Re: [PATCH v2] vfio: Fix memory leak of hostwin

From: Alex Williamson <alex.williamson@redhat.com>
To: Peng Liang <liangpeng10@huawei.com>
Cc: zhengchuan@huawei.com, wanghao232@huawei.com,
	qemu-devel@nongnu.org, xiexiangyou@huawei.com,
	qemu-stable@nongnu.org
Subject: Re: [PATCH v2] vfio: Fix memory leak of hostwin
Date: Wed, 17 Nov 2021 12:19:26 -0700	[thread overview]
Message-ID: <20211117121926.458aad95.alex.williamson@redhat.com> (raw)
In-Reply-To: <20211117014739.1839263-1-liangpeng10@huawei.com>

On Wed, 17 Nov 2021 09:47:39 +0800
Peng Liang <liangpeng10@huawei.com> wrote:

> hostwin is allocated and added to hostwin_list in vfio_host_win_add, but
> it is only deleted from hostwin_list in vfio_host_win_del, which causes
> a memory leak.  Also, freeing all elements in hostwin_list is missing in
> vfio_disconnect_container.
> 
> Fix: 2e4109de8e58 ("vfio/spapr: Create DMA window dynamically (SPAPR IOMMU v2)")
> CC: qemu-stable@nongnu.org
> Signed-off-by: Peng Liang <liangpeng10@huawei.com>
> ---
> v1 -> v2:
> - Don't change to _SAFE variant in vfio_host_win_del. [Alex]
> ---
>  hw/vfio/common.c | 8 ++++++++
>  1 file changed, 8 insertions(+)

Thanks, pull request sent to include this in 6.2.

Alex

> 
> diff --git a/hw/vfio/common.c b/hw/vfio/common.c
> index dd387b0d3959..080046e3f511 100644
> --- a/hw/vfio/common.c
> +++ b/hw/vfio/common.c
> @@ -551,6 +551,7 @@ static int vfio_host_win_del(VFIOContainer *container, hwaddr min_iova,
>      QLIST_FOREACH(hostwin, &container->hostwin_list, hostwin_next) {
>          if (hostwin->min_iova == min_iova && hostwin->max_iova == max_iova) {
>              QLIST_REMOVE(hostwin, hostwin_next);
> +            g_free(hostwin);
>              return 0;
>          }
>      }
> @@ -2239,6 +2240,7 @@ static void vfio_disconnect_container(VFIOGroup *group)
>      if (QLIST_EMPTY(&container->group_list)) {
>          VFIOAddressSpace *space = container->space;
>          VFIOGuestIOMMU *giommu, *tmp;
> +        VFIOHostDMAWindow *hostwin, *next;
>  
>          QLIST_REMOVE(container, next);
>  
> @@ -2249,6 +2251,12 @@ static void vfio_disconnect_container(VFIOGroup *group)
>              g_free(giommu);
>          }
>  
> +        QLIST_FOREACH_SAFE(hostwin, &container->hostwin_list, hostwin_next,
> +                           next) {
> +            QLIST_REMOVE(hostwin, hostwin_next);
> +            g_free(hostwin);
> +        }
> +
>          trace_vfio_disconnect_container(container->fd);
>          close(container->fd);
>          g_free(container);