CVE-2025-22020
Description
From CVE.org
In the Linux kernel, the following vulnerability has been resolved: memstick: rtsx_usb_ms: Fix slab-use-after-free in rtsx_usb_ms_drv_remove This fixes the following crash: ================================================================== BUG: KASAN: slab-use-after-free in rtsx_usb_ms_poll_card+0x159/0x200 [rtsx_usb_ms] Read of size 8 at addr ffff888136335380 by task kworker/6:0/140241 CPU: 6 UID: 0 PID: 140241 Comm: kworker/6:0 Kdump: loaded Tainted: G E 6.14.0-rc6+ #1 Tainted: [E]=UNSIGNED_MODULE Hardware name: LENOVO 30FNA1V7CW/1057, BIOS S0EKT54A 07/01/2024 Workqueue: events rtsx_usb_ms_poll_card [rtsx_usb_ms] Call Trace: <TASK> dump_stack_lvl+0x51/0x70 print_address_description.constprop.0+0x27/0x320 ? rtsx_usb_ms_poll_card+0x159/0x200 [rtsx_usb_ms] print_report+0x3e/0x70 kasan_report+0xab/0xe0 ? rtsx_usb_ms_poll_card+0x159/0x200 [rtsx_usb_ms] rtsx_usb_ms_poll_card+0x159/0x200 [rtsx_usb_ms] ? __pfx_rtsx_usb_ms_poll_card+0x10/0x10 [rtsx_usb_ms] ? __pfx___schedule+0x10/0x10 ? kick_pool+0x3b/0x270 process_one_work+0x357/0x660 worker_thread+0x390/0x4c0 ? __pfx_worker_thread+0x10/0x10 kthread+0x190/0x1d0 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x2d/0x50 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> Allocated by task 161446: kasan_save_stack+0x20/0x40 kasan_save_track+0x10/0x30 __kasan_kmalloc+0x7b/0x90 __kmalloc_noprof+0x1a7/0x470 memstick_alloc_host+0x1f/0xe0 [memstick] rtsx_usb_ms_drv_probe+0x47/0x320 [rtsx_usb_ms] platform_probe+0x60/0xe0 call_driver_probe+0x35/0x120 really_probe+0x123/0x410 __driver_probe_device+0xc7/0x1e0 driver_probe_device+0x49/0xf0 __device_attach_driver+0xc6/0x160 bus_for_each_drv+0xe4/0x160 __device_attach+0x13a/0x2b0 bus_probe_device+0xbd/0xd0 device_add+0x4a5/0x760 platform_device_add+0x189/0x370 mfd_add_device+0x587/0x5e0 mfd_add_devices+0xb1/0x130 rtsx_usb_probe+0x28e/0x2e0 [rtsx_usb] usb_probe_interface+0x15c/0x460 call_driver_probe+0x35/0x120 really_probe+0x123/0x410 __driver_probe_device+0xc7/0x1e0 driver_probe_device+0x49/0xf0 __device_attach_driver+0xc6/0x160 bus_for_each_drv+0xe4/0x160 __device_attach+0x13a/0x2b0 rebind_marked_interfaces.isra.0+0xcc/0x110 usb_reset_device+0x352/0x410 usbdev_do_ioctl+0xe5c/0x1860 usbdev_ioctl+0xa/0x20 __x64_sys_ioctl+0xc5/0xf0 do_syscall_64+0x59/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e Freed by task 161506: kasan_save_stack+0x20/0x40 kasan_save_track+0x10/0x30 kasan_save_free_info+0x36/0x60 __kasan_slab_free+0x34/0x50 kfree+0x1fd/0x3b0 device_release+0x56/0xf0 kobject_cleanup+0x73/0x1c0 rtsx_usb_ms_drv_remove+0x13d/0x220 [rtsx_usb_ms] platform_remove+0x2f/0x50 device_release_driver_internal+0x24b/0x2e0 bus_remove_device+0x124/0x1d0 device_del+0x239/0x530 platform_device_del.part.0+0x19/0xe0 platform_device_unregister+0x1c/0x40 mfd_remove_devices_fn+0x167/0x170 device_for_each_child_reverse+0xc9/0x130 mfd_remove_devices+0x6e/0xa0 rtsx_usb_disconnect+0x2e/0xd0 [rtsx_usb] usb_unbind_interface+0xf3/0x3f0 device_release_driver_internal+0x24b/0x2e0 proc_disconnect_claim+0x13d/0x220 usbdev_do_ioctl+0xb5e/0x1860 usbdev_ioctl+0xa/0x20 __x64_sys_ioctl+0xc5/0xf0 do_syscall_64+0x59/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e Last potentially related work creation: kasan_save_stack+0x20/0x40 kasan_record_aux_stack+0x85/0x90 insert_work+0x29/0x100 __queue_work+0x34a/0x540 call_timer_fn+0x2a/0x160 expire_timers+0x5f/0x1f0 __run_timer_base.part.0+0x1b6/0x1e0 run_timer_softirq+0x8b/0xe0 handle_softirqs+0xf9/0x360 __irq_exit_rcu+0x114/0x130 sysvec_apic_timer_interrupt+0x72/0x90 asm_sysvec_apic_timer_interrupt+0x16/0x20 Second to last potentially related work creation: kasan_save_stack+0x20/0x40 kasan_record_aux_stack+0x85/0x90 insert_work+0x29/0x100 __queue_work+0x34a/0x540 call_timer_fn+0x2a/0x160 expire_timers+0x5f/0x1f0 __run_timer_base.part.0+0x1b6/0x1e0 run_timer_softirq+0x8b/0xe0 handle_softirqs+0xf9/0x ---truncated---
Statement
This vulnerability is caused by a race condition between the driver removal routine and a periodically scheduled work function (poll_card). It can be triggered by attaching and then removing a USB device, which in turn calls the removal subroutine, which runs before ensuring that the poll_card work item is canceled.
If done physically, then the attack requires no particular user privileges. However, implementing a programmatic version of this vulnerability would require elevated privileges (e.g. CAP_SYS_ADMIN) as it would require driver unbinding and/or device removal.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.8 | 7.8 | 7.8 |
| Attack Vector | Local | Local | Local |
| Attack Complexity | Low | Low | Low |
| Privileges Required | Low | Low | Low |
| User Interaction | None | None | None |
| Scope | Unchanged | Unchanged | Unchanged |
| Confidentiality | High | High | High |
| Integrity Impact | High | High | High |
| Availability Impact | High | High | High |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
cve.org: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Understanding the Weakness (CWE)
Integrity
Technical Impact: Modify Memory
The use of previously freed memory may corrupt valid data, if the memory area in question has been allocated and used properly elsewhere.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
If chunk consolidation occurs after the use of previously freed data, the process may crash when invalid data is used as chunk information.
Confidentiality
Technical Impact: Read Memory
Read operations on freed memory can sometimes leak sensitive information instead of causing a crash
Integrity,Confidentiality,Availability
Technical Impact: Execute Unauthorized Code or Commands
If malicious data is entered before chunk consolidation can take place, it may be possible to take advantage of a write-what-where primitive to execute arbitrary code. If the newly allocated data happens to hold a class, in C++ for example, various function pointers may be scattered within the heap data. If one of these function pointers is overwritten with an address to valid shellcode, execution of arbitrary code can be achieved.
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
