Re: [Qemu-devel] [PATCH] migration/rdma: Fix qemu_rdma_cleanup null check

[Peter Xu <peterx@redhat.com>]

On Thu, Feb 14, 2019 at 06:53:51PM +0000, Dr. David Alan Gilbert (git) wrote:
> From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
> 
> If the migration fails before the channel is open (e.g. a bad
> address) we end up in the cleanup with rdma->channel==NULL.
> 
> Spotted by Coverity: CID 1398634
> Fixes: fbbaacab2758cb3f32a0
> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
> ---
>  migration/rdma.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/migration/rdma.c b/migration/rdma.c
> index 54a3c11540..9fa3b176eb 100644
> --- a/migration/rdma.c
> +++ b/migration/rdma.c
> @@ -2321,7 +2321,9 @@ static void qemu_rdma_cleanup(RDMAContext *rdma)
>          rdma->connected = false;
>      }
>  
> -    qemu_set_fd_handler(rdma->channel->fd, NULL, NULL, NULL);
> +    if (rdma->channel) {
> +        qemu_set_fd_handler(rdma->channel->fd, NULL, NULL, NULL);
> +    }

IIUC there's no strict ordering constraint on resetting the fd
handler, then how about simply moving this line into the below "if
(rdma->channel)" altogether?

Regards,

-- 
Peter Xu