diff mbox

gpiolib: shifters used as flags in gpio_ioctl()

Message ID 20160223094450.GB4030@mwanda
State New
Headers show

Commit Message

Dan Carpenter Feb. 23, 2016, 9:44 a.m. UTC 
We weren't testing whether the bits were set correctly because we used
shifters as flags.  It means that we give the user incorrect line
information in this new ioctl.

Fixes: 521a2ad6f862 ('gpio: add userspace ABI for GPIO line information')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

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Comments

Linus Walleij Feb. 23, 2016, 12:58 p.m. UTC | #1 
On Tue, Feb 23, 2016 at 10:44 AM, Dan Carpenter
<dan.carpenter@oracle.com> wrote:

> We weren't testing whether the bits were set correctly because we used
> shifters as flags.  It means that we give the user incorrect line
> information in this new ioctl.
>
> Fixes: 521a2ad6f862 ('gpio: add userspace ABI for GPIO line information')
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

Already wrote and queued a similar patch yesterday, but thanks anyway Dan!

Yours,
Linus Walleij
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diff mbox

Patch

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index b816469..d609e03 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -380,17 +380,19 @@  static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 		 * this GPIO so it can't use it.
 		 */
 		lineinfo.flags = 0;
-		if (desc->flags & (FLAG_REQUESTED | FLAG_IS_HOGGED |
-				   FLAG_USED_AS_IRQ | FLAG_EXPORT |
-				   FLAG_SYSFS))
+		if (desc->flags & ((1 << FLAG_REQUESTED) |
+				   (1 << FLAG_IS_HOGGED) |
+				   (1 << FLAG_USED_AS_IRQ) |
+				   (1 << FLAG_EXPORT) |
+				   (1 << FLAG_SYSFS)))
 			lineinfo.flags |= GPIOLINE_FLAG_KERNEL;
-		if (desc->flags & FLAG_IS_OUT)
+		if (test_bit(FLAG_IS_OUT, &desc->flags))
 			lineinfo.flags |= GPIOLINE_FLAG_IS_OUT;
-		if (desc->flags & FLAG_ACTIVE_LOW)
+		if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
 			lineinfo.flags |= GPIOLINE_FLAG_ACTIVE_LOW;
-		if (desc->flags & FLAG_OPEN_DRAIN)
+		if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
 			lineinfo.flags |= GPIOLINE_FLAG_OPEN_DRAIN;
-		if (desc->flags & FLAG_OPEN_SOURCE)
+		if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
 			lineinfo.flags |= GPIOLINE_FLAG_OPEN_SOURCE;
 
 		if (copy_to_user(ip, &lineinfo, sizeof(lineinfo)))