From nobody Mon Sep 28 02:58:33 2026 Received: from smtpbgau2.qq.com (smtpbgau2.qq.com [54.206.34.216]) (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 099831ABEDE; Thu, 27 Aug 2026 01:55:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=54.206.34.216 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787795723; cv=none; b=oLaYpQ5Ng9Pa7/vj6j7KSk7RybXkOGdccuW9Djo9F+d88d85ppJ/qxfEntSWxvn2JmLN76eBDU74UQfq2saAo1nljTP/u4Xpnyx7Yv2qOj/57Kaq8vKGXaUVnHFJfhRQr15f72VkEFA09RhFmJrzW6efFIT6sIxFjqKkgqUgvnU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787795723; c=relaxed/simple; bh=+vSiDmfesHteRofWu9YnnJphCrUSSUwaHMRRfgYOmTE=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=QOjTo7jWS7Ap8M7BopAgi8ebROijMKmEQwucZqeqdZ+CMpwgsosmr+b9cyaQ/ATXNLhiQTPBVQ+2f2zA4I2FrXRYMrcSbCwaQbWEsn2CuPqaFs2CQZpcGrIlx9uw+ywZqiZNjq1Uh+3kueWaMaSC90nAkwzqDXwxsMJVAyaxvfo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinsec.com.cn; spf=pass smtp.mailfrom=kylinsec.com.cn; arc=none smtp.client-ip=54.206.34.216 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinsec.com.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kylinsec.com.cn X-QQ-mid: zesmtpgz4t1787795693t5ca7b669 X-QQ-Originating-IP: oycE74GwGx4odGFUwygfHSfIm2zwZaPcCTkmglsnPSs= Received: from localhost.localdomain ( [111.8.45.130]) by bizesmtp.qq.com (ESMTP) with id ; Thu, 27 Aug 2026 09:54:48 +0800 (CST) X-QQ-SSF: 0000000000000000000000000000000 X-QQ-GoodBg: 0 X-BIZMAIL-ID: 4192742800306822609 EX-QQ-RecipientCnt: 7 From: Liu Dalin To: Alexandre Belloni Cc: linux-rtc@vger.kernel.org, linux-kernel@vger.kernel.org, Liu Dalin , Deng Yingchao , Qin Yungao , Luo Qiu Subject: [PATCH] rtc: dev: zero-initialize struct rtc_wkalrm to prevent information leak Date: Thu, 27 Aug 2026 09:54:44 +0800 Message-ID: X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-QQ-SENDSIZE: 520 Feedback-ID: zesmtpgz:kylinsec.com.cn:qybglogicsvrgz:qybglogicsvrgz6b-0 X-QQ-XMAILINFO: MDGUoPnBmw7sh4jokFVIlVI5f0X6NI/omEJGwdQWURBo6uLB+0pVJtI0 t+Jmyy6h2XOXsP5XrrbFGC59Cylb9vCjliVAqqn1dOAlIvlRDKBFqtKu3qhLMtLYUz/hN76 kheBlpQvpPdYexsHSJ8c4ihO0xqROGpGeu/MI0JEnmCfxKvmWmrwvGzBawro+xh1LTyJjJY lVDpycu4iniAiF046Mt1NKWMAjiyPqUgNPzseSuMuREki4gYp/6pxxRWnzGwlruorjN9Kzo RgQV8Kd7ZZKcWJRex2g4RhydQ9c1IKFCA9N0FKQG9vQ2sfCU/jZ5RwGdbP2j/tEvrGnfONP vYzCFWUjKSV6i/GjYyTwDbU/naItGob/+MJgNjzpDjwlDus527Ckexh4NAV0y7UFFjZSZYq EJc87NztSyVfuwGqRx/pRVwH103j2l08WM5dHmNfhO02nkmyC/gWwdddjegUIaREcwnDP91 q48KYF07+hevrar0udPsFKjg8tmp1jzPzQGdOHYZXFuDXuQt92U6hvmWzxnZBA0AiwrfDb4 R8W0hR27KzzccYqotpQ/SM3D70IWRkR5YlrfOWyFlf8Z8qjRYt0PvsYNYTrc/iKHIjRd2Zu 6yrChjfUO7HAld7AB/7r7bmr/+yOk1kUqE3DZt5Ed3cZtvMHjNTNQqE9BNvjcslFv7FmNPQ e/iFRvjJfTu9W/8JUCQuTHVaqz/7pYyMy+I05fQto2JkTdihKUe2YcMhvzxf/1yESPeJjCp YdqhU2lXSdZWcbUQT+bnJk9NpHMTerd0JPl8vJO0xBaFgFH46tXz55liieCbIvvIX/ECgw/ Ct7BvfHhOTI9cXSFWbTH9Zj7j/5gHeIKmr/KbT+cE3Py3gdr2pIaNrRRus8IiZdcvQvkrno OnIkBD1vF/bPDow8bel1Wy37lEN+WVJWGs8VSb/K5Ls6Tr9ZdEuuuxGWWrpTikWthexjGi8 CjCsyOs5Up9Rvp1cROehcLbImejg8iTErazYGTECLWp1VDZlM0ZtN2WKd/K/YtttIJkk69U Mop8FMJ+AJ2fDc+RYzXgjFN6Wt4GBxsOY3NbVrPA== X-QQ-XMRINFO: NS+P29fieYNwqS3WCnRCOn9D1NpZuCnCRA== X-QQ-RECHKSPAM: 0 Content-Type: text/plain; charset="utf-8" The struct rtc_wkalrm has padding holes after the 'pending' member. When returned to userspace via the RTC_WKALRM_RD ioctl, uninitialized kernel stack data residing in these holes may be leaked. Zero-initialize the struct at declaration to eliminate this information leak risk. Fixes smatch warnings: - drivers/rtc/dev.c:392 rtc_dev_ioctl() warn: check that 'alarm' doesn't leak information (struct has a hole after 'pending') Fixes: 36e14f5fdfdf ("rtc: rename core files") Assisted-by: smatch:2.0 [static analysis] Signed-off-by: Liu Dalin --- drivers/rtc/dev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/rtc/dev.c b/drivers/rtc/dev.c index 8ba7c25d2565..be173c9511fa 100644 --- a/drivers/rtc/dev.c +++ b/drivers/rtc/dev.c @@ -216,7 +216,7 @@ static long rtc_dev_ioctl(struct file *file, struct rtc_device *rtc =3D file->private_data; const struct rtc_class_ops *ops =3D rtc->ops; struct rtc_time tm; - struct rtc_wkalrm alarm; + struct rtc_wkalrm alarm =3D { 0 }; struct rtc_param param; void __user *uarg =3D (void __user *)arg; =20 --=20 2.43.0