| Message ID | 20210412150034.29185-1-eric.auger@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: arm/arm64: Fix KVM_VGIC_V3_ADDR_TYPE_REDIST read | expand |
On 2021/4/12 23:00, Eric Auger wrote: > When reading the base address of the a REDIST region > through KVM_VGIC_V3_ADDR_TYPE_REDIST we expect the > redistributor region list to be populated with a single > element. > > However list_first_entry() expects the list to be non empty. Indeed, list_first_entry() always return a non-null ptr. If the list is empty, it will mistake the list head as the first element. > Instead we should use list_first_entry_or_null which effectively > returns NULL if the list is empty. > > Fixes: dbd9733ab674 ("KVM: arm/arm64: Replace the single rdist region by a list") > Cc: <Stable@vger.kernel.org> # v4.18+ > Signed-off-by: Eric Auger <eric.auger@redhat.com> > Reported-by: Gavin Shan <gshan@redhat.com> > --- > arch/arm64/kvm/vgic/vgic-kvm-device.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/kvm/vgic/vgic-kvm-device.c b/arch/arm64/kvm/vgic/vgic-kvm-device.c > index 44419679f91a..5eaede3e3b5a 100644 > --- a/arch/arm64/kvm/vgic/vgic-kvm-device.c > +++ b/arch/arm64/kvm/vgic/vgic-kvm-device.c > @@ -87,8 +87,8 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write) > r = vgic_v3_set_redist_base(kvm, 0, *addr, 0); > goto out; > } > - rdreg = list_first_entry(&vgic->rd_regions, > - struct vgic_redist_region, list); > + rdreg = list_first_entry_or_null(&vgic->rd_regions, > + struct vgic_redist_region, list); > if (!rdreg) > addr_ptr = &undef_value; > else >
On Mon, 12 Apr 2021 17:00:34 +0200, Eric Auger wrote: > When reading the base address of the a REDIST region > through KVM_VGIC_V3_ADDR_TYPE_REDIST we expect the > redistributor region list to be populated with a single > element. > > However list_first_entry() expects the list to be non empty. > Instead we should use list_first_entry_or_null which effectively > returns NULL if the list is empty. Applied to kvm-arm64/vgic-5.13, thanks! [1/1] KVM: arm/arm64: Fix KVM_VGIC_V3_ADDR_TYPE_REDIST read commit: 94ac0835391efc1a30feda6fc908913ec012951e Cheers, M.
diff --git a/arch/arm64/kvm/vgic/vgic-kvm-device.c b/arch/arm64/kvm/vgic/vgic-kvm-device.c index 44419679f91a..5eaede3e3b5a 100644 --- a/arch/arm64/kvm/vgic/vgic-kvm-device.c +++ b/arch/arm64/kvm/vgic/vgic-kvm-device.c @@ -87,8 +87,8 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write) r = vgic_v3_set_redist_base(kvm, 0, *addr, 0); goto out; } - rdreg = list_first_entry(&vgic->rd_regions, - struct vgic_redist_region, list); + rdreg = list_first_entry_or_null(&vgic->rd_regions, + struct vgic_redist_region, list); if (!rdreg) addr_ptr = &undef_value; else
When reading the base address of the a REDIST region through KVM_VGIC_V3_ADDR_TYPE_REDIST we expect the redistributor region list to be populated with a single element. However list_first_entry() expects the list to be non empty. Instead we should use list_first_entry_or_null which effectively returns NULL if the list is empty. Fixes: dbd9733ab674 ("KVM: arm/arm64: Replace the single rdist region by a list") Cc: <Stable@vger.kernel.org> # v4.18+ Signed-off-by: Eric Auger <eric.auger@redhat.com> Reported-by: Gavin Shan <gshan@redhat.com> --- arch/arm64/kvm/vgic/vgic-kvm-device.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)