| From 6906cdef6d72b58c7850b14d5dc45eaaf0b4f41c Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Fri, 16 Jul 2021 12:43:10 +1000 |
| Subject: KVM: PPC: Fix kvm_arch_vcpu_ioctl vcpu_load leak |
| |
| From: Nicholas Piggin <npiggin@gmail.com> |
| |
| [ Upstream commit bc4188a2f56e821ea057aca6bf444e138d06c252 ] |
| |
| vcpu_put is not called if the user copy fails. This can result in preempt |
| notifier corruption and crashes, among other issues. |
| |
| Fixes: b3cebfe8c1ca ("KVM: PPC: Move vcpu_load/vcpu_put down to each ioctl case in kvm_arch_vcpu_ioctl") |
| Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru> |
| Signed-off-by: Nicholas Piggin <npiggin@gmail.com> |
| Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> |
| Link: https://lore.kernel.org/r/20210716024310.164448-2-npiggin@gmail.com |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| arch/powerpc/kvm/powerpc.c | 4 ++-- |
| 1 file changed, 2 insertions(+), 2 deletions(-) |
| |
| diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c |
| index a2a68a958fa0..6e4f03c02a0a 100644 |
| --- a/arch/powerpc/kvm/powerpc.c |
| +++ b/arch/powerpc/kvm/powerpc.c |
| @@ -2045,9 +2045,9 @@ long kvm_arch_vcpu_ioctl(struct file *filp, |
| { |
| struct kvm_enable_cap cap; |
| r = -EFAULT; |
| - vcpu_load(vcpu); |
| if (copy_from_user(&cap, argp, sizeof(cap))) |
| goto out; |
| + vcpu_load(vcpu); |
| r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap); |
| vcpu_put(vcpu); |
| break; |
| @@ -2071,9 +2071,9 @@ long kvm_arch_vcpu_ioctl(struct file *filp, |
| case KVM_DIRTY_TLB: { |
| struct kvm_dirty_tlb dirty; |
| r = -EFAULT; |
| - vcpu_load(vcpu); |
| if (copy_from_user(&dirty, argp, sizeof(dirty))) |
| goto out; |
| + vcpu_load(vcpu); |
| r = kvm_vcpu_ioctl_dirty_tlb(vcpu, &dirty); |
| vcpu_put(vcpu); |
| break; |
| -- |
| 2.30.2 |
| |
