CVE-2026-89905

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.

CVSS

No CVSS.

References

Link	Resource
https://git.kernel.org/stable/c/cd7e356b07a27e91394838cf3fb655862b519294
https://git.kernel.org/stable/c/f0e4d069cb47cf4f8dc4f6bc104e0671155aa3b9

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-16 11:16

Updated : 2026-09-16 11:16

NVD link : CVE-2026-89905

Mitre link : CVE-2026-89905

CVE.ORG link : CVE-2026-89905

JSON object : View

Products Affected

No product.

CWE

No CWE.

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