CVE-2022-49939

In the Linux kernel, the following vulnerability has been resolved: binder: fix UAF of ref->proc caused by race condition A transaction of type BINDER_TYPE_WEAK_HANDLE can fail to increment the reference for a node. In this case, the target proc normally releases the failed reference upon close as expected. However, if the target is dying in parallel the call will race with binder_deferred_release(), so the target could have released all of its references by now leaving the cleanup of the new failed reference unhandled. The transaction then ends and the target proc gets released making the ref->proc now a dangling pointer. Later on, ref->node is closed and we attempt to take spin_lock(&ref->proc->inner_lock), which leads to the use-after-free bug reported below. Let's fix this by cleaning up the failed reference on the spot instead of relying on the target to do so. ================================================================== BUG: KASAN: use-after-free in _raw_spin_lock+0xa8/0x150 Write of size 4 at addr ffff5ca207094238 by task kworker/1:0/590 CPU: 1 PID: 590 Comm: kworker/1:0 Not tainted 5.19.0-rc8 #10 Hardware name: linux,dummy-virt (DT) Workqueue: events binder_deferred_func Call trace: dump_backtrace.part.0+0x1d0/0x1e0 show_stack+0x18/0x70 dump_stack_lvl+0x68/0x84 print_report+0x2e4/0x61c kasan_report+0xa4/0x110 kasan_check_range+0xfc/0x1a4 __kasan_check_write+0x3c/0x50 _raw_spin_lock+0xa8/0x150 binder_deferred_func+0x5e0/0x9b0 process_one_work+0x38c/0x5f0 worker_thread+0x9c/0x694 kthread+0x188/0x190 ret_from_fork+0x10/0x20
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:6.0:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.0:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.0:rc3:*:*:*:*:*:*

History

14 Nov 2025, 19:39

Type Values Removed Values Added
Summary
  • (es) En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: binder: arreglo UAF de ref->proc causado por condición de ejecución Una transacción de tipo BINDER_TYPE_WEAK_HANDLE puede fallar al incrementar la referencia para un nodo. En este caso, el proc objetivo normalmente libera la referencia fallida al cerrar como se espera. Sin embargo, si el objetivo está muriendo en paralelo la llamada competirá con binder_deferred_release(), por lo que el objetivo podría haber liberado todas sus referencias por ahora dejando la limpieza de la nueva referencia fallida sin manejar. La transacción entonces termina y el proc objetivo se libera haciendo que ref->proc ahora sea un puntero colgante. Más tarde, ref->node se cierra e intentamos tomar spin_lock(&ref->proc->inner_lock), lo que lleva al error de Use-After-Free reportado a continuación. Vamos a arreglar esto limpiando la referencia fallida en el acto en lugar de depender de que el objetivo lo haga. ====================================================================== ERROR: KASAN: Use-After-Free en _raw_spin_lock+0xa8/0x150 Escritura de tamaño 4 en la dirección ffff5ca207094238 por la tarea kworker/1:0/590 CPU: 1 PID: 590 Comm: kworker/1:0 No contaminado 5.19.0-rc8 #10 Nombre del hardware: linux,dummy-virt (DT) Cola de trabajo: eventos binder_deferred_func Rastreo de llamadas: dump_backtrace.part.0+0x1d0/0x1e0 show_stack+0x18/0x70 dump_stack_lvl+0x68/0x84 print_report+0x2e4/0x61c kasan_report+0xa4/0x110 kasan_check_range+0xfc/0x1a4 __kasan_check_write+0x3c/0x50 _raw_spin_lock+0xa8/0x150 binder_deferred_func+0x5e0/0x9b0 process_one_work+0x38c/0x5f0 worker_thread+0x9c/0x694 kthread+0x188/0x190 ret_from_fork+0x10/0x20
CPE cpe:2.3:o:linux:linux_kernel:6.0:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.0:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.0:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
CWE CWE-416
CWE-362
References () https://git.kernel.org/stable/c/06e5b43ca4dab06a92bf4c2f33766e6fb11b880a - () https://git.kernel.org/stable/c/06e5b43ca4dab06a92bf4c2f33766e6fb11b880a - Patch
References () https://git.kernel.org/stable/c/229f47603dd306bc0eb1a831439adb8e48bb0eae - () https://git.kernel.org/stable/c/229f47603dd306bc0eb1a831439adb8e48bb0eae - Patch
References () https://git.kernel.org/stable/c/30d0901b307f27d36b2655fb3048cf31ee0e89c0 - () https://git.kernel.org/stable/c/30d0901b307f27d36b2655fb3048cf31ee0e89c0 - Patch
References () https://git.kernel.org/stable/c/603a47f2ae56bf68288784d3c0a8c5b8e0a827ed - () https://git.kernel.org/stable/c/603a47f2ae56bf68288784d3c0a8c5b8e0a827ed - Patch
References () https://git.kernel.org/stable/c/9629f2dfdb1dad294b468038ff8e161e94d0b609 - () https://git.kernel.org/stable/c/9629f2dfdb1dad294b468038ff8e161e94d0b609 - Patch
References () https://git.kernel.org/stable/c/a0e44c64b6061dda7e00b7c458e4523e2331b739 - () https://git.kernel.org/stable/c/a0e44c64b6061dda7e00b7c458e4523e2331b739 - Patch
References () https://git.kernel.org/stable/c/c2a4b5dc8fa71af73bab704d0cac42ac39767ed6 - () https://git.kernel.org/stable/c/c2a4b5dc8fa71af73bab704d0cac42ac39767ed6 - Patch
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 7.0
First Time Linux
Linux linux Kernel

18 Jun 2025, 11:15

Type Values Removed Values Added
New CVE

Information

Published : 2025-06-18 11:15

Updated : 2025-11-14 19:39


NVD link : CVE-2022-49939

Mitre link : CVE-2022-49939

CVE.ORG link : CVE-2022-49939


JSON object : View

Products Affected

linux

  • linux_kernel
CWE
CWE-362

Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

CWE-416

Use After Free