CVE-2022-39842medium
Description
** DISPUTED ** An issue was discovered in the Linux kernel before 5.19. In pxa3xx_gcu_write in drivers/video/fbdev/pxa3xx-gcu.c, the count parameter has a type conflict of size_t versus int, causing an integer overflow and bypassing the size check. After that, because it is used as the third argument to copy_from_user(), a heap overflow may occur. NOTE: the original discoverer disputes that the overflow can actually happen.
References
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.19
https://github.com/torvalds/linux/commit/a09d2d00af53b43c6f11e6ab3cb58443c2cac8a7
https://lists.debian.org/debian-lts-announce/2022/10/msg00000.html
https://www.debian.org/security/2022/dsa-5257
https://lists.debian.org/debian-lts-announce/2022/11/msg00001.html