On Mon, 2022年08月15日 at 05:00 +0000, Tzung-Bi Shih wrote: > Alternatively, I would prefer to fix the double-free by setting > `i2c_peripherals` to NULL after [1]. Since 'cros_laptop->num_i2c_peripherals' is assigned with nonzero value (otherwise the code on 'err_out' is not executed), setting 'i2c_peripherals' to NULL after [1] will cause dereferencing of NULL pointer in chromeos_laptop_destroy() at [2]. [1]: https://elixir.bootlin.com/linux/v5.19/source/drivers/platform/chrome/chromeos_laptop.c#L787 [2]: https://elixir.bootlin.com/linux/v5.19/source/drivers/platform/chrome/chromeos_laptop.c#L860 > After a quick glance, I found an invalid memory access at [2] if > `i2c_peripherals` is NULL (see [3]). After applying the patch, there will be no invalid memory access at [2] if 'i2c_peripherals' is NULL, because in this situation 'cros_laptop->num_i2c_peripherals' is zero and there is no single iteration of the loop. > Or was the double-free issue > discovered by > some static analysis? Yes, it was discovered by SVACE static analysis tool.