Re: [Qemu-devel] [PATCH V2] net: tap: fix NULL dereference when passing invalid parameters to tap

[Stefan Hajnoczi <stefanha@gmail.com>]

On Tue, Jun 04, 2013 at 01:18:17PM +0800, Jason Wang wrote:
> This patch forbid the following invalid parameters to tap:
> 
> 1) fd and vhostfds were specified but vhostfd were not specified
> 2) vhostfds were specified but fds were not specified
> 3) fds and vhostfd were specified
> 
> For 1 and 2, net_init_tap_one() will still pass NULL as vhostfdname to
> monitor_handle_fd_param(), which may crash the qemu.
> 
> Also remove the unnecessary has_fd check.
> 
> Cc: Paolo Bonzini <pbonzini@redhat.com>
> Cc: Stefan Hajnoczi <shajnocz@redhat.com>
> Cc: Laszlo Ersek <lersek@redhat.com>
> Cc: qemu-stable@nongnu.org
> Signed-off-by: Jason Wang <jasowang@redhat.com>
> 
> ---
> Changes from v1:
> - check vhostfds for has_helper and all other cases
> - remove the unnecessary check for has_fd when fds were specified
> ---
>  net/tap.c |   18 ++++++++++++------
>  1 files changed, 12 insertions(+), 6 deletions(-)

Thanks, applied to my net tree:
https://github.com/stefanha/qemu/commits/net

Stefan