CVE-2026-90391
lib/test_hmm: fail dmirror_fault() when the mirrored mm is gone
Description
In the Linux kernel, the following vulnerability has been resolved: lib/test_hmm: fail dmirror_fault() when the mirrored mm is gone dmirror_fault() is called from the dmirror_read() and dmirror_write() retry loops after dmirror_do_read() or dmirror_do_write() finds a missing device page table entry. If the mirrored mm has already exited, mmget_not_zero() fails. The current code returns 0 in that case, which tells the caller that faulting succeeded even though no page was faulted and no device page table entry was installed. The caller then retries the same address, hits -ENOENT again, and can loop forever without making progress. Return -EFAULT instead, so the ioctl fails when the mirrored mm is no longer faultable.
INFO
Published Date :
Sept. 17, 2026, 5:17 p.m.
Last Modified :
Sept. 17, 2026, 5:17 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
- Update the Linux kernel to the latest version.
- Apply relevant security patches for the kernel.
- Recompile and install the updated kernel.
- Restart the system to load the new kernel.
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-2026-90391.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-90391 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-2026-90391
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-2026-90391 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-90391 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
Sep. 17, 2026
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: lib/test_hmm: fail dmirror_fault() when the mirrored mm is gone dmirror_fault() is called from the dmirror_read() and dmirror_write() retry loops after dmirror_do_read() or dmirror_do_write() finds a missing device page table entry. If the mirrored mm has already exited, mmget_not_zero() fails. The current code returns 0 in that case, which tells the caller that faulting succeeded even though no page was faulted and no device page table entry was installed. The caller then retries the same address, hits -ENOENT again, and can loop forever without making progress. Return -EFAULT instead, so the ioctl fails when the mirrored mm is no longer faultable. Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/90xxx/CVE-2026-90391.json">CVE-2026-90391</a> Added Reference https://git.kernel.org/stable/c/2636569ea7c19d9a40db4a1e8d0a027bdacf1569 Added Reference https://git.kernel.org/stable/c/50606ced303782f8715e2d0b98ca374ea498fa29 Added Reference https://git.kernel.org/stable/c/541a67f21ab807c8dbc0ea88d5a2eb73b2618090 Added Reference https://git.kernel.org/stable/c/6a8024511ddf4877435c34fb3d6028aa8e590649 Added Reference https://git.kernel.org/stable/c/701347e31aa607f3782403151a3125729d685275 Added Reference https://git.kernel.org/stable/c/a2074f86fc9653831e4fb7b711bb715db330f182 Added Reference https://git.kernel.org/stable/c/af7a6d6ec36a16a583ba2e4e9984c3cf1fe34655 Added Reference https://git.kernel.org/stable/c/d8e64ffab01e032ae29159d27230ace8cf8bdc80