CVE-2025-38586 Information

Aug 20, 2025 cve

Description

In the Linux kernel the following vulnerability has been resolved:

bpf arm64: Fix fp initialization for exception boundary

In the ARM64 BPF JIT when prog->aux->exception_boundary is set for a BPF program find_used_callee_regs() is not called because for a program acting as exception boundary all callee saved registers are saved. find_used_callee_regs() sets ctx->fp_used = true; when it sees FP being used in any of the instructions.

For programs acting as exception boundary ctx->fp_used remains false even if frame pointer is used by the program and therefore FP is not set-up for such programs in the prologue. This can cause the kernel to crash due to a pagefault.

Fix it by setting ctx->fp_used = true for exception boundary programs as fp is always saved in such programs.

Reference

https://git.kernel.org/stable/c/0dbef493cae7d451f740558665893c000adb2321 https://git.kernel.org/stable/c/1ce30231e0a2c8c361ee5f8f7f265fc17130adce https://git.kernel.org/stable/c/b114fcee766d5101eada1aca7bb5fd0a86c89b35 https://git.kernel.org/stable/c/e23184725dbb72d5d02940222eee36dbba2aa422

CNNVD-202508-2150 (Published: 2025-08-19)

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