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[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [Xen-devel] [PATCH v4 04/34] HYPERCALL_version_op. New hypercall mirroring XENVER_ but sane.
On Tue, Mar 22, 2016 at 07:28:57PM +0000, Andrew Cooper wrote:
> On 22/03/16 18:57, Konrad Rzeszutek Wilk wrote:
> >>>>> --- a/xen/include/xsm/dummy.h
> >>>>> +++ b/xen/include/xsm/dummy.h
> >>>>> @@ -751,3 +751,22 @@ static XSM_INLINE int xsm_xen_version
> >>>>> (XSM_DEFAULT_ARG uint32_t op)
> >>>>> return xsm_default_action(XSM_PRIV, current->domain, NULL);
> >>>>> }
> >>>>> }
> >>>>> +
> >>>>> +static XSM_INLINE int xsm_version_op (XSM_DEFAULT_ARG uint32_t op)
> >>>>> +{
> >>>>> + XSM_ASSERT_ACTION(XSM_OTHER);
> >>>>> + switch ( op )
> >>>>> + {
> >>>>> + case XEN_VERSION_version:
> >>>>> + case XEN_VERSION_extraversion:
> >>>>> + case XEN_VERSION_capabilities:
> >>>>> + case XEN_VERSION_platform_parameters:
> >>>>> + case XEN_VERSION_get_features:
> >>>>> + case XEN_VERSION_pagesize:
> >>>>> + case XEN_VERSION_guest_handle:
> >>>>> + /* These MUST always be accessible to any guest by default. */
> >>>>> + return xsm_default_action(XSM_HOOK, current->domain, NULL);
> >>>>> + default:
> >>>>> + return xsm_default_action(XSM_PRIV, current->domain, NULL);
> >>>> Considering that we seem to have settled on some exceptions here
> >>>> for the change adding XSM check to the legacy version op, do you
> >>>> really think going with no exception at all here is the right approach?
> >>>> Because if we do, that'll prevent guests getting fully converted over
> >>>> to the new interface. Of course, we could also make this conversion
> >>>> specifically a non-goal, and omit e.g. XEN_VERSION_VERSION from
> >>>> this new interface.
> >>> No no. I think convesion is the right long-term goal.
> >>>
> >>> However the nice thing about this hypercall is that it can return -EPERM.
> >>>
> >>> Making it always return an value for XEN_VERSION_version,
> >>> XEN_VERSION_platform_parameters, XEN_VERSION_get_features means that
> >>> there are some exceptions to this "can return -EPERM" as they will
> >>> be guaranteed an postive return value. They can ignore the -EPERM
> >>> case.
> >>>
> >>> And means that guest can still take shortcuts.
> >>>
> >>> I agree with you that guests need these hypercalls but at the same
> >>> time I am not sure what can be done so they don't fall flat on their
> >>> faces if they are presented with -EPERM. The Linux xenbus_init can be
> >>> modified to deal with this returning -EPERM where it makes some
> >>> assumptions.
> >>>
> >>> But in a likelyhood it is the bad assumption!
> >> I'm afraid I can't conclude what you mean to say with all of the
> >> above.
> > That I am waffling.
> >
> > Andrew, what is your opinion?
>
> Nothing good can come from failing a XEN_VERSION_version hypercall.
> There are a number easy ways for a guest to infer such information.
>
> XEN_VERSION_platform_parameters is only useful for 32bit PV guests, and
> the toolstack. Given that it is returning a fixed number in the ABI,
> nothing good can come of failing this either.
>
> get_features can effectively be failed for permission reasons by
> returning 0. As such, explicitly failing with -EPERM is similarly
> pointless.
Allright. So here it is:
From 0f82c5f4cd1537ab8555f2b94bb3fe738df69733 Mon Sep 17 00:00:00 2001
From: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
Date: Tue, 22 Mar 2016 12:03:21 -0400
Subject: [PATCH] HYPERCALL_version_op. New hypercall mirroring XENVER_ but
sane.
