -139,7 +149,7 @@ static int msc313e_wdt_probe(struct platform_device *pdev) return ret; /* If the period is non-zero the WDT is running */ - if (readw(priv->base + REG_WDT_MAX_PRD_L) | (readw(priv->base + REG_WDT_MAX_PRD_H) << 16)) { + if (msc313e_wdt_get_hw_timeout(priv)) { set_bit(WDOG_HW_RUNNING, &priv->wdev.status); /* * Keep the clock enabled. The watchdog core will skip the next -- 2.53.0