Description
In the Linux kernel, the following vulnerability has been resolved: tty: Fix out-of-bound vmalloc access in imageblit This issue happens when a userspace program does an ioctl FBIOPUT_VSCREENINFO passing the fb_var_screeninfo struct containing only the fields xres, yres, and bits_per_pixel with values. If this struct is the same as the previous ioctl, the vc_resize() detects it and doesn't call the resize_screen(), leaving the fb_var_screeninfo incomplete. And this leads to the updatescrollmode() calculates a wrong value to fbcon_display->vrows, which makes the real_y() return a wrong value of y, and that value, eventually, causes the imageblit to access an out-of-bound address value. To solve this issue I made the resize_screen() be called even if the screen does not need any resizing, so it will "fix and fill" the fb_var_screeninfo independently.
INFO
Published Date :
2024-05-21T15:03:44.286Z
Last Modified :
2025-12-18T11:37:17.172Z
Source :
Linux
AFFECTED PRODUCTS
The following products are affected by CVE-2021-47383 vulnerability.
| Vendors | Products |
|---|---|
| Linux |
|
| Redhat |
|
REFERENCES
Here, you will find a curated list of external links that provide in-depth information to CVE-2021-47383.