This hypercall mirrors the XENVER_ in that it has similar functionality.
However it is designed differently:
- No compat layer. The data structures are the same size on 32
as on 64-bit.
- The hypercall accepts three arguments - the command, pointer to
an buffer, and the length of the buffer.
- Each sub-ops can be "probed" for size by returning the size of
buffer that will be needed - if the buffer is NULL.
- Subops can complete even if the buffer is too small - truncated
data will be filled and hypercall will return -ENOBUFS.
- VERSION_commandline, VERSION_changeset are privileged.
- There is no XENVER_compile_info equivalent.
- The hypercall can return -EPERM and toolstack/OSes are expected
to deal with. However there are three subops: XEN_VERSION_version,
XEN_VERSION_platform_parameters and XEN_VERSION_get_features
that will always return an value as guests cannot survive without them.
While we combine some of the common code between XENVER_ and VERSION_
take the liberty of moving pae_extended_cr3 in x86 area.
Suggested-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
Acked-by: Daniel De Graaf <dgdegra@xxxxxxxxxxxxx> [XSM bits]
---
Cc: Daniel De Graaf <dgdegra@xxxxxxxxxxxxx>
Cc: Ian Jackson <ian.jackson@xxxxxxxxxxxxx>
Cc: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>
Cc: Wei Liu <wei.liu2@xxxxxxxxxx>
Cc: Stefano Stabellini <stefano.stabellini@xxxxxxxxxx>
Cc: Julien Grall <julien.grall@xxxxxxx>
Cc: Keir Fraser <keir@xxxxxxx>
Cc: Jan Beulich <jbeulich@xxxxxxxx>
Cc: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
v1-v3: Was not part of the series.
v4: New posting.
v5: Remove memset and use {}. Tweak copy_to_guest and capabilities_info,
add ASSERT(sz) per Andrew's review. Add cached=1 back in.
Per Jan, s/VERSION_OP/VERSION/, squash size check with do_version_op,
update the comments. Dropped Andrew's Review-by. Ate newlines.
Added initcall to guard against garbage being set in cached data.
---
---
tools/flask/policy/policy/modules/xen/xen.te | 7 +-
xen/arch/arm/traps.c | 1 +
xen/arch/x86/hvm/hvm.c | 1 +
xen/arch/x86/x86_64/compat/entry.S | 2 +
xen/arch/x86/x86_64/entry.S | 2 +
xen/common/compat/kernel.c | 2 +
xen/common/kernel.c | 228 ++++++++++++++++++++++-----
xen/include/public/arch-arm.h | 2 +
xen/include/public/version.h | 70 +++++++-
xen/include/public/xen.h | 1 +
xen/include/xen/hypercall.h | 4 +
xen/include/xsm/dummy.h | 21 +++
xen/include/xsm/xsm.h | 6 +
xen/xsm/dummy.c | 1 +
xen/xsm/flask/hooks.c | 35 ++++
xen/xsm/flask/policy/access_vectors | 21 ++-
16 files changed, 361 insertions(+), 43 deletions(-)
diff --git a/tools/flask/policy/policy/modules/xen/xen.te
b/tools/flask/policy/policy/modules/xen/xen.te
index 18f49b5..b528797 100644
--- a/tools/flask/policy/policy/modules/xen/xen.te
+++ b/tools/flask/policy/policy/modules/xen/xen.te
@@ -74,11 +74,12 @@ allow dom0_t xen_t:xen2 {
get_symbol
};
-# Allow dom0 to use all XENVER_ subops that have checks.
+# Allow dom0 to use all XENVER_ subops and VERSION subops that have checks.
# Note that dom0 is part of domain_type so this has duplicates.
allow dom0_t xen_t:version {
xen_extraversion xen_compile_info xen_capabilities
xen_changeset xen_pagesize xen_guest_handle xen_commandline
+ extraversion capabilities changeset pagesize guest_handle commandline
};
allow dom0_t xen_t:mmu memorymap;
@@ -145,10 +146,12 @@ if (guest_writeconsole) {
# pmu_ctrl is for)
allow domain_type xen_t:xen2 pmu_use;
-# For normal guests all possible except XENVER_commandline.
