Skip to content
Permalink
Browse files

xen: restrict: use xentoolcore_restrict_all

And insist that it works.

Drop individual use of xendevicemodel_restrict and
xenforeignmemory_restrict.  These are not actually effective in this
version of qemu, because qemu has a large number of fds open onto
various Xen control devices.

The restriction arrangements are still not right, because the
restriction needs to be done very late - after qemu has opened all of
its control fds.

xentoolcore_restrict_all and xentoolcore.h are available in Xen 4.10
and later, only.  Provide a compatibility stub.  And drop the
compatibility stubs for the old functions.

Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
  • Loading branch information...
ijackson-citrix committed Sep 15, 2017
1 parent 58ea9a7 commit 0ef4d87da58dfe0e0e466414701c103b7a44df65
Showing with 11 additions and 35 deletions.
  1. +11 −35 include/hw/xen/xen_common.h
@@ -91,6 +91,16 @@ static inline void *xenforeignmemory_map2(xenforeignmemory_handle *h,
return xenforeignmemory_map(h, dom, prot, pages, arr, err);
}

static inline int xentoolcore_restrict_all(domid_t domid)
{
errno = ENOTTY;
return -1;
}

#else /* CONFIG_XEN_CTRL_INTERFACE_VERSION >= 41000 */

#include <xentoolcore.h>

#endif

#if CONFIG_XEN_CTRL_INTERFACE_VERSION < 40900
@@ -218,20 +228,6 @@ static inline int xendevicemodel_set_mem_type(
return xc_hvm_set_mem_type(dmod, domid, mem_type, first_pfn, nr);
}

static inline int xendevicemodel_restrict(
xendevicemodel_handle *dmod, domid_t domid)
{
errno = ENOTTY;
return -1;
}

static inline int xenforeignmemory_restrict(
xenforeignmemory_handle *fmem, domid_t domid)
{
errno = ENOTTY;
return -1;
}

#else /* CONFIG_XEN_CTRL_INTERFACE_VERSION >= 40900 */

#undef XC_WANT_COMPAT_DEVICEMODEL_API
@@ -290,28 +286,8 @@ static inline int xen_modified_memory(domid_t domid, uint64_t first_pfn,
static inline int xen_restrict(domid_t domid)
{
int rc;

/* Attempt to restrict devicemodel operations */
rc = xendevicemodel_restrict(xen_dmod, domid);
rc = xentoolcore_restrict_all(domid);
trace_xen_domid_restrict(rc ? errno : 0);

if (rc < 0) {
/*
* If errno is ENOTTY then restriction is not implemented so
* there's no point in trying to restrict other types of
* operation, but it should not be treated as a failure.
*/
if (errno == ENOTTY) {
return 0;
}

return rc;
}

/* Restrict foreignmemory operations */
rc = xenforeignmemory_restrict(xen_fmem, domid);
trace_xen_domid_restrict(rc ? errno : 0);

return rc;
}

0 comments on commit 0ef4d87

Please sign in to comment.
You can’t perform that action at this time.