Patch "KVM: arm/arm64: vgic: Avoid injecting reserved IRQ numbers" has been added to the 4.1-stable tree

Patch "KVM: arm/arm64: vgic: Avoid injecting reserved IRQ numbers" has been added to the 4.1-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    KVM: arm/arm64: vgic: Avoid injecting reserved IRQ numbers

to the 4.1-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     kvm-arm-arm64-vgic-avoid-injecting-reserved-irq-numbers.patch
and it can be found in the queue-4.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 4839ddc27b7212ec58874f62c97da7400c8523be Mon Sep 17 00:00:00 2001
From: Marc Zyngier <marc.zyngier@arm.com>
Date: Wed, 17 Jun 2015 14:43:35 +0100
Subject: KVM: arm/arm64: vgic: Avoid injecting reserved IRQ numbers

From: Marc Zyngier <marc.zyngier@arm.com>

commit 4839ddc27b7212ec58874f62c97da7400c8523be upstream.

Commit fd1d0ddf2ae9 (KVM: arm/arm64: check IRQ number on userland
injection) rightly limited the range of interrupts userspace can
inject in a guest, but failed to consider the (unlikely) case where
a guest is configured with 1024 interrupts.

In this case, interrupts ranging from 1020 to 1023 are unuseable,
as they have a special meaning for the GIC CPU interface.

Make sure that these number cannot be used as an IRQ. Also delete
a redundant (and similarily buggy) check in kvm_set_irq.

Reported-by: Peter Maydell <peter.maydell@linaro.org>
Cc: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 virt/kvm/arm/vgic.c |    5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

--- a/virt/kvm/arm/vgic.c
+++ b/virt/kvm/arm/vgic.c
@@ -1561,7 +1561,7 @@ int kvm_vgic_inject_irq(struct kvm *kvm,
 			goto out;
 	}
 
-	if (irq_num >= kvm->arch.vgic.nr_irqs)
+	if (irq_num >= min(kvm->arch.vgic.nr_irqs, 1020))
 		return -EINVAL;
 
 	vcpu_id = vgic_update_irq_pending(kvm, cpuid, irq_num, level);
@@ -2161,10 +2161,7 @@ int kvm_set_irq(struct kvm *kvm, int irq
 
 	BUG_ON(!vgic_initialized(kvm));
 
-	if (spi > kvm->arch.vgic.nr_irqs)
-		return -EINVAL;
 	return kvm_vgic_inject_irq(kvm, 0, spi, level);
-
 }
 
 /* MSI not implemented yet */


Patches currently in stable-queue which might be from marc.zyngier@arm.com are

queue-4.1/kvm-arm-arm64-vgic-avoid-injecting-reserved-irq-numbers.patch
queue-4.1/arm-kvm-psci-fix-handling-of-unimplemented-functions.patch
queue-4.1/arm-kvm-force-execution-of-hcptr-access-on-vm-exit.patch