From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AH8x227u87OgZU0QiVdhoL3r3hz1jUWVhWXeQNnmQuiUO96SUpgaceMmGDCeaAXAtIE7t2nkmLvv ARC-Seal: i=1; a=rsa-sha256; t=1517591713; cv=none; d=google.com; s=arc-20160816; b=bWVU0kWCfcQLJe+9Oi3WEObYiwHt94cauRZtyk/7T+52Of8MWf7mHiPCmlt/RaYb1G 8QfhbixpKxiO9LZFZTDZXyLsHlQqIt53eUptAmn1dIW8CPsV/TQUbqD9X+v7bP99xoC+ WBRqF2a/8MoUJ3zQ27gzyK4pbVLIjV49qDUOYZrgT2bQco5NLsHHLBwyETYWDMbxmZJk e/tBqv2skYaOd3Whg5nIeLi2jI6WweOJ1h5Jp5b5HgnzciFeP/uPx4zGyXuykJzw6Lvu /Bga+xWlrihIOfaHs2sHhr114cWLLyy0ctDxcfj0UODGFwIachX+VXUSeKYGfX9irRGG CTKw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=McUAG05b4hKbKkaFeN8P85amwNZagFL9MDOGFbhNfl0=; b=ebr1ay1anVNkgEseKJjVMBIhM9hHFKFbLrhQdvPbGPfgjmYJRN42zJy/3IuJfSVW4e 7fbDNY0TQl2fllGDo1oWtg6ZXhef0yTZ5nf6H4k10irS/ZCV5HbKnw4coB7wcjbC9V46 SpxBf9LhM4rzw3o8qoPcewuAWBevilp5lDYEHKbJtp1Ke+LXZu3cKP94Dbfvjavq/pr4 yahIrOizhjFG/AkY5mvTqu6AQO7R55ndS44zBI/N3TaTyi2u9/54/nFb5ETW9sK4CIgT AnuTWGzNNHkYa2+fTCWlK40Y+xNeqtnR98E8ZR/bASjCb/7ChBSQm/LsZt69Dps+bHme z5vQ== ARC-Authentication-Results: i=1; mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.71.90 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org Authentication-Results: mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.71.90 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Arnd Bergmann , Bartosz Golaszewski , Linus Walleij Subject: [PATCH 4.15 04/55] gpio: Fix kernel stack leak to userspace Date: Fri, 2 Feb 2018 17:58:22 +0100 Message-Id: <20180202140826.450879851@linuxfoundation.org> X-Mailer: git-send-email 2.16.1 In-Reply-To: <20180202140826.117602411@linuxfoundation.org> References: <20180202140826.117602411@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1591309489818363187?= X-GMAIL-MSGID: =?utf-8?q?1591310248037182945?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Linus Walleij commit 24bd3efc9d1efb5f756a7c6f807a36ddb6adc671 upstream. The GPIO event descriptor was leaking kernel stack to userspace because we don't zero the variable before use. Ooops. Fix this. Reported-by: Arnd Bergmann Reviewed-by: Bartosz Golaszewski Reviewed-by: Arnd Bergmann Signed-off-by: Linus Walleij Signed-off-by: Greg Kroah-Hartman --- drivers/gpio/gpiolib.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -732,6 +732,9 @@ static irqreturn_t lineevent_irq_thread( struct gpioevent_data ge; int ret, level; + /* Do not leak kernel stack to userspace */ + memset(&ge, 0, sizeof(ge)); + ge.timestamp = ktime_get_real_ns(); level = gpiod_get_value_cansleep(le->desc);