CVE-2025-21948

In the Linux kernel, the following vulnerability has been resolved: HID: appleir: Fix potential NULL dereference at raw event handle Syzkaller reports a NULL pointer dereference issue in input_event(). BUG: KASAN: null-ptr-deref in instrument_atomic_read include/linux/instrumented.h:68 [inline] BUG: KASAN: null-ptr-deref in _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] BUG: KASAN: null-ptr-deref in is_event_supported drivers/input/input.c:67 [inline] BUG: KASAN: null-ptr-deref in input_event+0x42/0xa0 drivers/input/input.c:395 Read of size 8 at addr 0000000000000028 by task syz-executor199/2949 CPU: 0 UID: 0 PID: 2949 Comm: syz-executor199 Not tainted 6.13.0-rc4-syzkaller-00076-gf097a36ef88d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 kasan_report+0xd9/0x110 mm/kasan/report.c:602 check_region_inline mm/kasan/generic.c:183 [inline] kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189 instrument_atomic_read include/linux/instrumented.h:68 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] is_event_supported drivers/input/input.c:67 [inline] input_event+0x42/0xa0 drivers/input/input.c:395 input_report_key include/linux/input.h:439 [inline] key_down drivers/hid/hid-appleir.c:159 [inline] appleir_raw_event+0x3e5/0x5e0 drivers/hid/hid-appleir.c:232 __hid_input_report.constprop.0+0x312/0x440 drivers/hid/hid-core.c:2111 hid_ctrl+0x49f/0x550 drivers/hid/usbhid/hid-core.c:484 __usb_hcd_giveback_urb+0x389/0x6e0 drivers/usb/core/hcd.c:1650 usb_hcd_giveback_urb+0x396/0x450 drivers/usb/core/hcd.c:1734 dummy_timer+0x17f7/0x3960 drivers/usb/gadget/udc/dummy_hcd.c:1993 __run_hrtimer kernel/time/hrtimer.c:1739 [inline] __hrtimer_run_queues+0x20a/0xae0 kernel/time/hrtimer.c:1803 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1820 handle_softirqs+0x206/0x8d0 kernel/softirq.c:561 __do_softirq kernel/softirq.c:595 [inline] invoke_softirq kernel/softirq.c:435 [inline] __irq_exit_rcu+0xfa/0x160 kernel/softirq.c:662 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1049 </IRQ> <TASK> asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 __mod_timer+0x8f6/0xdc0 kernel/time/timer.c:1185 add_timer+0x62/0x90 kernel/time/timer.c:1295 schedule_timeout+0x11f/0x280 kernel/time/sleep_timeout.c:98 usbhid_wait_io+0x1c7/0x380 drivers/hid/usbhid/hid-core.c:645 usbhid_init_reports+0x19f/0x390 drivers/hid/usbhid/hid-core.c:784 hiddev_ioctl+0x1133/0x15b0 drivers/hid/usbhid/hiddev.c:794 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f </TASK> This happens due to the malformed report items sent by the emulated device which results in a report, that has no fields, being added to the report list. Due to this appleir_input_configured() is never called, hidinput_connect() fails which results in the HID_CLAIMED_INPUT flag is not being set. However, it does not make appleir_probe() fail and lets the event callback to be called without the associated input device. Thus, add a check for the HID_CLAIMED_INPUT flag and leave the event hook early if the driver didn't claim any input_dev for some reason. Moreover, some other hid drivers accessing input_dev in their event callbacks do have similar checks, too. Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Configurations

Configuration 1 (hide)

