bpf: Reject arena frees below the arena base
bpf_arena_free_pages() accepts scalar arena addresses. The runtime
masks the address to the low 32 bits and reconstructs a full user
address from the arena base before returning the range to the arena
free tree.
When the scalar value is below the low 32 bits of the arena base,
full_uaddr falls below user_vm_start. The existing upper-end clipping
then turns this into an out-of-range free-tree offset. A later
allocation can reuse that offset and return an address below the arena
mapping.
Reject such frees before computing the clipped range.
Analysis
Analysis and contextual insights are available on OpenCVE Cloud.
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 |
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| Linux | Linux | affected |
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No data.
No data.
No data available yet.
No vendor fix or workaround currently provided.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
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Thu, 17 Sep 2026 16:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: bpf: Reject arena frees below the arena base bpf_arena_free_pages() accepts scalar arena addresses. The runtime masks the address to the low 32 bits and reconstructs a full user address from the arena base before returning the range to the arena free tree. When the scalar value is below the low 32 bits of the arena base, full_uaddr falls below user_vm_start. The existing upper-end clipping then turns this into an out-of-range free-tree offset. A later allocation can reuse that offset and return an address below the arena mapping. Reject such frees before computing the clipped range. | |
| Title | bpf: Reject arena frees below the arena base | |
| 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: 2026-09-17T16:10:36.988Z
Reserved: 2026-09-17T15:57:05.658Z
Link: CVE-2026-93045
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-09-17T17:17:57.743
Modified: 2026-09-17T17:17:57.743
Link: CVE-2026-93045
Redhat
No data.
OpenCVE Enrichment
No data.
No weakness.