CVSS7.8
Severityhigh
WeaknessCWE-401
ExploitedNot in CISA KEV
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Description
In the Linux kernel, the following vulnerability has been resolved: fbdev: defio: Disconnect deferred I/O from the lifetime of struct fb_info Hold state of deferred I/O in struct fb_deferred_io_state. Allocate an instance as part of initializing deferred I/O and remove it only after the final mapping has been closed. If the fb_info and the contained deferred I/O meanwhile goes away, clear struct fb_deferred_io_state.info to invalidate the mapping. Any access will then result in a SIGBUS signal. Fixes a long-standing problem, where a device hot-unplug happens while user space still has an active mapping of the graphics memory. The hot- unplug frees the instance of struct fb_info. Accessing