+# For normal guests all possible except XENVER_commandline, VERSION_changeset,
+# and VERSION_commandline
allow domain_type xen_t:version {
xen_extraversion xen_compile_info xen_capabilities
xen_changeset xen_pagesize xen_guest_handle
+ extraversion capabilities pagesize guest_handle
};
###############################################################################
diff --git a/xen/arch/arm/traps.c b/xen/arch/arm/traps.c
index 83744e8..31d2115 100644
--- a/xen/arch/arm/traps.c
+++ b/xen/arch/arm/traps.c
@@ -1235,6 +1235,7 @@ static arm_hypercall_t arm_hypercall_table[] = {
HYPERCALL(multicall, 2),
HYPERCALL(platform_op, 1),
HYPERCALL_ARM(vcpu_op, 3),
+ HYPERCALL(version_op, 3),
};
#ifndef NDEBUG
diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c
index 80d59ff..f16b590 100644
--- a/xen/arch/x86/hvm/hvm.c
+++ b/xen/arch/x86/hvm/hvm.c
@@ -5322,6 +5322,7 @@ static const struct {
COMPAT_CALL(platform_op),
COMPAT_CALL(mmuext_op),
HYPERCALL(xenpmu_op),
+ HYPERCALL(version_op),
HYPERCALL(arch_1)
};
diff --git a/xen/arch/x86/x86_64/compat/entry.S
b/xen/arch/x86/x86_64/compat/entry.S
index 33e2c12..fd25e84 100644
--- a/xen/arch/x86/x86_64/compat/entry.S
+++ b/xen/arch/x86/x86_64/compat/entry.S
@@ -394,6 +394,7 @@ ENTRY(compat_hypercall_table)
.quad do_tmem_op
.quad do_ni_hypercall /* reserved for XenClient */
.quad do_xenpmu_op /* 40 */
+ .quad do_version_op
.rept __HYPERVISOR_arch_0-((.-compat_hypercall_table)/8)
.quad compat_ni_hypercall
.endr
@@ -445,6 +446,7 @@ ENTRY(compat_hypercall_args_table)
.byte 1 /* do_tmem_op */
.byte 0 /* reserved for XenClient */
.byte 2 /* do_xenpmu_op */ /* 40 */
+ .byte 3 /* do_version_op */
.rept __HYPERVISOR_arch_0-(.-compat_hypercall_args_table)
.byte 0 /* compat_ni_hypercall */
.endr
diff --git a/xen/arch/x86/x86_64/entry.S b/xen/arch/x86/x86_64/entry.S
index 07ef096..b0e7257 100644
--- a/xen/arch/x86/x86_64/entry.S
+++ b/xen/arch/x86/x86_64/entry.S
@@ -730,6 +730,7 @@ ENTRY(hypercall_table)
.quad do_tmem_op
.quad do_ni_hypercall /* reserved for XenClient */
.quad do_xenpmu_op /* 40 */
+ .quad do_version_op
.rept __HYPERVISOR_arch_0-((.-hypercall_table)/8)
.quad do_ni_hypercall
.endr
@@ -781,6 +782,7 @@ ENTRY(hypercall_args_table)
.byte 1 /* do_tmem_op */
.byte 0 /* reserved for XenClient */
.byte 2 /* do_xenpmu_op */ /* 40 */
+ .byte 3 /* do_version_op */
.rept __HYPERVISOR_arch_0-(.-hypercall_args_table)
.byte 0 /* do_ni_hypercall */
.endr
diff --git a/xen/common/compat/kernel.c b/xen/common/compat/kernel.c
index df93fdd..7a7ca53 100644
--- a/xen/common/compat/kernel.c
+++ b/xen/common/compat/kernel.c
@@ -39,6 +39,8 @@ CHECK_TYPE(capabilities_info);
CHECK_TYPE(domain_handle);
+CHECK_TYPE(version_op_val);
+
#define xennmi_callback compat_nmi_callback
#define xennmi_callback_t compat_nmi_callback_t
diff --git a/xen/common/kernel.c b/xen/common/kernel.c
index a4a3c36..d614067 100644
--- a/xen/common/kernel.c
+++ b/xen/common/kernel.c
@@ -221,6 +221,47 @@ void __init do_initcalls(void)
#endif
+static int get_features(struct domain *d, xen_feature_info_t *fi)
