@@ -832,7 +832,6 @@ static long gpio_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
void __user *ip = (void __user *)arg;
struct gpio_desc *desc;
__u32 offset;
- int hwgpio;
/* We fail any subsequent ioctl():s when the chip is gone */
if (!gc)
@@ -860,12 +859,11 @@ static long gpio_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
if (copy_from_user(&lineinfo, ip, sizeof(lineinfo)))
return -EFAULT;
+ /* this doubles as a range check on line_offset */
desc = gpiochip_get_desc(gc, lineinfo.line_offset);
if (IS_ERR(desc))
return PTR_ERR(desc);
- hwgpio = gpio_chip_hwgpio(desc);
-
gpio_desc_to_lineinfo(desc, &lineinfo);
if (copy_to_user(ip, &lineinfo, sizeof(lineinfo)))
@@ -881,19 +879,18 @@ static long gpio_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
if (copy_from_user(&lineinfo, ip, sizeof(lineinfo)))
return -EFAULT;
+ /* this doubles as a range check on line_offset */
desc = gpiochip_get_desc(gc, lineinfo.line_offset);
if (IS_ERR(desc))
return PTR_ERR(desc);
- hwgpio = gpio_chip_hwgpio(desc);
-
- if (test_and_set_bit(hwgpio, cdev->watched_lines))
+ if (test_and_set_bit(lineinfo.line_offset, cdev->watched_lines))
return -EBUSY;
gpio_desc_to_lineinfo(desc, &lineinfo);
if (copy_to_user(ip, &lineinfo, sizeof(lineinfo))) {
- clear_bit(hwgpio, cdev->watched_lines);
+ clear_bit(lineinfo.line_offset, cdev->watched_lines);
return -EFAULT;
}
@@ -902,13 +899,10 @@ static long gpio_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
if (copy_from_user(&offset, ip, sizeof(offset)))
return -EFAULT;
- desc = gpiochip_get_desc(gc, offset);
- if (IS_ERR(desc))
- return PTR_ERR(desc);
-
- hwgpio = gpio_chip_hwgpio(desc);
+ if (offset >= cdev->gdev->ngpio)
+ return -EINVAL;
- if (!test_and_clear_bit(hwgpio, cdev->watched_lines))
+ if (!test_and_clear_bit(offset, cdev->watched_lines))
return -EBUSY;
return 0;
Remove recalculation of offset from desc, where desc itself was calculated from offset. There is no benefit from the desc -> hwgpio conversion in this context. The only implicit benefit of the offset -> desc -> hwgpio is the range check in the offset -> desc, but where desc is required you still get that, and where desc isn't required it is simpler to perform the range check directly. Signed-off-by: Kent Gibson <warthog618@gmail.com> --- drivers/gpio/gpiolib-cdev.c | 20 +++++++------------- 1 file changed, 7 insertions(+), 13 deletions(-)