4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Bartosz Golaszewski <brgl@xxxxxxxx>
commit ad537b822577fcc143325786cd6ad50d7b9df31c upstream.
GPIOEVENT_REQUEST_BOTH_EDGES is not a single flag, but a binary OR of
GPIOEVENT_REQUEST_RISING_EDGE and GPIOEVENT_REQUEST_FALLING_EDGE.
The expression 'le->eflags & GPIOEVENT_REQUEST_BOTH_EDGES' we'll get
evaluated to true even if only one event type was requested.
Fix it by checking both RISING & FALLING flags explicitly.
Fixes: 61f922db7221 ("gpio: userspace ABI for reading GPIO line events")
Signed-off-by: Bartosz Golaszewski <brgl@xxxxxxxx>
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpio/gpiolib.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -707,7 +707,8 @@ static irqreturn_t lineevent_irq_thread(
ge.timestamp = ktime_get_real_ns();
- if (le->eflags & GPIOEVENT_REQUEST_BOTH_EDGES) {
+ if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE
+ && le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) {
int level = gpiod_get_value_cansleep(le->desc);
if (level)