+{
+ switch ( fi->submap_idx )
+ {
+ case 0:
+ fi->submap = (1U << XENFEAT_memory_op_vnode_supported);
+ if ( paging_mode_translate(d) )
+ fi->submap |=
+ (1U << XENFEAT_writable_page_tables) |
+ (1U << XENFEAT_auto_translated_physmap);
+ if ( is_hardware_domain(d) )
+ fi->submap |= 1U << XENFEAT_dom0;
+#ifdef CONFIG_X86
+ if ( VM_ASSIST(d, pae_extended_cr3) )
+ fi->submap |= (1U << XENFEAT_pae_pgdir_above_4gb);
+ switch ( d->guest_type )
+ {
+ case guest_type_pv:
+ fi->submap |= (1U << XENFEAT_mmu_pt_update_preserve_ad) |
+ (1U << XENFEAT_highmem_assist) |
+ (1U << XENFEAT_gnttab_map_avail_bits);
+ break;
+ case guest_type_pvh:
+ fi->submap |= (1U << XENFEAT_hvm_safe_pvclock) |
+ (1U << XENFEAT_supervisor_mode_kernel) |
+ (1U << XENFEAT_hvm_callback_vector);
+ break;
+ case guest_type_hvm:
+ fi->submap |= (1U << XENFEAT_hvm_safe_pvclock) |
+ (1U << XENFEAT_hvm_callback_vector) |
+ (1U << XENFEAT_hvm_pirqs);
+ break;
+ }
+#endif
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
/*
* Simple hypercalls.
*/
@@ -298,47 +339,14 @@ DO(xen_version)(int cmd, XEN_GUEST_HANDLE_PARAM(void) arg)
case XENVER_get_features:
{
xen_feature_info_t fi;
- struct domain *d = current->domain;
+ int rc;
if ( copy_from_guest(&fi, arg, 1) )
return -EFAULT;
- switch ( fi.submap_idx )
- {
- case 0:
- fi.submap = (1U << XENFEAT_memory_op_vnode_supported);
- if ( VM_ASSIST(d, pae_extended_cr3) )
- fi.submap |= (1U << XENFEAT_pae_pgdir_above_4gb);
- if ( paging_mode_translate(d) )
- fi.submap |=
- (1U << XENFEAT_writable_page_tables) |
- (1U << XENFEAT_auto_translated_physmap);
- if ( is_hardware_domain(d) )
- fi.submap |= 1U << XENFEAT_dom0;
-#ifdef CONFIG_X86
- switch ( d->guest_type )
- {
- case guest_type_pv:
- fi.submap |= (1U << XENFEAT_mmu_pt_update_preserve_ad) |
- (1U << XENFEAT_highmem_assist) |
- (1U << XENFEAT_gnttab_map_avail_bits);
- break;
- case guest_type_pvh:
- fi.submap |= (1U << XENFEAT_hvm_safe_pvclock) |
- (1U << XENFEAT_supervisor_mode_kernel) |
- (1U << XENFEAT_hvm_callback_vector);
- break;
- case guest_type_hvm:
- fi.submap |= (1U << XENFEAT_hvm_safe_pvclock) |
- (1U << XENFEAT_hvm_callback_vector) |
- (1U << XENFEAT_hvm_pirqs);
- break;
- }
-#endif
- break;
- default:
- return -EINVAL;
- }
+ rc = get_features(current->domain, &fi);
+ if ( rc )
+ return rc;
if ( __copy_to_guest(arg, &fi, 1) )
return -EFAULT;
@@ -381,6 +389,137 @@ DO(xen_version)(int cmd, XEN_GUEST_HANDLE_PARAM(void) arg)
return -ENOSYS;
}
+static const char *capabilities_info(unsigned int *len)
+{
+ static xen_capabilities_info_t __read_mostly cached_cap;
+ static unsigned int __read_mostly cached_cap_len;
+ static bool_t cached;
+
+ if ( unlikely(!cached) )
+ {
+ arch_get_xen_caps(&cached_cap);
+ cached_cap_len = strlen(cached_cap) + 1;
+ cached = 1;
+ }
+
+ *len = cached_cap_len;
+ return cached_cap;
+}
+
+/*
+ * Similar to HYPERVISOR_xen_version but with a sane interface
+ * (has a length, one can probe for the length) and with one less sub-ops:
+ * missing XENVER_compile_info.
