Re: [PATCH] riscv/kvm: fix guest vector leak on host alloc failure

From: Anup Patel

Date: Sat Mar 28 2026 - 06:07:03 EST


On Sat, Mar 28, 2026 at 2:52 PM Yufan Chen <yufan.chen@xxxxxxxxx> wrote:
>
> From: Yufan Chen <ericterminal@xxxxxxxxx>
>
> When allocating vector context for a vCPU, guest_context.vector.datap is allocated before host_context.vector.datap. If the second allocation fails, the function returns -ENOMEM directly and leaks the guest buffer.
>
> Switch the failure path to centralized cleanup. On host allocation failure, free guest_context.vector.datap, clear the pointer, and return -ENOMEM through a shared exit label.
>
> Signed-off-by: Yufan Chen <ericterminal@xxxxxxxxx>

This is already fixed by patch "riscv: kvm: fix vector context allocation leak".

Regards,
Anup

> ---
> arch/riscv/kvm/vcpu_vector.c | 12 ++++++++++--
> 1 file changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/arch/riscv/kvm/vcpu_vector.c b/arch/riscv/kvm/vcpu_vector.c
> index 05f3cc2d8..4c2f92dce 100644
> --- a/arch/riscv/kvm/vcpu_vector.c
> +++ b/arch/riscv/kvm/vcpu_vector.c
> @@ -75,15 +75,23 @@ void kvm_riscv_vcpu_host_vector_restore(struct kvm_cpu_context *cntx)
>
> int kvm_riscv_vcpu_alloc_vector_context(struct kvm_vcpu *vcpu)
> {
> + int rc = -ENOMEM;
> +
> vcpu->arch.guest_context.vector.datap = kzalloc(riscv_v_vsize, GFP_KERNEL);
> if (!vcpu->arch.guest_context.vector.datap)
> - return -ENOMEM;
> + goto out;
>
> vcpu->arch.host_context.vector.datap = kzalloc(riscv_v_vsize, GFP_KERNEL);
> if (!vcpu->arch.host_context.vector.datap)
> - return -ENOMEM;
> + goto free_guest_vector_datap;
>
> return 0;
> +
> +free_guest_vector_datap:
> + kfree(vcpu->arch.guest_context.vector.datap);
> + vcpu->arch.guest_context.vector.datap = NULL;
> +out:
> + return rc;
> }
>
> void kvm_riscv_vcpu_free_vector_context(struct kvm_vcpu *vcpu)
> --
> 2.47.3
>