Vulnerabilidad en kernel de Linux (CVE-2022-49842)

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ASoC: núcleo: Se corrige el use-after-free en snd_soc_exit() KASAN informa un use-after-free: ERROR: KASAN: use-after-free en device_del+0xb5b/0xc60 Lectura de tamaño 8 en la dirección ffff888008655050 por la tarea rmmod/387 CPU: 2 PID: 387 Comm: rmmod Nombre del hardware: QEMU Standard PC (i440FX + PIIX, 1996) Rastreo de llamadas: dump_stack_lvl+0x79/0x9a print_report+0x17f/0x47b kasan_report+0xbb/0xf0 device_del+0xb5b/0xc60 platform_device_del.part.0+0x24/0x200 platform_device_unregister+0x2e/0x40 snd_soc_exit+0xa/0x22 [snd_soc_core] __do_sys_delete_module.constprop.0+0x34f/0x5b0 do_syscall_64+0x3a/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd ... It's bacause in snd_soc_init(), snd_soc_util_init() is possble to fail, but its ret is ignored, which makes soc_dummy_dev unregistered twice. snd_soc_init() snd_soc_util_init() platform_device_register_simple(soc_dummy_dev) platform_driver_register() # fail platform_device_unregister(soc_dummy_dev) platform_driver_register() # success ... snd_soc_exit() snd_soc_util_exit() # soc_dummy_dev will be unregistered for second time To fix it, handle error and stop snd_soc_init() when util_init() fail. Also clean debugfs when util_init() or driver_register() fail.