Vulnerabilidad en kernel de Linux (CVE-2021-47284)

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: isdn: mISDN: netjet: Soluciona fallo en nj_probe: 'nj_setup' en netjet.c puede fallar con -EIO y en este caso 'card->irq' está inicializado y es más grande que cero. Una llamada posterior a 'nj_release' liberará el irq que no ha sido solicitado. Corrija este error eliminando la asignación anterior a 'card->irq' y simplemente mantenga la asignación antes de 'request_irq'. El registro de KASAN lo revela: [3.354615] ADVERTENCIA: CPU: 0 PID: 1 en kernel/irq/manage.c:1826 free_irq+0x100/0x480 [3.355112] Módulos vinculados en: [3.355310] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.13.0-rc1-00144-g25a1298726e #13 [ 3.355816 ] Nombre del hardware: PC estándar QEMU (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04 /01/2014 [ 3.356552 ] RIP: 0010:free_irq+0x100/0x480 [ 3.356820 ] Código: 6e 08 74 6f 4d 89 f4 e8 5e ac 09 00 4d 8b 74 24 18 4d 85 f6 75 e3 e8 f ac 09 00 8b 75 c8 48 c7 c7 78 c1 2e 85 e8 e0 cf f5 ff <0f> 0b 48 8b 75 c0 4c 89 ff e8 72 33 0b 03 48 8b 43 40 4c 8b a0 80 [ 3.358012 ] RSP: 17b48 EFLAGS: 00010082 [ 3.358357 ] RAX: 0000000000000000 RBX: ffff888104dc8000 RCX: 0000000000000000 [ 3.358814 ] RDX: ffff8881003c8000 RSI: ffffffff8124a9e6 RDI: 00000000ffffff ff [ 3.359272 ] RBP: ffffc90000017b88 R08: 0000000000000000 R09: 0000000000000000 [ 3.359732 ] R10: ffffc900000179f0 R11: 0000000000001d0 4 R12: 0000000000000000 [ 3.360195 ] R13 : ffff888107dc6000 R14: ffff888107dc6928 R15: ffff888104dc80a8 [ 3.360652 ] FS: 0000000000000000(0000) GS:ffff88817bc00000(0000) 00000000000 [ 3.361170 ] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3.361538 ] CR2: 00000000000000000 CR3: 000000000582e000 CR4: 00000000000006f0 [ 3.362003 ] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 3.362175 ] DR3: 000000000000000 0 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 3.362175 ] Seguimiento de llamadas: [ 3.362175 ] nj_release+0x51/0x1e0 [ 3.362175 ] nj_probe+0x450/0x950 [ 3,362175 ] ? pci_device_remove+0x110/0x110 [ 3.362175 ] local_pci_probe+0x45/0xa0 [ 3.362175 ] pci_device_probe+0x12b/0x1d0 [ 3.362175 ] really_probe+0x2a9/0x610 [ 3.362175 ]driver_probe_device+0x90/0x1d0 [3.362175]? mutex_lock_nested+0x1b/0x20 [3.362175] device_driver_attach+0x68/0x70 [3.362175] __driver_attach+0x124/0x1b0 [3.362175]? device_driver_attach+0x70/0x70 [3.362175] bus_for_each_dev+0xbb/0x110 [3.362175]? rdinit_setup+0x45/0x45 [ 3.362175 ] driver_attach+0x27/0x30 [ 3.362175 ] bus_add_driver+0x1eb/0x2a0 [ 3.362175 ] driver_register+0xa9/0x180 [ 3.362175 ] x82/0x90 [3.362175]? w6692_init+0x38/0x38 [3.362175] nj_init+0x36/0x38 [3.362175] do_one_initcall+0x7f/0x3d0 [3.362175]? rdinit_setup+0x45/0x45 [3.362175]? rcu_read_lock_sched_held+0x4f/0x80 [3.362175] kernel_init_freeable+0x2aa/0x301 [3.362175]? rest_init+0x2c0/0x2c0 [3.362175] kernel_init+0x18/0x190 [3.362175]? rest_init+0x2c0/0x2c0 [3.362175]? rest_init+0x2c0/0x2c0 [3.362175] ret_from_fork+0x1f/0x30 [3.362175] Pánico del kernel - no sincronizado: panic_on_warn establecido... [3.362175] CPU: 0 PID: 1 Comm: swapper/0 No contaminado 5.13.0-rc1-00144 -g25a1298726e #13 [ 3.362175 ] Nombre del hardware: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 01/04/2014 [ 3.362175 ] Seguimiento de llamadas: [ 3.362175 ] dump_stack+0xba/0xf5 [3.362175]? free_irq+0x100/0x480 [3.362175] pánico+0x15a/0x3f2 [3.362175]? __advertir+0xf2/0x150 [3.362175]? free_irq+0x100/0x480 [3.362175] __warn+0x108/0x150 [3.362175]? free_irq+0x100/0x480 [ 3.362175 ] report_bug+0x119/0x1c0 [ 3.362175 ] handle_bug+0x3b/0x80 [ 3.362175 ] exc_invalid_op+0x18/0x70 [ 3.362175 ] x12/0x20 [3.362175] RIP: 0010:free_irq+0x100 --- truncado---