[v2] riscv: kvm: fix vector context allocation leak

[PATCH v2] riscv: kvm: fix vector context allocation leak

Posted by Osama Abdelkader 3 weeks ago

When the second kzalloc (host_context.vector.datap) fails in
kvm_riscv_vcpu_alloc_vector_context, the first allocation
(guest_context.vector.datap) is leaked. Free it before returning.

Fixes: 0f4b82579716 ("riscv: KVM: Add vector lazy save/restore support")
Cc: stable@vger.kernel.org
Signed-off-by: Osama Abdelkader <osama.abdelkader@gmail.com>
---
v2:
- Add Fixes: tag
- Add Cc: stable@vger.kernel.org
---
 arch/riscv/kvm/vcpu_vector.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/riscv/kvm/vcpu_vector.c b/arch/riscv/kvm/vcpu_vector.c
index 05f3cc2d8e31..5b6ad82d47be 100644
--- a/arch/riscv/kvm/vcpu_vector.c
+++ b/arch/riscv/kvm/vcpu_vector.c
@@ -80,8 +80,11 @@ int kvm_riscv_vcpu_alloc_vector_context(struct kvm_vcpu *vcpu)
 		return -ENOMEM;
 
 	vcpu->arch.host_context.vector.datap = kzalloc(riscv_v_vsize, GFP_KERNEL);
-	if (!vcpu->arch.host_context.vector.datap)
+	if (!vcpu->arch.host_context.vector.datap) {
+		kfree(vcpu->arch.guest_context.vector.datap);
+		vcpu->arch.guest_context.vector.datap = NULL;
 		return -ENOMEM;
+	}
 
 	return 0;
 }
-- 
2.43.0

Re: [PATCH v2] riscv: kvm: fix vector context allocation leak

Posted by Anup Patel 1 week, 3 days ago

On Mon, Mar 16, 2026 at 8:46 PM Osama Abdelkader
<osama.abdelkader@gmail.com> wrote:
>
> When the second kzalloc (host_context.vector.datap) fails in
> kvm_riscv_vcpu_alloc_vector_context, the first allocation
> (guest_context.vector.datap) is leaked. Free it before returning.
>
> Fixes: 0f4b82579716 ("riscv: KVM: Add vector lazy save/restore support")
> Cc: stable@vger.kernel.org
> Signed-off-by: Osama Abdelkader <osama.abdelkader@gmail.com>

Queued this patch for Linux-7.1

Thanks,
Anup

> ---
> v2:
> - Add Fixes: tag
> - Add Cc: stable@vger.kernel.org
> ---
>  arch/riscv/kvm/vcpu_vector.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/arch/riscv/kvm/vcpu_vector.c b/arch/riscv/kvm/vcpu_vector.c
> index 05f3cc2d8e31..5b6ad82d47be 100644
> --- a/arch/riscv/kvm/vcpu_vector.c
> +++ b/arch/riscv/kvm/vcpu_vector.c
> @@ -80,8 +80,11 @@ int kvm_riscv_vcpu_alloc_vector_context(struct kvm_vcpu *vcpu)
>                 return -ENOMEM;
>
>         vcpu->arch.host_context.vector.datap = kzalloc(riscv_v_vsize, GFP_KERNEL);
> -       if (!vcpu->arch.host_context.vector.datap)
> +       if (!vcpu->arch.host_context.vector.datap) {
> +               kfree(vcpu->arch.guest_context.vector.datap);
> +               vcpu->arch.guest_context.vector.datap = NULL;
>                 return -ENOMEM;
> +       }
>
>         return 0;
>  }
> --
> 2.43.0
>

Re: [PATCH v2] riscv: kvm: fix vector context allocation leak

Posted by Andy Chiu 3 weeks ago

Hi Osama,

Thanks for spotting this,

On Mon, Mar 16, 2026 at 10:16 AM Osama Abdelkader
<osama.abdelkader@gmail.com> wrote:
>
> When the second kzalloc (host_context.vector.datap) fails in
> kvm_riscv_vcpu_alloc_vector_context, the first allocation
> (guest_context.vector.datap) is leaked. Free it before returning.
>
> Fixes: 0f4b82579716 ("riscv: KVM: Add vector lazy save/restore support")
> Cc: stable@vger.kernel.org
> Signed-off-by: Osama Abdelkader <osama.abdelkader@gmail.com>

Reviewed-by: Andy Chiu <andybnac@gmail.com>

> ---
> v2:
> - Add Fixes: tag
> - Add Cc: stable@vger.kernel.org
> ---
>  arch/riscv/kvm/vcpu_vector.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/arch/riscv/kvm/vcpu_vector.c b/arch/riscv/kvm/vcpu_vector.c
> index 05f3cc2d8e31..5b6ad82d47be 100644
> --- a/arch/riscv/kvm/vcpu_vector.c
> +++ b/arch/riscv/kvm/vcpu_vector.c
> @@ -80,8 +80,11 @@ int kvm_riscv_vcpu_alloc_vector_context(struct kvm_vcpu *vcpu)
>                 return -ENOMEM;
>
>         vcpu->arch.host_context.vector.datap = kzalloc(riscv_v_vsize, GFP_KERNEL);
> -       if (!vcpu->arch.host_context.vector.datap)
> +       if (!vcpu->arch.host_context.vector.datap) {
> +               kfree(vcpu->arch.guest_context.vector.datap);
> +               vcpu->arch.guest_context.vector.datap = NULL;
>                 return -ENOMEM;
> +       }
>
>         return 0;
>  }
> --
> 2.43.0
>