+ */
+DO(version_op)(unsigned int cmd, XEN_GUEST_HANDLE_PARAM(void) arg,
+ unsigned int len)
+{
+ union {
+ xen_version_op_val_t val;
+ xen_feature_info_t fi;
+ } u = {};
+ unsigned int sz = 0;
+ const void *ptr = NULL;
+ int rc = xsm_version_op(XSM_OTHER, cmd);
+
+ /* We can safely return -EPERM! */
+ if ( rc )
+ return rc;
+
+ /*
+ * The HYPERVISOR_xen_version differs in that some return the value,
+ * and some copy it on back on argument. We follow the same rule for all
+ * sub-ops: return 0 on success, positive value of bytes returned, and
+ * always copy the result in arg. Yeey sanity!
+ */
+ switch ( cmd )
+ {
+ case XEN_VERSION_version:
+ sz = sizeof(xen_version_op_val_t);
+ u.val = (xen_major_version() << 16) | xen_minor_version();
+ break;
+
+ case XEN_VERSION_extraversion:
+ sz = strlen(xen_extra_version()) + 1;
+ ptr = xen_extra_version();
+ break;
+
+ case XEN_VERSION_capabilities:
+ ptr = capabilities_info(&sz);
+ break;
+
+ case XEN_VERSION_changeset:
+ sz = strlen(xen_changeset()) + 1;
+ ptr = xen_changeset();
+ break;
+
+ case XEN_VERSION_platform_parameters:
+ sz = sizeof(xen_version_op_val_t);
+ u.val = HYPERVISOR_VIRT_START;
+ break;
+
+ case XEN_VERSION_get_features:
+ sz = sizeof(xen_feature_info_t);
+
+ if ( guest_handle_is_null(arg) )
+ break;
+
+ if ( copy_from_guest(&u.fi, arg, 1) )
+ {
+ rc = -EFAULT;
+ break;
+ }
+ rc = get_features(current->domain, &u.fi);
+ break;
+
+ case XEN_VERSION_pagesize:
+ sz = sizeof(xen_version_op_val_t);
+ u.val = PAGE_SIZE;
+ break;
+
+ case XEN_VERSION_guest_handle:
+ sz = ARRAY_SIZE(current->domain->handle);
+ ptr = current->domain->handle;
+ break;
+
+ case XEN_VERSION_commandline:
+ sz = strlen(saved_cmdline) + 1;
+ ptr = saved_cmdline;
+ break;
+
+ default:
+ rc = -ENOSYS;
+ }
+
+ if ( rc )
+ return rc;
+
+ /*
+ * This hypercall also allows the client to probe. If it provides
+ * a NULL arg we will return the size of the space it has to
+ * allocate for the specific sub-op.
