[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH] vnc: clear vs->tlscreds after unparenting it
From: |
Daniel P. Berrange |
Subject: |
Re: [Qemu-devel] [PATCH] vnc: clear vs->tlscreds after unparenting it |
Date: |
Tue, 12 Jan 2016 13:01:19 +0000 |
User-agent: |
Mutt/1.5.24 (2015-08-30) |
On Tue, Jan 12, 2016 at 01:52:39PM +0100, Wolfgang Bumiller wrote:
> This pointer should be cleared in vnc_display_close()
> otherwise a use-after-free can happen when when using the
> old style 'x509' and 'tls' options rather than a persistent
> tls-creds -object, by issuing monitor commands to change
> the vnc server like so:
>
> Start with: -vnc unix:test.socket,x509,tls
> Then use the following monitor command:
> change vnc unix:test.socket
>
> After this the pointer is still set but invalid and a crash
> can be triggered for instance by issuing the same command a
> second time which will try to object_unparent() the same
> pointer again.
> ---
> ui/vnc.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/ui/vnc.c b/ui/vnc.c
> index 09756cd..35843b5 100644
> --- a/ui/vnc.c
> +++ b/ui/vnc.c
> @@ -3134,6 +3134,7 @@ static void vnc_display_close(VncDisplay *vs)
> vs->subauth = VNC_AUTH_INVALID;
> if (vs->tlscreds) {
> object_unparent(OBJECT(vs->tlscreds));
> + vs->tlscreds = NULL;
> }
> g_free(vs->tlsaclname);
> vs->tlsaclname = NULL;
Reviewed-by: Daniel P. Berrange <address@hidden>
Regards,
Daniel
--
|: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :|
|: http://libvirt.org -o- http://virt-manager.org :|
|: http://autobuild.org -o- http://search.cpan.org/~danberr/ :|
|: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|