CVE-2024-56670

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: u_serial: Fix the issue that gs_start_io crashed due to accessing null pointer Considering that in some extreme cases, when u_serial driver is accessed by multiple threads, Thread A is executing the open operation and calling the gs_open, Thread B is executing the disconnect operation and calling the gserial_disconnect function,The port->port_usb pointer will be set to NULL. E.g. Thread A Thread B gs_open() gadget_unbind_driver() gs_start_io() composite_disconnect() gs_start_rx() gserial_disconnect() ... ... spin_unlock(&port->port_lock) status = usb_ep_queue() spin_lock(&port->port_lock) spin_lock(&port->port_lock) port->port_usb = NULL gs_free_requests(port->port_usb->in) spin_unlock(&port->port_lock) Crash This causes thread A to access a null pointer (port->port_usb is null) when calling the gs_free_requests function, causing a crash. If port_usb is NULL, the release request will be skipped as it will be done by gserial_disconnect. So add a null pointer check to gs_start_io before attempting to access the value of the pointer port->port_usb. Call trace: gs_start_io+0x164/0x25c gs_open+0x108/0x13c tty_open+0x314/0x638 chrdev_open+0x1b8/0x258 do_dentry_open+0x2c4/0x700 vfs_open+0x2c/0x3c path_openat+0xa64/0xc60 do_filp_open+0xb8/0x164 do_sys_openat2+0x84/0xf0 __arm64_sys_openat+0x70/0x9c invoke_syscall+0x58/0x114 el0_svc_common+0x80/0xe0 do_el0_svc+0x1c/0x28 el0_svc+0x38/0x68
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:6.13:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.13:rc2:*:*:*:*:*:*

History

06 Jan 2025, 18:13

Type Values Removed Values Added
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 5.5
CPE cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.13:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.13:rc2:*:*:*:*:*:*
Summary
  • (es) En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: usb: gadget: u_serial: soluciona el problema por el cual gs_start_io se bloqueaba debido al acceso a un puntero nulo. Teniendo en cuenta que en algunos casos extremos, cuando varios subprocesos acceden al controlador u_serial, el subproceso A ejecuta la operación de apertura y llama a gs_open, el subproceso B ejecuta la operación de desconexión y llama a la función gserial_disconnect, el puntero port->port_usb se establecerá en NULL. P. ej. Hilo A Hilo B gs_open() gadget_unbind_driver() gs_start_io() composite_disconnect() gs_start_rx() gserial_disconnect() ... ... spin_unlock(&port->port_lock) status = usb_ep_queue() spin_lock(&port->port_lock) spin_lock(&port->port_lock) port->port_usb = NULL gs_free_requests(port->port_usb->in) spin_unlock(&port->port_lock) Bloqueo Esto hace que el hilo A acceda a un puntero nulo (port->port_usb es nulo) al llamar a la función gs_free_requests, lo que provoca un bloqueo. Si port_usb es NULL, se omitirá la solicitud de liberación, ya que la realizará gserial_disconnect. Por lo tanto, agregue una verificación de puntero nulo a gs_start_io antes de intentar acceder al valor del puntero port->port_usb. Rastreo de llamadas: gs_start_io+0x164/0x25c gs_open+0x108/0x13c tty_open+0x314/0x638 chrdev_open+0x1b8/0x258 do_dentry_open+0x2c4/0x700 vfs_open+0x2c/0x3c path_openat+0xa64/0xc60 do_filp_open+0xb8/0x164 do_sys_openat2+0x84/0xf0 __arm64_sys_openat+0x70/0x9c invocar_syscall+0x58/0x114 el0_svc_common+0x80/0xe0 do_el0_svc+0x1c/0x28 el0_svc+0x38/0x68
References () https://git.kernel.org/stable/c/1247e1df086aa6c17ab53cd1bedce70dd7132765 - () https://git.kernel.org/stable/c/1247e1df086aa6c17ab53cd1bedce70dd7132765 - Patch
References () https://git.kernel.org/stable/c/28b3c03a6790de1f6f2683919ad657840f0f0f58 - () https://git.kernel.org/stable/c/28b3c03a6790de1f6f2683919ad657840f0f0f58 - Patch
References () https://git.kernel.org/stable/c/4cfbca86f6a8b801f3254e0e3c8f2b1d2d64be2b - () https://git.kernel.org/stable/c/4cfbca86f6a8b801f3254e0e3c8f2b1d2d64be2b - Patch
References () https://git.kernel.org/stable/c/4efdfdc32d8d6307f968cd99f1db64468471bab1 - () https://git.kernel.org/stable/c/4efdfdc32d8d6307f968cd99f1db64468471bab1 - Patch
References () https://git.kernel.org/stable/c/8ca07a3d18f39b1669927ef536e485787e856df6 - () https://git.kernel.org/stable/c/8ca07a3d18f39b1669927ef536e485787e856df6 - Patch
References () https://git.kernel.org/stable/c/c83213b6649d22656b3a4e92544ceeea8a2c6c07 - () https://git.kernel.org/stable/c/c83213b6649d22656b3a4e92544ceeea8a2c6c07 - Patch
References () https://git.kernel.org/stable/c/dd6b0ca6025f64ccb465a6a3460c5b0307ed9c44 - () https://git.kernel.org/stable/c/dd6b0ca6025f64ccb465a6a3460c5b0307ed9c44 - Patch
First Time Linux linux Kernel
Linux
CWE CWE-476

27 Dec 2024, 15:15

Type Values Removed Values Added
New CVE

Information

Published : 2024-12-27 15:15

Updated : 2025-01-06 18:13


NVD link : CVE-2024-56670

Mitre link : CVE-2024-56670

CVE.ORG link : CVE-2024-56670


JSON object : View

Products Affected

linux

  • linux_kernel
CWE
CWE-476

NULL Pointer Dereference