+ */
+ ASSERT(sz);
+ if ( guest_handle_is_null(arg) )
+ return sz;
+
+ if ( !rc )
+ {
+ unsigned int bytes = min(sz, len);
+
+ if ( copy_to_guest(arg, ptr ? : &u, bytes) )
+ rc = -EFAULT;
+
+ /*
+ * We return len (truncate) worth of data even if we fail.
+ */
+ if ( !rc && sz > len )
+ rc = -ENOBUFS;
+ }
+
+ return rc == 0 ? sz : rc;
+}
+
DO(nmi_op)(unsigned int cmd, XEN_GUEST_HANDLE_PARAM(void) arg)
{
struct xennmi_callback cb;
@@ -418,6 +557,21 @@ DO(ni_hypercall)(void)
return -ENOSYS;
}
+static int __init kernel_cache_init(void)
+{
+ unsigned int len;
+
+ /*
+ * Pre-allocate the cache so we do not have to worry about
+ * simultaneous invocations on safe_strcat by guests and the cache
+ * data becoming garbage.
+ */
+ (void)capabilities_info(&len);
+
+ return 0;
+}
+__initcall(kernel_cache_init);
+
/*
* Local variables:
* mode: C
diff --git a/xen/include/public/arch-arm.h b/xen/include/public/arch-arm.h
index 870bc3b..5f90718 100644
--- a/xen/include/public/arch-arm.h
+++ b/xen/include/public/arch-arm.h
@@ -128,6 +128,8 @@
* * VCPUOP_register_vcpu_info
* * VCPUOP_register_runstate_memory_area
*
+ * HYPERVISOR_version_op
+ * All generic sub-operations
*
* Other notes on the ARM ABI:
*
diff --git a/xen/include/public/version.h b/xen/include/public/version.h
index 24a582f..6e327bb 100644
--- a/xen/include/public/version.h
+++ b/xen/include/public/version.h
@@ -30,7 +30,14 @@
#include "xen.h"
-/* NB. All ops return zero on success, except XENVER_{version,pagesize} */
+/*
+ * There are two hypercalls mentioned in here. The XENVER_ are for
+ * HYPERCALL_xen_version (17), while VERSION_ are for the
+ * HYPERCALL_version_op (41).
+ *
+ * The subops are very similar except that the later hypercall has a
+ * sane interface.
+ */
/* arg == NULL; returns major:minor (16:16). */
#define XENVER_version 0
@@ -87,6 +94,67 @@ typedef struct xen_feature_info xen_feature_info_t;
#define XENVER_commandline 9
typedef char xen_commandline_t[1024];
+/*
+ * The HYPERCALL_version_op has a set of sub-ops which mirror the
+ * sub-ops of HYPERCALL_xen_version. However this hypercall differs
+ * radically from the former:
+ * - It returns the amount of bytes returned.
+ * - It will return -XEN_EPERM if the guest is not permitted
+ * (Albeit XEN_VERSION_version, XEN_VERSION_platform_parameters, and
+ * XEN_VERSION_get_features will always return an value as guest cannot
+ * survive without this information).
+ * - It will return the requested data in arg.
+ * - It requires an third argument (len) for the length of the
+ * arg. Naturally the arg has to fit the requested data otherwise
+ * -XEN_ENOBUFS is returned.
+ *
+ * It also offers an mechanism to probe for the amount of bytes an
+ * sub-op will require. Having the arg have an NULL handle will
+ * return the number of bytes requested for the operation. Or an
+ * negative value if an error is encountered.
+ */
+
+typedef uint64_t xen_version_op_val_t;
+DEFINE_XEN_GUEST_HANDLE(xen_version_op_val_t);
+
+/*
+ * arg == xen_version_op_val_t. Encoded as major:minor (31..16:15..0), while
+ * 63..32 are zero.
