3.16.7-ckt26 -stable review patch. If anyone has any objections, please let me know.
---8<------------------------------------------------------------ From: "Michael S. Tsirkin" <[email protected]> commit 4cad67fca3fc952d6f2ed9e799621f07666a560f upstream. Calling return copy_to_user(...) in an ioctl will not do the right thing if there's a pagefault: copy_to_user returns the number of bytes not copied in this case. Fix up kvm to do return copy_to_user(...)) ? -EFAULT : 0; everywhere. Acked-by: Christoffer Dall <[email protected]> Signed-off-by: Michael S. Tsirkin <[email protected]> Signed-off-by: Marc Zyngier <[email protected]> [ luis: backported to 3.16: - dropped changes to arch/arm64/kvm/guest.c ] Signed-off-by: Luis Henriques <[email protected]> --- arch/arm/kvm/guest.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm/kvm/guest.c b/arch/arm/kvm/guest.c index 2786eae10c0d..f3f6415b7828 100644 --- a/arch/arm/kvm/guest.c +++ b/arch/arm/kvm/guest.c @@ -183,7 +183,7 @@ static int get_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) u64 val; val = kvm_arm_timer_get_reg(vcpu, reg->id); - return copy_to_user(uaddr, &val, KVM_REG_SIZE(reg->id)); + return copy_to_user(uaddr, &val, KVM_REG_SIZE(reg->id)) ? -EFAULT : 0; } static unsigned long num_core_regs(void)
