From: "Michael S. Tsirkin" <mst@xxxxxxxxxx> This patch has been added to the 4.1 stable tree. If you have any objections, please let us know. =============== [ Upstream commit 887349f69f37e71e2a8bfbd743831625a0b2ff51 ] Calling return copy_to_user(...) or return copy_from_user in an ioctl will not do the right thing if there's a pagefault: copy_to_user/copy_from_user return the number of bytes not copied in this case. Fix up kvm on mips to do return copy_to_user(...)) ? -EFAULT : 0; and return copy_from_user(...)) ? -EFAULT : 0; everywhere. Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx> Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx> Cc: James Hogan <james.hogan@xxxxxxxxxx> Cc: linux-kernel@xxxxxxxxxxxxxxx Cc: linux-mips@xxxxxxxxxxxxxx Cc: stable@xxxxxxxxxxxxxxx Cc: kvm@xxxxxxxxxxxxxxx Patchwork: https://patchwork.linux-mips.org/patch/12709/ Signed-off-by: Ralf Baechle <ralf@xxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sasha.levin@xxxxxxxxxx> --- arch/mips/kvm/mips.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c index 22ee0af..ace4ed7 100644 --- a/arch/mips/kvm/mips.c +++ b/arch/mips/kvm/mips.c @@ -700,7 +700,7 @@ static int kvm_mips_get_reg(struct kvm_vcpu *vcpu, } else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) { void __user *uaddr = (void __user *)(long)reg->addr; - return copy_to_user(uaddr, vs, 16); + return copy_to_user(uaddr, vs, 16) ? -EFAULT : 0; } else { return -EINVAL; } @@ -730,7 +730,7 @@ static int kvm_mips_set_reg(struct kvm_vcpu *vcpu, } else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) { void __user *uaddr = (void __user *)(long)reg->addr; - return copy_from_user(vs, uaddr, 16); + return copy_from_user(vs, uaddr, 16) ? -EFAULT : 0; } else { return -EINVAL; } -- 2.5.0
