CVE-2025-38169 (GCVE-0-2025-38169)
Vulnerability from cvelistv5
Published
2025-07-03 08:36
Modified
2026-10-15 21:52
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: arm64/fpsimd: Avoid clobbering kernel FPSIMD state with SMSTOP On system with SME, a thread's kernel FPSIMD state may be erroneously clobbered during a context switch immediately after that state is restored. Systems without SME are unaffected. If the CPU happens to be in streaming SVE mode before a context switch to a thread with kernel FPSIMD state, fpsimd_thread_switch() will restore the kernel FPSIMD state using fpsimd_load_kernel_state() while the CPU is still in streaming SVE mode. When fpsimd_thread_switch() subsequently calls fpsimd_flush_cpu_state(), this will execute an SMSTOP, causing an exit from streaming SVE mode. The exit from streaming SVE mode will cause the hardware to reset a number of FPSIMD/SVE/SME registers, clobbering the FPSIMD state. Fix this by calling fpsimd_flush_cpu_state() before restoring the kernel FPSIMD state.
References
Impacted products
Vendor Product Version
Linux Linux Version: e92bee9f861b466c676f0200be3e46af7bc4ac6b
Version: e92bee9f861b466c676f0200be3e46af7bc4ac6b
Version: e92bee9f861b466c676f0200be3e46af7bc4ac6b
Version: e003c485ac82a9f8de4204912ed059ac6dd4257c
Version: 25b90cd122d546823da90b916f7c3289dfe83a99
Version: 6.8.12   ≤
Version: 6.9.3   ≤
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