linux-kernel - [PATCH 5.2 24/85] gpio: fix line flag validation in linehandle

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20190918061234.924147200@linuxfoundation.org>
Date:   Wed, 18 Sep 2019 08:18:42 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Kent Gibson <warthog618@...il.com>,
        Bartosz Golaszewski <bgolaszewski@...libre.com>
Subject: [PATCH 5.2 24/85] gpio: fix line flag validation in linehandle_create

From: Kent Gibson <warthog618@...il.com>

commit e95fbc130a162ba9ad956311b95aa0da269eea48 upstream.

linehandle_create should not allow both GPIOHANDLE_REQUEST_INPUT
and GPIOHANDLE_REQUEST_OUTPUT to be set.

Fixes: d7c51b47ac11 ("gpio: userspace ABI for reading/writing GPIO lines")
Cc: stable <stable@...r.kernel.org>
Signed-off-by: Kent Gibson <warthog618@...il.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@...libre.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 drivers/gpio/gpiolib.c |    8 ++++++++
 1 file changed, 8 insertions(+)

--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -536,6 +536,14 @@ static int linehandle_create(struct gpio
 		return -EINVAL;
 
 	/*
+	 * Do not allow both INPUT & OUTPUT flags to be set as they are
+	 * contradictory.
+	 */
+	if ((lflags & GPIOHANDLE_REQUEST_INPUT) &&
+	    (lflags & GPIOHANDLE_REQUEST_OUTPUT))
+		return -EINVAL;
+
+	/*
 	 * Do not allow OPEN_SOURCE & OPEN_DRAIN flags in a single request. If
 	 * the hardware actually supports enabling both at the same time the
 	 * electrical result would be disastrous.