From d920eaa482d63f92c8a00a710a04e6c0072bc8f6 Mon Sep 17 00:00:00 2001 From: Ian Jackson Date: Fri, 29 Apr 2016 17:18:44 +0100 Subject: [PATCH] libxl: Do not trust backend for vtpm in getinfo (except uuid) * Do not check the backend for existence. We have already read the /libxl path so know that the vtpm exists (or is supposed to); if the backend doesn't exist then that must be the backend's doing. * Get the frontend path from the /libxl directory. * The frontend domid is the guest domid, and does not need to be read from xenstore (!) We still attempt to read the uuid from the backend. This will be fixed in the next patch. This is part of XSA-178. Signed-off-by: Ian Jackson Reviewed-by: Wei Liu --- tools/libxl/libxl.c | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-) diff --git a/tools/libxl/libxl.c b/tools/libxl/libxl.c index b440099423..6f96514aec 100644 --- a/tools/libxl/libxl.c +++ b/tools/libxl/libxl.c @@ -1925,9 +1925,6 @@ int libxl_device_vtpm_getinfo(libxl_ctx *ctx, if (!vtpminfo->backend) { goto err; } - if(!libxl__xs_read(gc, XBT_NULL, vtpminfo->backend)) { - goto err; - } rc = libxl__backendpath_parse_domid(gc, vtpminfo->backend, &vtpminfo->backend_id); @@ -1946,11 +1943,8 @@ int libxl_device_vtpm_getinfo(libxl_ctx *ctx, vtpminfo->rref = val ? strtoul(val, NULL, 10) : -1; vtpminfo->frontend = xs_read(ctx->xsh, XBT_NULL, - GCSPRINTF("%s/frontend", vtpminfo->backend), NULL); - - val = libxl__xs_read(gc, XBT_NULL, - GCSPRINTF("%s/frontend-id", vtpminfo->backend)); - vtpminfo->frontend_id = val ? strtoul(val, NULL, 10) : -1; + GCSPRINTF("%s/frontend", libxl_path), NULL); + vtpminfo->frontend_id = domid; val = libxl__xs_read(gc, XBT_NULL, GCSPRINTF("%s/uuid", vtpminfo->backend));