iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

gpio: GPIO_GET_CHIPINFO_IOCTL: Fix information leak

Browse Source 
The GPIO_GET_CHIPINFO_IOCTL handler allocates a gpiochip_info struct on the
stack and then passes it to copy_to_user(). But depending on the length of
the GPIO chip name and label the struct is only partially initialized.

This exposes the previous, potentially sensitive, stack content to the
issuing userspace application. To avoid this make sure that the struct is
fully initialized.

Cc: stable@vger.kernel.org
Fixes: 521a2ad6f862 ("gpio: add userspace ABI for GPIO line information")
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This commit is contained in:
Lars-Peter Clausen 2016-10-18 16:54:00 +02:00 committed by Linus Walleij
parent 1f1cc4566b
commit 0f4bbb2337
1 changed files with 2 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/gpio/gpiolib.c
View File

@ -823,6 +823,8 @@ static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
if (cmd == GPIO_GET_CHIPINFO_IOCTL) {
struct gpiochip_info chipinfo;
memset(&chipinfo, 0, sizeof(chipinfo));
strncpy(chipinfo.name, dev_name(&gdev->dev),
sizeof(chipinfo.name));
chipinfo.name[sizeof(chipinfo.name)-1] = '\0';