LoongArch: BPF: Move arena register slot below TCC context
Currently, the stack layout places the optional arena register slot
above the tail call counter context. When arena_vm_start is dynamically
enabled, it shifts the relative offset of the tcc_ptr slot within the
stack frame, causing hardcoded tracking macros to mismatch and leading
to memory misalignment or corruption potentially.
To fix this, move the arena register save and restore sequences below
the tail call counter context slots in both build_prologue() and the
epilogue.
Update __build_epilogue() to insert a proper offset decrement to safely
skip the unneeded tcc_ptr reading block while accurately aligning with
the relocated arena slot at the very bottom.
With this patch, the tcc_ptr slot is always positioned at a fixed
distance directly underneath the base callee-saved registers that is
independent of whether the arena features are on.
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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Wed, 16 Sep 2026 10:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: LoongArch: BPF: Move arena register slot below TCC context Currently, the stack layout places the optional arena register slot above the tail call counter context. When arena_vm_start is dynamically enabled, it shifts the relative offset of the tcc_ptr slot within the stack frame, causing hardcoded tracking macros to mismatch and leading to memory misalignment or corruption potentially. To fix this, move the arena register save and restore sequences below the tail call counter context slots in both build_prologue() and the epilogue. Update __build_epilogue() to insert a proper offset decrement to safely skip the unneeded tcc_ptr reading block while accurately aligning with the relocated arena slot at the very bottom. With this patch, the tcc_ptr slot is always positioned at a fixed distance directly underneath the base callee-saved registers that is independent of whether the arena features are on. | |
| Title | LoongArch: BPF: Move arena register slot below TCC context | |
| 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: 2026-09-16T10:32:04.470Z
Reserved: 2026-09-11T19:38:34.774Z
Link: CVE-2026-89905
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-09-16T11:16:59.483
Modified: 2026-09-16T11:16:59.483
Link: CVE-2026-89905
Redhat
No data.
OpenCVE Enrichment
No data.
No weakness.