+ */
+#define XEN_VERSION_version 0
+
+/* arg == char. Contains NUL terminated utf-8 string. */
+#define XEN_VERSION_extraversion 1
+
+/* arg == char. Contains NUL terminated utf-8 string. */
+#define XEN_VERSION_capabilities 3
+
+/* arg == char. Contains NUL terminated utf-8 string. */
+#define XEN_VERSION_changeset 4
+
+/* arg == xen_version_op_val_t. */
+#define XEN_VERSION_platform_parameters 5
+
+/*
+ * arg = xen_feature_info_t - shares the same structure
+ * as the XENVER_get_features.
+ */
+#define XEN_VERSION_get_features 6
+
+/* arg == xen_version_op_val_t. */
+#define XEN_VERSION_pagesize 7
+
+/*
+ * arg == void.
+ *
+ * The toolstack fills it out for guest consumption. It is intended to hold
+ * the UUID of the guest.
+ */
+#define XEN_VERSION_guest_handle 8
+
+/* arg = char. Contains NUL terminated utf-8 string. */
+#define XEN_VERSION_commandline 9
+
#endif /* __XEN_PUBLIC_VERSION_H__ */
/*
diff --git a/xen/include/public/xen.h b/xen/include/public/xen.h
index 64ba7ab..1a99929 100644
--- a/xen/include/public/xen.h
+++ b/xen/include/public/xen.h
@@ -115,6 +115,7 @@ DEFINE_XEN_GUEST_HANDLE(xen_ulong_t);
#define __HYPERVISOR_tmem_op 38
#define __HYPERVISOR_xc_reserved_op 39 /* reserved for XenClient */
#define __HYPERVISOR_xenpmu_op 40
+#define __HYPERVISOR_version_op 41 /* supersedes xen_version (17) */
/* Architecture-specific hypercall definitions. */
#define __HYPERVISOR_arch_0 48
diff --git a/xen/include/xen/hypercall.h b/xen/include/xen/hypercall.h
index 0c8ae0e..e8d2b81 100644
--- a/xen/include/xen/hypercall.h
+++ b/xen/include/xen/hypercall.h
@@ -147,6 +147,10 @@ do_xenoprof_op(int op, XEN_GUEST_HANDLE_PARAM(void) arg);
extern long
do_xenpmu_op(unsigned int op, XEN_GUEST_HANDLE_PARAM(xen_pmu_params_t) arg);
+extern long
+do_version_op(unsigned int cmd,
+ XEN_GUEST_HANDLE_PARAM(void) arg, unsigned int len);
+
#ifdef CONFIG_COMPAT
extern int
diff --git a/xen/include/xsm/dummy.h b/xen/include/xsm/dummy.h
index abbe282..e5dad35 100644
--- a/xen/include/xsm/dummy.h
+++ b/xen/include/xsm/dummy.h
@@ -751,3 +751,24 @@ static XSM_INLINE int xsm_xen_version (XSM_DEFAULT_ARG
uint32_t op)
return xsm_default_action(XSM_PRIV, current->domain, NULL);
}
}
+
+static XSM_INLINE int xsm_version_op (XSM_DEFAULT_ARG uint32_t op)
+{
+ XSM_ASSERT_ACTION(XSM_OTHER);
+ switch ( op )
+ {
+ case XEN_VERSION_version:
+ case XEN_VERSION_platform_parameters:
+ case XEN_VERSION_get_features:
+ /* These MUST always be accessible to any guest by default. */
+ return 0;
+ case XEN_VERSION_extraversion:
+ case XEN_VERSION_capabilities:
+ case XEN_VERSION_pagesize:
+ case XEN_VERSION_guest_handle:
+ /* These can be accessible to a guest. */
+ return xsm_default_action(XSM_HOOK, current->domain, NULL);
+ default:
+ return xsm_default_action(XSM_PRIV, current->domain, NULL);
+ }
+}
