diff options
| author | Mark Rutland <mark.rutland@arm.com> | 2018-04-25 17:13:42 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-06-21 04:02:49 +0900 |
| commit | 81d27c6ed637d5088901de01f0f5c7a624dad119 (patch) | |
| tree | 303a670d2a88be797598e806a53414d64330eaa3 /virt/kvm | |
| parent | e3d1002e14cede45fc543c82b469dd21c5ba027f (diff) | |
KVM: arm/arm64: vgic: fix possible spectre-v1 in vgic_mmio_read_apr()
[ Upstream commit 5e1ca5e23b167987d5b6d8b08f2d5b7dd2d13f49 ]
It's possible for userspace to control n. Sanitize n when using it as an
array index.
Note that while it appears that n must be bound to the interval [0,3]
due to the way it is extracted from addr, we cannot guarantee that
compiler transformations (and/or future refactoring) will ensure this is
the case, and given this is a slow path it's better to always perform
the masking.
Found by smatch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: kvmarm@lists.cs.columbia.edu
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'virt/kvm')
| -rw-r--r-- | virt/kvm/arm/vgic/vgic-mmio-v2.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/virt/kvm/arm/vgic/vgic-mmio-v2.c b/virt/kvm/arm/vgic/vgic-mmio-v2.c index b3d4a10f09a1..af003268bf3e 100644 --- a/virt/kvm/arm/vgic/vgic-mmio-v2.c +++ b/virt/kvm/arm/vgic/vgic-mmio-v2.c @@ -14,6 +14,8 @@ #include <linux/irqchip/arm-gic.h> #include <linux/kvm.h> #include <linux/kvm_host.h> +#include <linux/nospec.h> + #include <kvm/iodev.h> #include <kvm/arm_vgic.h> @@ -320,6 +322,9 @@ static unsigned long vgic_mmio_read_apr(struct kvm_vcpu *vcpu, if (n > vgic_v3_max_apr_idx(vcpu)) return 0; + + n = array_index_nospec(n, 4); + /* GICv3 only uses ICH_AP1Rn for memory mapped (GICv2) guests */ return vgicv3->vgic_ap1r[n]; } |