[PATCH for-4.5] arm/kvm: fix ioctl error handling
From: mst@redhat.com (Michael S. Tsirkin)
Date: 2016-02-28 15:32:15
Also in:
kvm, kvmarm, lkml, stable
Subsystem:
arm port, arm64 port (aarch64 architecture), kernel virtual machine for arm64 (kvm/arm64), the rest · Maintainers:
Russell King, Catalin Marinas, Will Deacon, Marc Zyngier, Oliver Upton, Linus Torvalds
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. Cc: stable at vger.kernel.org Signed-off-by: Michael S. Tsirkin <mst@redhat.com> --- Compiled only. arch/arm/kvm/guest.c | 2 +- arch/arm64/kvm/guest.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/arm/kvm/guest.c b/arch/arm/kvm/guest.c
index 5fa69d7..99361f1 100644
--- a/arch/arm/kvm/guest.c
+++ b/arch/arm/kvm/guest.c@@ -161,7 +161,7 @@ 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)
diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c
index fcb7788..9e54ad7 100644
--- a/arch/arm64/kvm/guest.c
+++ b/arch/arm64/kvm/guest.c@@ -194,7 +194,7 @@ 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; } /**
--
MST