OR cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc5:*:*:*:*:*:*

History

11 Apr 2025, 13:11

Type Values Removed Values Added
First Time Linux linux Kernel
Linux
CWE CWE-476
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 5.5
CPE cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
References () https://git.kernel.org/stable/c/0df1ac8ee417ad76760ff076faa4518a4d861894 - () https://git.kernel.org/stable/c/0df1ac8ee417ad76760ff076faa4518a4d861894 - Patch
References () https://git.kernel.org/stable/c/2ff5baa9b5275e3acafdf7f2089f74cccb2f38d1 - () https://git.kernel.org/stable/c/2ff5baa9b5275e3acafdf7f2089f74cccb2f38d1 - Patch
References () https://git.kernel.org/stable/c/68cdf6710f228dfd74f66ec61fbe636da2646a73 - () https://git.kernel.org/stable/c/68cdf6710f228dfd74f66ec61fbe636da2646a73 - Patch
References () https://git.kernel.org/stable/c/6db423b00940b05df2a1265d3c7eabafe9f1734c - () https://git.kernel.org/stable/c/6db423b00940b05df2a1265d3c7eabafe9f1734c - Patch
References () https://git.kernel.org/stable/c/8d39eb8c5e14f2f0f441eed832ef8a7b654e6fee - () https://git.kernel.org/stable/c/8d39eb8c5e14f2f0f441eed832ef8a7b654e6fee - Patch
References () https://git.kernel.org/stable/c/b1d95d733cd6e74f595653daddcfc357bea461e8 - () https://git.kernel.org/stable/c/b1d95d733cd6e74f595653daddcfc357bea461e8 - Patch
References () https://git.kernel.org/stable/c/d335fce8b88b2353f4bb20c631698e20384e3610 - () https://git.kernel.org/stable/c/d335fce8b88b2353f4bb20c631698e20384e3610 - Patch
References () https://git.kernel.org/stable/c/fc69e2c3219d433caabba4b5d6371ba726a4b37f - () https://git.kernel.org/stable/c/fc69e2c3219d433caabba4b5d6371ba726a4b37f - Patch
Summary
  • (es) En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: HID: appleir: Se corrige una posible desreferencia de puntero NULL en el identificador de evento sin procesar Syzkaller informa un problema de desreferencia de puntero NULL en input_event(). ERROR: KASAN: null-ptr-deref en instrument_atomic_read include/linux/instrumented.h:68 [en línea] ERROR: KASAN: null-ptr-deref en _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [en línea] ERROR: KASAN: null-ptr-deref en is_event_supported drivers/input/input.c:67 [en línea] ERROR: KASAN: null-ptr-deref en input_event+0x42/0xa0 drivers/input/input.c:395 Lectura de tamaño 8 en la dirección 0000000000000028 por la tarea syz-executor199/2949 CPU: 0 UID: 0 PID: 2949 Comm: syz-executor199 No contaminado 6.13.0-rc4-syzkaller-00076-gf097a36ef88d #0 Nombre del hardware: Google Google Compute Engine/Google Compute Engine, BIOS Google 13/09/2024 Rastreo de llamadas: __dump_stack lib/dump_stack.c:94 [en línea] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 kasan_report+0xd9/0x110 mm/kasan/report.c:602 check_region_inline mm/kasan/generic.c:183 [en línea] kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189 instrument_atomic_read include/linux/instrumented.h:68 [en línea] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [en línea] es_evento_compatible drivers/input/input.c:67 [en línea] evento_entrada+0x42/0xa0 drivers/input/input.c:395 clave_informe_entrada include/linux/input.h:439 [en línea] tecla_abajo drivers/hid/hid-appleir.c:159 [en línea] evento_sin_usar_appleir+0x3e5/0x5e0 drivers/hid/hid-appleir.c:232 __hid_input_report.constprop.0+0x312/0x440 drivers/hid/hid-core.c:2111 hid_ctrl+0x49f/0x550 drivers/hid/usbhid/hid-core.c:484 __usb_hcd_giveback_urb+0x389/0x6e0 controladores/usb/core/hcd.c:1650 usb_hcd_giveback_urb+0x396/0x450 controladores/usb/core/hcd.c:1734 temporizador ficticio+0x17f7/0x3960 controladores/usb/gadget/udc/dummy_hcd.c:1993 __run_hrtimer kernel/time/hrtimer.c:1739 [en línea] __hrtimer_run_queues+0x20a/0xae0 kernel/time/hrtimer.c:1803 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1820 handle_softirqs+0x206/0x8d0 kernel/softirq.c:561 __do_softirq kernel/softirq.c:595 [en línea] invocar_softirq kernel/softirq.c:435 [en línea] __irq_exit_rcu+0xfa/0x160 kernel/softirq.c:662 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [en línea] sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 __mod_timer+0x8f6/0xdc0 kernel/time/timer.c:1185 add_timer+0x62/0x90 kernel/time/timer.c:1295 schedule_timeout+0x11f/0x280 kernel/time/sleep_timeout.c:98 usbhid_wait_io+0x1c7/0x380 drivers/hid/usbhid/hid-core.c:645 usbhid_init_reports+0x19f/0x390 drivers/hid/usbhid/hid-core.c:784 hiddev_ioctl+0x1133/0x15b0 drivers/hid/usbhid/hiddev.c:794 vfs_ioctl fs/ioctl.c:51 [en línea] Esto sucede debido a los elementos de informe mal formados enviados por el dispositivo emulado, lo que da como resultado que se agregue a la lista de informes un informe que no tiene campos. Debido a que appleir_input_configured() nunca se llama, hidinput_connect() falla, lo que provoca que no se configure el indicador HID_CLAIMED_INPUT. Sin embargo, esto no provoca el fallo de appleir_probe() y permite que la devolución de llamada del evento se llame sin el dispositivo de entrada asociado. Por lo tanto, se debe añadir una comprobación para el indicador HID_CLAIMED_INPUT y abandonar el gancho de evento antes de tiempo si el controlador no solicitó ningún input_dev por alguna razón. Además, otros controladores HID que acceden a input_dev en sus devoluciones de llamada de evento también tienen comprobaciones similares. Encontrado por el Centro de Verificación de Linux (linuxtesting.org) con Syzkaller.

01 Apr 2025, 16:15

Type Values Removed Values Added
New CVE

Information

Published : 2025-04-01 16:15

Updated : 2025-04-11 13:11


NVD link : CVE-2025-21948

Mitre link : CVE-2025-21948

CVE.ORG link : CVE-2025-21948


JSON object : View

Products Affected

linux

  • linux_kernel
CWE
CWE-476

NULL Pointer Dereference