Description
In the Linux kernel, the following vulnerability has been resolved:
ocfs2: fix use-after-free in ocfs2_fault() when VM_FAULT_RETRY
filemap_fault() may drop the mmap_lock before returning VM_FAULT_RETRY,
as documented in mm/filemap.c:
"If our return value has VM_FAULT_RETRY set, it's because the mmap_lock
may be dropped before doing I/O or by lock_folio_maybe_drop_mmap()."
When this happens, a concurrent munmap() can call remove_vma() and free
the vm_area_struct via RCU. The saved 'vma' pointer in ocfs2_fault() then
becomes a dangling pointer, and the subsequent trace_ocfs2_fault() call
dereferences it -- a use-after-free.
Fix this by saving ip_blkno as a plain integer before calling
filemap_fault(), and removing vma from the trace event. Since
ip_blkno is copied by value before the lock can be dropped, it
remains valid regardless of what happens to the vma or inode
afterward.
ocfs2: fix use-after-free in ocfs2_fault() when VM_FAULT_RETRY
filemap_fault() may drop the mmap_lock before returning VM_FAULT_RETRY,
as documented in mm/filemap.c:
"If our return value has VM_FAULT_RETRY set, it's because the mmap_lock
may be dropped before doing I/O or by lock_folio_maybe_drop_mmap()."
When this happens, a concurrent munmap() can call remove_vma() and free
the vm_area_struct via RCU. The saved 'vma' pointer in ocfs2_fault() then
becomes a dangling pointer, and the subsequent trace_ocfs2_fault() call
dereferences it -- a use-after-free.
Fix this by saving ip_blkno as a plain integer before calling
filemap_fault(), and removing vma from the trace event. Since
ip_blkno is copied by value before the lock can be dropped, it
remains valid regardless of what happens to the vma or inode
afterward.
Published:
2026-04-24
Score:
n/a
EPSS:
n/a
KEV:
No
Impact:
n/a
Action:
n/a
Analysis
No analysis available yet.
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Linux | Linux | unaffected |
|
|||||||||||||||
| Linux | Linux | affected |
|
No data.
No data.
No data available yet.
Remediation
No remediation available yet.
Tracking
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Advisories
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References
History
Sat, 25 Apr 2026 00:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Weaknesses | CWE-364 | |
| References |
|
Fri, 24 Apr 2026 15:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix use-after-free in ocfs2_fault() when VM_FAULT_RETRY filemap_fault() may drop the mmap_lock before returning VM_FAULT_RETRY, as documented in mm/filemap.c: "If our return value has VM_FAULT_RETRY set, it's because the mmap_lock may be dropped before doing I/O or by lock_folio_maybe_drop_mmap()." When this happens, a concurrent munmap() can call remove_vma() and free the vm_area_struct via RCU. The saved 'vma' pointer in ocfs2_fault() then becomes a dangling pointer, and the subsequent trace_ocfs2_fault() call dereferences it -- a use-after-free. Fix this by saving ip_blkno as a plain integer before calling filemap_fault(), and removing vma from the trace event. Since ip_blkno is copied by value before the lock can be dropped, it remains valid regardless of what happens to the vma or inode afterward. | |
| Title | ocfs2: fix use-after-free in ocfs2_fault() when VM_FAULT_RETRY | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-04-24T14:42:22.655Z
Reserved: 2026-03-09T15:48:24.121Z
Link: CVE-2026-31597
Vulnrichment
No data.
NVD
Status : Awaiting Analysis
Published: 2026-04-24T15:16:37.457
Modified: 2026-04-24T17:51:40.810
Link: CVE-2026-31597
Redhat
OpenCVE Enrichment
No data.
Weaknesses