In the Linux kernel, the following vulnerability has been resolved:
gpio: cdev: fix kernel stack leak to user-space in error path
If we fail to acquire the GPIO chip guard in gpio_desc_to_lineinfo(), we
return immediately before zeroing the info struct we’ll end up passing
to the user-space later in lineinfo_get_v1(). This may leak the kernel
stack contents. Make gpio_desc_to_lineinfo() return int so that the
-ENODEV returned on failure to acquire the guard can be propagated to
the callers.
While not strictly necessary: move the memset() before trying to acquire
the SRCU read lock too for good measure.
