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Subject: Re: [PATCH] vhost-vdpa: fix memory leak in error path
To:     Li Qiang <liq3ea@163.com>, mst@redhat.com
Cc:     kvm@vger.kernel.org, virtualization@lists.linux-foundation.org,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        liq3ea@gmail.com
References: <20200909154120.363209-1-liq3ea@163.com>
From:   Jason Wang <jasowang@redhat.com>
Message-ID: <bfae5c35-355a-8d8a-5057-a970db24ee41@redhat.com>
Date:   Thu, 10 Sep 2020 09:56:05 +0800
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On 2020/9/9 下午11:41, Li Qiang wrote:
> Free the 'page_list' when the 'npages' is zero.
>
> Signed-off-by: Li Qiang <liq3ea@163.com>
> ---
>   drivers/vhost/vdpa.c | 8 ++++++--
>   1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
> index 3fab94f88894..6a9fcaf1831d 100644
> --- a/drivers/vhost/vdpa.c
> +++ b/drivers/vhost/vdpa.c
> @@ -609,8 +609,10 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,
>   		gup_flags |= FOLL_WRITE;
>   
>   	npages = PAGE_ALIGN(msg->size + (iova & ~PAGE_MASK)) >> PAGE_SHIFT;
> -	if (!npages)
> -		return -EINVAL;
> +	if (!npages) {
> +		ret = -EINVAL;
> +		goto free_page;
> +	}
>   
>   	mmap_read_lock(dev->mm);
>   
> @@ -666,6 +668,8 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,
>   		atomic64_sub(npages, &dev->mm->pinned_vm);
>   	}
>   	mmap_read_unlock(dev->mm);
> +
> +free_page:
>   	free_page((unsigned long)page_list);
>   	return ret;
>   }


Cc: stable@vger.kernel.org

Acked-by: Jason Wang <jasowang@redhat.com>