0.0
NA
CVE-2022-49978
Linux Kernel fbdev Divide by Zero Error
Description

In the Linux kernel, the following vulnerability has been resolved: fbdev: fb_pm2fb: Avoid potential divide by zero error In `do_fb_ioctl()` of fbmem.c, if cmd is FBIOPUT_VSCREENINFO, var will be copied from user, then go through `fb_set_var()` and `info->fbops->fb_check_var()` which could may be `pm2fb_check_var()`. Along the path, `var->pixclock` won't be modified. This function checks whether reciprocal of `var->pixclock` is too high. If `var->pixclock` is zero, there will be a divide by zero error. So, it is necessary to check whether denominator is zero to avoid crash. As this bug is found by Syzkaller, logs are listed below. divide error in pm2fb_check_var Call Trace: <TASK> fb_set_var+0x367/0xeb0 drivers/video/fbdev/core/fbmem.c:1015 do_fb_ioctl+0x234/0x670 drivers/video/fbdev/core/fbmem.c:1110 fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1189

INFO

Published Date :

June 18, 2025, 11:15 a.m.

Last Modified :

June 18, 2025, 1:46 p.m.

Remotely Exploit :

No

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products

The following products are affected by CVE-2022-49978 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Linux linux_kernel
: Total Affected Vendor : 1 | Products : 1
Solution
Follow the instructions below to mitigate the CVE-2022-49978 vulnerability.
There is no known solution at this time.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2022-49978.

URL Resource
https://git.kernel.org/stable/c/0f1174f4972ea9fad6becf8881d71adca8e9ca91
https://git.kernel.org/stable/c/19f953e7435644b81332dd632ba1b2d80b1e37af
https://git.kernel.org/stable/c/34c3dea1189525cd533071ed5c176fc4ea8d982b
https://git.kernel.org/stable/c/3ec326a6a0d4667585ca595f438c7293e5ced7c4
https://git.kernel.org/stable/c/7d9591b32a9092fc6391a316b56e8016c6181c3d
https://git.kernel.org/stable/c/7f88cdfea8d7f4dbaf423d808241403b2bb945e4
https://git.kernel.org/stable/c/8fc778ee2fb2853f7a3531fa7273349640d8e4e9
https://git.kernel.org/stable/c/cb4bb011a683532841344ca7f281b5e04389b4f8
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2022-49978 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2022-49978 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2022-49978 vulnerability anywhere in the article.

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2022-49978 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Jun. 18, 2025

    Action Type Old Value New Value
    Added Description In the Linux kernel, the following vulnerability has been resolved: fbdev: fb_pm2fb: Avoid potential divide by zero error In `do_fb_ioctl()` of fbmem.c, if cmd is FBIOPUT_VSCREENINFO, var will be copied from user, then go through `fb_set_var()` and `info->fbops->fb_check_var()` which could may be `pm2fb_check_var()`. Along the path, `var->pixclock` won't be modified. This function checks whether reciprocal of `var->pixclock` is too high. If `var->pixclock` is zero, there will be a divide by zero error. So, it is necessary to check whether denominator is zero to avoid crash. As this bug is found by Syzkaller, logs are listed below. divide error in pm2fb_check_var Call Trace: <TASK> fb_set_var+0x367/0xeb0 drivers/video/fbdev/core/fbmem.c:1015 do_fb_ioctl+0x234/0x670 drivers/video/fbdev/core/fbmem.c:1110 fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1189
    Added Reference https://git.kernel.org/stable/c/0f1174f4972ea9fad6becf8881d71adca8e9ca91
    Added Reference https://git.kernel.org/stable/c/19f953e7435644b81332dd632ba1b2d80b1e37af
    Added Reference https://git.kernel.org/stable/c/34c3dea1189525cd533071ed5c176fc4ea8d982b
    Added Reference https://git.kernel.org/stable/c/3ec326a6a0d4667585ca595f438c7293e5ced7c4
    Added Reference https://git.kernel.org/stable/c/7d9591b32a9092fc6391a316b56e8016c6181c3d
    Added Reference https://git.kernel.org/stable/c/7f88cdfea8d7f4dbaf423d808241403b2bb945e4
    Added Reference https://git.kernel.org/stable/c/8fc778ee2fb2853f7a3531fa7273349640d8e4e9
    Added Reference https://git.kernel.org/stable/c/cb4bb011a683532841344ca7f281b5e04389b4f8
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
No CVSS metrics available for this vulnerability.