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: commit 70f93dae32ac ("KVM: Use temporary variable to shorten lines.")
Signed-off-by: Nick Finco <nifi@xxxxxxxxxx>
Signed-off-by: Marios Pomonis <pomonis@xxxxxxxxxx>
Reviewed-by: Andrew Honig <ahonig@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
---
arch/x86/kvm/ioapic.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/x86/kvm/ioapic.c b/arch/x86/kvm/ioapic.c
index 0c672eefaabe..8aa58727045e 100644
--- a/arch/x86/kvm/ioapic.c
+++ b/arch/x86/kvm/ioapic.c
@@ -294,6 +294,7 @@ 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 */
--
2.24.0.525.g8f36a354ae-goog
