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 D2FCF14A08A; Mon, 22 Jan 2024 15:17:31 +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=1705936651; cv=none; b=D+AUDX29pbjAU1uko7bf+9+8PJ9Dx0qXWEDHkwUQB3DPNZI4sWUtEZsJzEOMkt5begEzPzAeftsova3CXVWEU4nwTBeI0YtZQ5M/BAoqjlXbvdy4kK3LUmteMzNXU59V3rG4b+H5cqznO/+Eqcxq5PR1N8T6Z/vsjt3nGXW1uu0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705936651; c=relaxed/simple; bh=i5bEYdSRw06a6/t8+Y9FAvU0Xv7Oumy6T+7uuOFPK4I=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=uEInI26riAwB/Te7+igZn3dAJzKwr/LKXw09Q9JVT6z8pJap2AS8qSPchN3twqciLVlIikSDJmvZkBs8I9Z5M+6ptHNXb/92RmnG0lNBzBrfOzWmGir5kh2+8mMsbUYgAFB/dD35YA/YLKPfDHobkft5hIWrfdScxQAFpQ2aSXU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=HCaSEXBw; 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="HCaSEXBw" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8D6D3C433C7; Mon, 22 Jan 2024 15:17:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1705936651; bh=i5bEYdSRw06a6/t8+Y9FAvU0Xv7Oumy6T+7uuOFPK4I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HCaSEXBw/alC/JmWpi71I6tO6bR8mY+vPzVM8jPyYwgSIKt2Tv2jHuFxYwtibFW77 rhh2V+umdUMYZKlzRZZ8nBa9s99CIGeWBaHqgPdqRAADXNEVwVWR+nFHthZwIBjkwE dV+IfkuXjg2Kh9XuJ+63RHsj/NOp3SQqnLHoHW8WwEBEr9SNC48QFwm0cc4+vtlUCn bpmISLOR0IN9fKd5SFcUZLkCv9Dvu6+H/4oKtmYJAGEEw/6CYBW6BNrDhndGxuwmvz u8vUn0BG9nsFNRhBHcXcSdf6uh8gV1C4nn8IVnPLQRDv6qE0QHYQ7xSc2RmUABA+2L R4/CIvGBypI2g== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Kees Cook , Jim Cromie , Jean Delvare , Guenter Roeck , linux-hwmon@vger.kernel.org, "Gustavo A . R . Silva" , Sasha Levin Subject: [PATCH AUTOSEL 5.4 14/24] hwmon: (pc87360) Bounds check data->innr usage Date: Mon, 22 Jan 2024 10:16:28 -0500 Message-ID: <20240122151659.997085-14-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240122151659.997085-1-sashal@kernel.org> References: <20240122151659.997085-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 5.4.267 Content-Transfer-Encoding: 8bit From: Kees Cook [ Upstream commit 4265eb062a7303e537ab3792ade31f424c3c5189 ] Without visibility into the initializers for data->innr, GCC suspects using it as an index could walk off the end of the various 14-element arrays in data. Perform an explicit clamp to the array size. Silences the following warning with GCC 12+: ../drivers/hwmon/pc87360.c: In function 'pc87360_update_device': ../drivers/hwmon/pc87360.c:341:49: warning: writing 1 byte into a region of size 0 [-Wstringop-overflow=] 341 | data->in_max[i] = pc87360_read_value(data, | ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~ 342 | LD_IN, i, | ~~~~~~~~~ 343 | PC87365_REG_IN_MAX); | ~~~~~~~~~~~~~~~~~~~ ../drivers/hwmon/pc87360.c:209:12: note: at offset 255 into destination object 'in_max' of size 14 209 | u8 in_max[14]; /* Register value */ | ^~~~~~ Cc: Jim Cromie Cc: Jean Delvare Cc: Guenter Roeck Cc: linux-hwmon@vger.kernel.org Signed-off-by: Kees Cook Reviewed-by: Gustavo A. R. Silva Link: https://lore.kernel.org/r/20231130200207.work.679-kees@kernel.org [groeck: Added comment into code clarifying context] Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin --- drivers/hwmon/pc87360.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/hwmon/pc87360.c b/drivers/hwmon/pc87360.c index 94f4b8b4a2ba..0cf603c8c9f9 100644 --- a/drivers/hwmon/pc87360.c +++ b/drivers/hwmon/pc87360.c @@ -1605,7 +1605,11 @@ static struct pc87360_data *pc87360_update_device(struct device *dev) } /* Voltages */ - for (i = 0; i < data->innr; i++) { + /* + * The min() below does not have any practical meaning and is + * only needed to silence a warning observed with gcc 12+. + */ + for (i = 0; i < min(data->innr, ARRAY_SIZE(data->in)); i++) { data->in_status[i] = pc87360_read_value(data, LD_IN, i, PC87365_REG_IN_STATUS); /* Clear bits */ -- 2.43.0