🔍 CVE-2026-31562

5.5
CVSS Score
MEDIUM
2026-04-24
2026-10-21 13:18
✅ 완료

🇰🇷 한글 설명

Linux 커널의 drm/mediatek: dsi 드라이버에서 mipi_dsi_host_register 호출 전 드라이버 데이터를 저장하지 않아 발생하는 취약점입니다. 이로 인해 초기화되지 않은 drvdata를 참조하게 되어 커널 NULL 포인터 역참조 및 시스템 크래시가 발생할 수 있습니다.

💡 쉬운 설명

기기 화면을 제어하는 소프트웨어가 준비되지 않은 상태에서 정보를 불러오려다 시스템이 멈추는 오류입니다. 이로 인해 기기가 갑자기 꺼지거나 작동을 멈출 수 있습니다.

🇺🇸 원문 (English)

In the Linux kernel, the following vulnerability has been resolved: drm/mediatek: dsi: Store driver data before invoking mipi_dsi_host_register The call to mipi_dsi_host_register triggers a callback to mtk_dsi_bind, which uses dev_get_drvdata to retrieve the mtk_dsi struct, so this structure needs to be stored inside the driver data before invoking it. As drvdata is currently uninitialized it leads to a crash when registering the DSI DRM encoder right after acquiring the mode_config.idr_mutex, blocking all subsequent DRM operations. Fixes the following crash during mediatek-drm probe (tested on Xiaomi Smart Clock x04g): Unable to handle kernel NULL pointer dereference at virtual address 0000000000000040 [...] Modules linked in: mediatek_drm(+) drm_display_helper cec drm_client_lib drm_dma_helper drm_kms_helper panel_simple [...] Call trace: drm_mode_object_add+0x58/0x98 (P) __drm_encoder_init+0x48/0x140 drm_encoder_init+0x6c/0xa0 drm_simple_encoder_init+0x20/0x34 [drm_kms_helper] mtk_dsi_bind+0x34/0x13c [mediatek_drm] component_bind_all+0x120/0x280 mtk_drm_bind+0x284/0x67c [mediatek_drm] try_to_bring_up_aggregate_device+0x23c/0x320 __component_add+0xa4/0x198 component_add+0x14/0x20 mtk_dsi_host_attach+0x78/0x100 [mediatek_drm] mipi_dsi_attach+0x2c/0x50 panel_simple_dsi_probe+0x4c/0x9c [panel_simple] mipi_dsi_drv_probe+0x1c/0x28 really_probe+0xc0/0x3dc __driver_probe_device+0x80/0x160 driver_probe_device+0x40/0x120 __device_attach_driver+0xbc/0x17c bus_for_each_drv+0x88/0xf0 __device_attach+0x9c/0x1cc device_initial_probe+0x54/0x60 bus_probe_device+0x34/0xa0 device_add+0x5b0/0x800 mipi_dsi_device_register_full+0xdc/0x16c mipi_dsi_host_register+0xc4/0x17c mtk_dsi_probe+0x10c/0x260 [mediatek_drm] platform_probe+0x5c/0xa4 really_probe+0xc0/0x3dc __driver_probe_device+0x80/0x160 driver_probe_device+0x40/0x120 __driver_attach+0xc8/0x1f8 bus_for_each_dev+0x7c/0xe0 driver_attach+0x24/0x30 bus_add_driver+0x11c/0x240 driver_register+0x68/0x130 __platform_register_drivers+0x64/0x160 mtk_drm_init+0x24/0x1000 [mediatek_drm] do_one_initcall+0x60/0x1d0 do_init_module+0x54/0x240 load_module+0x1838/0x1dc0 init_module_from_file+0xd8/0xf0 __arm64_sys_finit_module+0x1b4/0x428 invoke_syscall.constprop.0+0x48/0xc8 do_el0_svc+0x3c/0xb8 el0_svc+0x34/0xe8 el0t_64_sync_handler+0xa0/0xe4 el0t_64_sync+0x198/0x19c Code: 52800022 941004ab 2a0003f3 37f80040 (29005a80)

📍 영향받는 시스템

Linux kernel (MediaTek DRM driver components)

⚔️ 공격 벡터

Local/Physical (Kernel probe process during driver initialization)

🛡️ 대응 방법

Linux 커널을 최신 보안 패치가 적용된 버전으로 업데이트하십시오.

🔧 검증 코드

출력된 커널 버전이 해당 취약점이 수정된 패치 버전 이후인지 확인하십시오.

Shell / Script
uname -r

📊 CVSS Vector String

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

💻 영향받는 소프트웨어

Linux Kernel