From: Mark Rutland <mark.rutland@arm.com> mainline inclusion from mainline-6.16 commit a90878f297d3dba906a6261deccb1bd4a791ba52 category: bugfix bugzilla: https://atomgit.com/openeuler/kernel/issues/8904 CVE: NA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... ---------------------------------------------------------------------- An exec() is expected to reset all FPSIMD/SVE/SME state, and barring special handling of the vector lengths, the state is expected to reset to zero. This reset is handled in fpsimd_flush_thread(), which the core exec() code calls via flush_thread(). When support was added for FPMR, no logic was added to fpsimd_flush_thread() to reset the FPMR value, and thus it is erroneously inherited across an exec(). Add the missing reset of FPMR. Fixes: 203f2b95a882 ("arm64/fpsimd: Support FEAT_FPMR") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Mark Brown <broonie@kernel.org> Cc: Will Deacon <will@kernel.org> Reviewed-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20250409164010.3480271-9-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Qinxin Xia <xiaqinxin@huawei.com> Signed-off-by: Hongye Lin <linhongye@h-partners.com> --- arch/arm64/kernel/fpsimd.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index df20cabd60c3..3653c8ead31f 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -1688,6 +1688,9 @@ void fpsimd_flush_thread(void) current->thread.svcr = 0; } + if (system_supports_fpmr()) + current->thread.uw.fpmr = 0; + current->thread.fp_type = FP_STATE_FPSIMD; put_cpu_fpsimd_context(); -- 2.33.0