CVE-2021-47583: Linux Kernel

Medium severity, CVSS 5.5. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: media: mxl111sf: change mutex_init() location Syzbot reported, that mxl111sf_ctrl_msg() uses uninitialized mutex. The problem was in wrong mutex_init() location. Previous mutex_init(&state->msg_lock) call was in ->init() function, but dvb_usbv2_init() has this order of calls: dvb_usbv2_init() dvb_usbv2_adapter_init() dvb_usbv2_adapter_frontend_init() props->frontend_attach() props->init() Since mxl111sf_* devices call mxl111sf_ctrl_msg() in ->frontend_attach() internally we need to initialize state->msg_lock before frontend_attach(). To achieve it, ->probe() call added to all mxl111sf_* devices, which will simply initiaize mutex.

Affected products

• Linux Linux Kernel: from 3.7, before 4.19.222 (fixed in 4.19.222); from 4.20, before 5.4.168 (fixed in 5.4.168); from 5.5, before 5.10.88 (fixed in 5.10.88); from 5.11, before 5.15.11 (fixed in 5.15.11)

Published 2024-06-19. Last modified 2026-06-17.