Commit 480ea48c authored by Sebastian Ene's avatar Sebastian Ene Committed by Marc Zyngier
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KVM: arm64: Reject non compliant SMCCC function calls in pKVM 



Prevent the propagation of a function-id that has the top bits set since
this is not compliant with the SMCCC spec and can overlap with the
already known function-id decoders. (eg. if we invoke an smc with
0xffffffffc4000012 it will be decoded as a PSCI reset call). Instead,
make it clear that we don't support it and return an error.

Signed-off-by: default avatarSebastian Ene <sebastianene@google.com>
Link: https://patch.msgid.link/20260408114118.422604-1-sebastianene@google.com


Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
parent a0e6ae45

arch/arm64/kvm/hyp/nvhe/hyp-main.c

+4 −0
Original line number Diff line number Diff line
@@ -805,6 +805,10 @@ static void handle_host_smc(struct kvm_cpu_context *host_ctxt) 
	}



	func_id &= ~ARM_SMCCC_CALL_HINTS;

	if (upper_32_bits(func_id)) {

		cpu_reg(host_ctxt, 0) = SMCCC_RET_NOT_SUPPORTED;

		goto exit_skip_instr;

	}



	handled = kvm_host_psci_handler(host_ctxt, func_id);

	if (!handled)