CVE-2021-47383

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Source
https://nvd.nist.gov/vuln/detail/CVE-2021-47383
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-47383.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2021-47383
Related
Published
2024-05-21T15:15:23Z
Modified
2024-09-18T03:17:27.227749Z
Summary
[none]
Details

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 FBIOPUTVSCREENINFO passing the fbvarscreeninfo struct containing only the fields xres, yres, and bitsper_pixel with values.

If this struct is the same as the previous ioctl, the vcresize() detects it and doesn't call the resizescreen(), leaving the fbvarscreeninfo incomplete. And this leads to the updatescrollmode() calculates a wrong value to fbcondisplay->vrows, which makes the realy() 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 resizescreen() be called even if the screen does not need any resizing, so it will "fix and fill" the fbvar_screeninfo independently.

References

Affected packages

Debian:11 / linux

Package

Name
linux
Purl
pkg:deb/debian/linux?arch=source

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
5.10.84-1

Affected versions

5.*

5.10.46-4
5.10.46-5
5.10.70-1~bpo10+1
5.10.70-1

Ecosystem specific 

{
    "urgency": "not yet assigned"
}

Debian:12 / linux

Package

Name
linux
Purl
pkg:deb/debian/linux?arch=source

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
5.14.12-1

Ecosystem specific 

{
    "urgency": "not yet assigned"
}

Debian:13 / linux

Package

Name
linux
Purl
pkg:deb/debian/linux?arch=source

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
5.14.12-1

Ecosystem specific 

{
    "urgency": "not yet assigned"
}