lkml.org 
[lkml]   [2018]   [Feb]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 4.9 06/86] gpio: Fix kernel stack leak to userspace
Date
4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Linus Walleij <linus.walleij@linaro.org>

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 <arnd@arndb.de>
Reviewed-by: Bartosz Golaszewski <brgl@bgdev.pl>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/gpio/gpiolib.c | 3 +++
1 file changed, 3 insertions(+)

--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -705,6 +705,9 @@ 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);


\
 
 \ /
  Last update: 2018-02-02 18:06    [W:0.509 / U:0.520 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site