🔍 CVE-2022-50701

7.1
CVSS Score
HIGH
2025-12-24
2026-10-15 22:17
✅ 완료

🇰🇷 한글 설명

Linux 커널의 mt76 드라이버 내 mt7921s 모듈에서 SDIO 버스 정렬을 위해 추가적인 공간이 필요한 상황에서 발생합니다. skb(socket buffer)의 tailroom이 충분하지 않을 경우 유효하지 않은 메모리 영역에 접근하는 slab-out-of-bounds 취약점이 존재합니다.

💡 쉬운 설명

무선 랜 카드가 데이터를 주고받을 때 필요한 메모리 공간을 충분히 확보하지 못해, 허용되지 않은 메모리 영역을 건드리는 오류입니다. 이로 인해 시스템이 멈추거나 보안 문제가 발생할 수 있습니다.

🇺🇸 원문 (English)

In the Linux kernel, the following vulnerability has been resolved: wifi: mt76: mt7921s: fix slab-out-of-bounds access in sdio host SDIO may need addtional 511 bytes to align bus operation. If the tailroom of this skb is not big enough, we would access invalid memory region. For low level operation, increase skb size to keep valid memory access in SDIO host. Error message: [69.951] BUG: KASAN: slab-out-of-bounds in sg_copy_buffer+0xe9/0x1a0 [69.951] Read of size 64 at addr ffff88811c9cf000 by task kworker/u16:7/451 [69.951] CPU: 4 PID: 451 Comm: kworker/u16:7 Tainted: G W OE 6.1.0-rc5 #1 [69.951] Workqueue: kvub300c vub300_cmndwork_thread [vub300] [69.951] Call Trace: [69.951] <TASK> [69.952] dump_stack_lvl+0x49/0x63 [69.952] print_report+0x171/0x4a8 [69.952] kasan_report+0xb4/0x130 [69.952] kasan_check_range+0x149/0x1e0 [69.952] memcpy+0x24/0x70 [69.952] sg_copy_buffer+0xe9/0x1a0 [69.952] sg_copy_to_buffer+0x12/0x20 [69.952] __command_write_data.isra.0+0x23c/0xbf0 [vub300] [69.952] vub300_cmndwork_thread+0x17f3/0x58b0 [vub300] [69.952] process_one_work+0x7ee/0x1320 [69.952] worker_thread+0x53c/0x1240 [69.952] kthread+0x2b8/0x370 [69.952] ret_from_fork+0x1f/0x30 [69.952] </TASK> [69.952] Allocated by task 854: [69.952] kasan_save_stack+0x26/0x50 [69.952] kasan_set_track+0x25/0x30 [69.952] kasan_save_alloc_info+0x1b/0x30 [69.952] __kasan_kmalloc+0x87/0xa0 [69.952] __kmalloc_node_track_caller+0x63/0x150 [69.952] kmalloc_reserve+0x31/0xd0 [69.952] __alloc_skb+0xfc/0x2b0 [69.952] __mt76_mcu_msg_alloc+0xbf/0x230 [mt76] [69.952] mt76_mcu_send_and_get_msg+0xab/0x110 [mt76] [69.952] __mt76_mcu_send_firmware.cold+0x94/0x15d [mt76] [69.952] mt76_connac_mcu_send_ram_firmware+0x415/0x54d [mt76_connac_lib] [69.952] mt76_connac2_load_ram.cold+0x118/0x4bc [mt76_connac_lib] [69.952] mt7921_run_firmware.cold+0x2e9/0x405 [mt7921_common] [69.952] mt7921s_mcu_init+0x45/0x80 [mt7921s] [69.953] mt7921_init_work+0xe1/0x2a0 [mt7921_common] [69.953] process_one_work+0x7ee/0x1320 [69.953] worker_thread+0x53c/0x1240 [69.953] kthread+0x2b8/0x370 [69.953] ret_from_fork+0x1f/0x30 [69.953] The buggy address belongs to the object at ffff88811c9ce800 which belongs to the cache kmalloc-2k of size 2048 [69.953] The buggy address is located 0 bytes to the right of 2048-byte region [ffff88811c9ce800, ffff88811c9cf000) [69.953] Memory state around the buggy address: [69.953] ffff88811c9cef00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [69.953] ffff88811c9cef80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [69.953] >ffff88811c9cf000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [69.953] ^ [69.953] ffff88811c9cf080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [69.953] ffff88811c9cf100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc

📍 영향받는 시스템

Linux kernel (mt76/mt7921s driver components)

⚔️ 공격 벡터

악의적으로 조작된 SDIO 버스 통신 패킷을 통해 메모리 경계를 넘어서는 접근 유도

🛡️ 대응 방법

Linux 커널을 최신 보안 패치가 적용된 버전으로 업데이트하여 skb 크기 할당 로직 수정

🔧 검증 코드

현재 실행 중인 커널 버전을 확인하여 취약점이 해결된 패치 버전인지 확인합니다.

Shell / Script
uname -r

📊 CVSS Vector String

CVSS Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

💻 영향받는 소프트웨어

Linux Kernel