From: Joey Gouly <joey.gouly@xxxxxxx> [ Upstream commit e3e85271330b18f487ab3032ea9ca0601efeafaf ] Restrict kernel threads to only have RWX overlays for pkey 0. This matches what arch/x86 does, by defaulting to a restrictive PKRU. Signed-off-by: Joey Gouly <joey.gouly@xxxxxxx> Cc: Will Deacon <will@xxxxxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Reviewed-by: Kevin Brodsky <Kevin.Brodsky@xxxxxxx> Link: https://lore.kernel.org/r/20241001133618.1547996-2-joey.gouly@xxxxxxx Signed-off-by: Will Deacon <will@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- arch/arm64/kernel/process.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index 044a7d7f1f6ad..048fe09da8a07 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -399,6 +399,9 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) p->thread.cpu_context.x19 = (unsigned long)args->fn; p->thread.cpu_context.x20 = (unsigned long)args->fn_arg; + + if (system_supports_poe()) + p->thread.por_el0 = POR_EL0_INIT; } p->thread.cpu_context.pc = (unsigned long)ret_from_fork; p->thread.cpu_context.sp = (unsigned long)childregs; -- 2.43.0
