In the Linux kernel, the following vulnerability has been resolved:
backlight: ledbl: Hold ledaccess lock when calling ledsysfsdisable()
Lockdep detects the following issue on led-backlight removal: [ 142.315935] ------------[ cut here ]------------ [ 142.315954] WARNING: CPU: 2 PID: 292 at drivers/leds/led-core.c:455 ledsysfsenable+0x54/0x80 ... [ 142.500725] Call trace: [ 142.503176] ledsysfsenable+0x54/0x80 (P) [ 142.507370] ledblremove+0x80/0xa8 [ledbl] [ 142.511742] platformremove+0x30/0x58 [ 142.515501] device_remove+0x54/0x90 ...
Indeed, ledsysfsenable() has to be called with the led_access lock held.
Hold the lock when calling ledsysfsdisable().