CVE-2026-74721
accel/amxdna: Fix page-insertion errors in amdxdna_insert_pages()
Description
In the Linux kernel, the following vulnerability has been resolved: accel/amxdna: Fix page-insertion errors in amdxdna_insert_pages() Two error paths in amdxdna_insert_pages() called vma->vm_ops->close(vma) before returning an error code to the caller. This is incorrect: amdxdna_gem_obj_mmap() registers an HMM interval notifier before calling amdxdna_insert_pages(), and on a hard error it jumps to hmm_unreg to undo that registration. Calling vm_ops->close() manually — which drops the shmem pages_pin_count and the GEM object reference that backs the VMA — before the mmap syscall has even returned causes those resources to be released while the VMA is still alive. The kernel VMA teardown will call vm_ops->close() a second time when the process later unmaps the range, producing a reference count underflow. Replace both hard-error returns with a deferred-fault approach that keeps the VMA alive and retries page insertion through the HMM range-fault path.
INFO
Published Date :
Aug. 22, 2026, 4:16 p.m.
Last Modified :
Aug. 22, 2026, 4:16 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
- Use deferred-fault for page insertion to keep VMA alive.
- Retry page insertion via HMM range-fault path on error.
- Ensure VMA resources are released only when VMA is dead.
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-2026-74721.
| URL | Resource |
|---|---|
| https://git.kernel.org/stable/c/1501e4d07c6fee0d50531a0d1cb2be01a63e6e75 | |
| https://git.kernel.org/stable/c/8d51e0fd3e698919d2adeff71936377f0c0d4aa0 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-74721 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-2026-74721
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-2026-74721 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-74721 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.
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New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 22, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'e486147c912f653ef4b60a6c7dbd4168a4c56a9f', 'lessThan': '1501e4d07c6fee0d50531a0d1cb2be01a63e6e75', 'versionType': 'git'}, {'status': 'affected', 'version': 'e486147c912f653ef4b60a6c7dbd4168a4c56a9f', 'lessThan': '8d51e0fd3e698919d2adeff71936377f0c0d4aa0', 'versionType': 'git'}], 'programFiles': ['drivers/accel/amdxdna/amdxdna_gem.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.16'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.16', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '7.1.9', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['drivers/accel/amdxdna/amdxdna_gem.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: accel/amxdna: Fix page-insertion errors in amdxdna_insert_pages() Two error paths in amdxdna_insert_pages() called vma->vm_ops->close(vma) before returning an error code to the caller. This is incorrect: amdxdna_gem_obj_mmap() registers an HMM interval notifier before calling amdxdna_insert_pages(), and on a hard error it jumps to hmm_unreg to undo that registration. Calling vm_ops->close() manually — which drops the shmem pages_pin_count and the GEM object reference that backs the VMA — before the mmap syscall has even returned causes those resources to be released while the VMA is still alive. The kernel VMA teardown will call vm_ops->close() a second time when the process later unmaps the range, producing a reference count underflow. Replace both hard-error returns with a deferred-fault approach that keeps the VMA alive and retries page insertion through the HMM range-fault path. Added Reference https://git.kernel.org/stable/c/1501e4d07c6fee0d50531a0d1cb2be01a63e6e75 Added Reference https://git.kernel.org/stable/c/8d51e0fd3e698919d2adeff71936377f0c0d4aa0