| Name | CVE-2021-47383 |
| 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. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| linux (PTS) | jessie, jessie (lts) | 3.16.84-1 | vulnerable |
| stretch (security) | 4.9.320-2 | vulnerable | |
| stretch (lts), stretch | 4.9.320-3 | vulnerable | |
| buster (security), buster, buster (lts) | 4.19.316-1 | fixed | |
| bullseye | 5.10.223-1 | fixed | |
| bullseye (security) | 5.10.226-1 | fixed | |
| bookworm | 6.1.115-1 | fixed | |
| bookworm (security) | 6.1.112-1 | fixed | |
| trixie | 6.11.7-1 | fixed | |
| sid | 6.11.9-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| linux | source | jessie | (unfixed) | end-of-life | ||
| linux | source | stretch | (unfixed) | end-of-life | ||
| linux | source | buster | 4.19.232-1 | |||
| linux | source | bullseye | 5.10.84-1 | |||
| linux | source | (unstable) | 5.14.12-1 |
https://git.kernel.org/linus/3b0c406124719b625b1aba431659f5cdc24a982c (5.15-rc1)