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.
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.
Metrics
Affected Vendors & Products
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Thu, 17 Sep 2026 16:30:00 +0000
| Type | Values Removed | Values 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. | |
| Title | lib/test_hmm: fail dmirror_fault() when the mirrored mm is gone | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
|
Projects
Sign in to view the affected projects.
MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-09-17T16:09:25.083Z
Reserved: 2026-09-11T19:38:34.810Z
Link: CVE-2026-90391
Vulnrichment
No data.
NVD
No data.
Redhat
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.