Commit 67056455 authored by Marios Pomonis's avatar Marios Pomonis Committed by Paolo Bonzini
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KVM: x86: Protect ioapic_write_indirect() from Spectre-v1/L1TF attacks 



This fixes a Spectre-v1/L1TF vulnerability in ioapic_write_indirect().
This function contains index computations based on the
(attacker-controlled) IOREGSEL register.

This patch depends on patch
"KVM: x86: Protect ioapic_read_indirect() from Spectre-v1/L1TF attacks".

Fixes: 70f93dae ("KVM: Use temporary variable to shorten lines.")

Signed-off-by: default avatarNick Finco <nifi@google.com>
Signed-off-by: default avatarMarios Pomonis <pomonis@google.com>
Reviewed-by: default avatarAndrew Honig <ahonig@google.com>
Cc: stable@vger.kernel.org
Reviewed-by: default avatarJim Mattson <jmattson@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 8c86405f

arch/x86/kvm/ioapic.c

+1 −0
Original line number Diff line number Diff line
@@ -297,6 +297,7 @@ static void ioapic_write_indirect(struct kvm_ioapic *ioapic, u32 val) 


		if (index >= IOAPIC_NUM_PINS)

			return;

		index = array_index_nospec(index, IOAPIC_NUM_PINS);

		e = &ioapic->redirtbl[index];

		mask_before = e->fields.mask;

		/* Preserve read-only fields */