| Message ID | 20240523085332.1801-1-hagarhem@amazon.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v4] gpio: prevent potential speculation leaks in gpio_device_get_desc() | expand |
From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> On Thu, 23 May 2024 08:53:32 +0000, Hagar Hemdan wrote: > Userspace may trigger a speculative read of an address outside the gpio > descriptor array. > Users can do that by calling gpio_ioctl() with an offset out of range. > Offset is copied from user and then used as an array index to get > the gpio descriptor without sanitization in gpio_device_get_desc(). > > This change ensures that the offset is sanitized by using > array_index_nospec() to mitigate any possibility of speculative > information leaks. > > [...] Applied, thanks! [1/1] gpio: prevent potential speculation leaks in gpio_device_get_desc() commit: d795848ecce24a75dfd46481aee066ae6fe39775 Best regards,
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index fa62367ee929..1a9aadd4c803 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -17,6 +17,7 @@ #include <linux/list.h> #include <linux/lockdep.h> #include <linux/module.h> +#include <linux/nospec.h> #include <linux/of.h> #include <linux/pinctrl/consumer.h> #include <linux/seq_file.h> @@ -198,7 +199,7 @@ gpio_device_get_desc(struct gpio_device *gdev, unsigned int hwnum) if (hwnum >= gdev->ngpio) return ERR_PTR(-EINVAL); - return &gdev->descs[hwnum]; + return &gdev->descs[array_index_nospec(hwnum, gdev->ngpio)]; } EXPORT_SYMBOL_GPL(gpio_device_get_desc);
Userspace may trigger a speculative read of an address outside the gpio descriptor array. Users can do that by calling gpio_ioctl() with an offset out of range. Offset is copied from user and then used as an array index to get the gpio descriptor without sanitization in gpio_device_get_desc(). This change ensures that the offset is sanitized by using array_index_nospec() to mitigate any possibility of speculative information leaks. This bug was discovered and resolved using Coverity Static Analysis Security Testing (SAST) by Synopsys, Inc. Signed-off-by: Hagar Hemdan <hagarhem@amazon.com> --- v4: removed Fixes commit. --- drivers/gpio/gpiolib.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)