Vulnerabilidad en kernel de Linux (CVE-2024-50150)

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: usb: typec: altmode debería mantener la referencia al padre La versión del dispositivo altmode hace referencia a su dispositivo padre, pero sin mantener una referencia a él. Al registrar el altmode, se obtiene una referencia al padre y se coloca en la función de lanzamiento. Antes de esta corrección, al usar CONFIG_DEBUG_KOBJECT_RELEASE, vemos problemas como este: [ 43.572860] kobject: 'port0.0' (ffff8880057ba008): kobject_release, parent 000000000000000 (delayed 3000) [ 43.573532] kobject: 'port0.1' (ffff8880057bd008): kobject_release, parent 000000000000000 (delayed 1000) [ 43.574407] kobject: 'port0' (ffff8880057b9008): kobject_release, parent 0000000000000000 (delayed 3000) [ 43.575059] kobject: 'port1.0' (ffff8880057ca008): kobject_release, padre 0000000000000000 (retrasado 4000) [ 43.575908] kobject: 'port1.1' (ffff8880057c9008): kobject_release, padre 0000000000000000 (retrasado 4000) [ 43.576908] kobject: 'typec' (ffff8880062dbc00): kobject_release, padre 000000000000000 (retrasado 4000) [ 43.577769] kobject: 'port1' (ffff8880057bf008): kobject_release, padre 0000000000000000 (retrasado 3000) [ 46.612867] ======================================================================= [ 46.613402] ERROR: KASAN: slab-use-after-free en typec_altmode_release+0x38/0x129 [ 46.614003] Lectura de tamaño 8 en la dirección ffff8880057b9118 por la tarea kworker/2:1/48 [ 46.614538] [ 46.614668] CPU: 2 UID: 0 PID: 48 Comm: kworker/2:1 No contaminado 6.12.0-rc1-00138-gedbae730ad31 #535 [ 46.615391] Nombre del hardware: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014 [ 46.616042] Cola de trabajo: eventos kobject_delayed_cleanup [ 46.616446] Seguimiento de llamadas: [ 46.616648] [ 46.616820] dump_stack_lvl+0x5b/0x7c [ 46.617112] ? kmem_cache_debug_flags+0xc/0x1d [ 46.618807] ? typec_altmode_release+0x38/0x129 [ 46.619161] kasan_report+0x8d/0xb4 [ 46.619447] ? proceso_trabajo_programado+0x3cb/0x85f [ 46.620185] tipoc_modo_alt_release+0x38/0x129 [ 46.620537] ? proceso_trabajo_programado+0x3cb/0x85f [ 46.620907] dispositivo_release+0xaf/0xf2 [ 46.621206] limpieza_retrasada_de_objetos+0x13b/0x17a [ 46.621584] proceso_trabajo_programado+0x4f6/0x85f [ 46.621955] ? __pfx_process_scheduled_works+0x10/0x10 [ 46.622353] ? hlock_class+0x31/0x9a [ 46.622647] ? lock_acquired+0x361/0x3c3 [ 46.622956] ? move_linked_works+0x46/0x7d [ 46.623277] subproceso de trabajo+0x1ce/0x291 [ 46.623582] ? __kthread_parkme+0xc8/0xdf [ 46.623900] ? __pfx_worker_thread+0x10/0x10 [ 46.624236] kthread+0x17e/0x190 [ 46.624501] ? kthread+0xfb/0x190 [ 46.624756] ? __pfx_kthread+0x10/0x10 [ 46.625015] ret_from_fork+0x20/0x40 [ 46.625268] ? __pfx_kthread+0x10/0x10 [ 46.625532] ret_from_fork_asm+0x1a/0x30 [ 46.625805] [ 46.625953] [ 46.626056] Asignado por la tarea 678: [ 46.626287] kasan_save_stack+0x24/0x44 [ 46.626555] kasan_save_track+0x14/0x2d [ 46.626811] __kasan_kmalloc+0x3f/0x4d [ 46.627049] __kmalloc_noprof+0x1bf/0x1f0 [ 46.627362] typec_register_port+0x23/0x491 [ 46.627698] cros_typec_probe+0x634/0xbb6 [ 46.628026] platform_probe+0x47/0x8c [ 46.628311] really_probe+0x20a/0x47d [ 46.628605] device_driver_attach+0x39/0x72 [ 46.628940] bind_store+0x87/0xd7 [ 46.629213] kernfs_fop_write_iter+0x1aa/0x218 [ 46.629574] vfs_write+0x1d6/0x29b [ 46.629856] ksys_write+0xcd/0x13b [ 46.630128] do_syscall_64+0xd4/0x139 [ 46.630420] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 46.630820] [ 46.630946] Liberado por la tarea 48: [ 46.631182] kasan_save_stack+0x24/0x44 [ 46.631493] kasan_save_track+0x14/0x2d [ 46.631799] kasan_save_free_info+0x3f/0x4d [ 46.632144] __kasan_slab_free+0x37/0x45 [ 46.632474] ---truncado---