diff --git a/xen/include/xsm/xsm.h b/xen/include/xsm/xsm.h
index 5ecbee0..ac80472 100644
--- a/xen/include/xsm/xsm.h
+++ b/xen/include/xsm/xsm.h
@@ -194,6 +194,7 @@ struct xsm_operations {
int (*pmu_op) (struct domain *d, unsigned int op);
#endif
int (*xen_version) (uint32_t cmd);
+ int (*version_op) (uint32_t cmd);
};
#ifdef CONFIG_XSM
@@ -737,6 +738,11 @@ static inline int xsm_xen_version (xsm_default_t def,
uint32_t op)
return xsm_ops->xen_version(op);
}
+static inline int xsm_version_op (xsm_default_t def, uint32_t op)
+{
+ return xsm_ops->version_op(op);
+}
+
#endif /* XSM_NO_WRAPPERS */
#ifdef CONFIG_MULTIBOOT
diff --git a/xen/xsm/dummy.c b/xen/xsm/dummy.c
index 9791ad4..776dd09 100644
--- a/xen/xsm/dummy.c
+++ b/xen/xsm/dummy.c
@@ -163,4 +163,5 @@ void xsm_fixup_ops (struct xsm_operations *ops)
set_to_dummy_if_null(ops, pmu_op);
#endif
set_to_dummy_if_null(ops, xen_version);
+ set_to_dummy_if_null(ops, version_op);
}
diff --git a/xen/xsm/flask/hooks.c b/xen/xsm/flask/hooks.c
index 2069cb3..1eaec58 100644
--- a/xen/xsm/flask/hooks.c
+++ b/xen/xsm/flask/hooks.c
@@ -1658,6 +1658,40 @@ static int flask_xen_version (uint32_t op)
}
}
+static int flask_version_op (uint32_t op)
+{
+ u32 dsid = domain_sid(current->domain);
+
+ switch ( op )
+ {
+ case XEN_VERSION_version:
+ case XEN_VERSION_platform_parameters:
+ case XEN_VERSION_get_features:
+ /* These MUST always be accessible to any guest by default. */
+ return 0;
+ case XEN_VERSION_extraversion:
+ return avc_has_perm(dsid, SECINITSID_XEN, SECCLASS_VERSION,
+ VERSION__EXTRAVERSION, NULL);
+ case XEN_VERSION_capabilities:
+ return avc_has_perm(dsid, SECINITSID_XEN, SECCLASS_VERSION,
+ VERSION__CAPABILITIES, NULL);
+ case XEN_VERSION_changeset:
+ return avc_has_perm(dsid, SECINITSID_XEN, SECCLASS_VERSION,
+ VERSION__CHANGESET, NULL);
+ case XEN_VERSION_pagesize:
+ return avc_has_perm(dsid, SECINITSID_XEN, SECCLASS_VERSION,
+ VERSION__PAGESIZE, NULL);
+ case XEN_VERSION_guest_handle:
+ return avc_has_perm(dsid, SECINITSID_XEN, SECCLASS_VERSION,
+ VERSION__GUEST_HANDLE, NULL);
+ case XEN_VERSION_commandline:
+ return avc_has_perm(dsid, SECINITSID_XEN, SECCLASS_VERSION,
+ VERSION__COMMANDLINE, NULL);
+ default:
+ return -EPERM;
+ }
+}
+
long do_flask_op(XEN_GUEST_HANDLE_PARAM(xsm_op_t) u_flask_op);
int compat_flask_op(XEN_GUEST_HANDLE_PARAM(xsm_op_t) u_flask_op);
@@ -1797,6 +1831,7 @@ static struct xsm_operations flask_ops = {
.pmu_op = flask_pmu_op,
#endif
.xen_version = flask_xen_version,
+ .version_op = flask_version_op,
};
static __init void flask_init(void)
diff --git a/xen/xsm/flask/policy/access_vectors
b/xen/xsm/flask/policy/access_vectors
index badcf1c..56600bb 100644
--- a/xen/xsm/flask/policy/access_vectors
+++ b/xen/xsm/flask/policy/access_vectors
@@ -496,12 +496,14 @@ class security
del_ocontext
}
-# Class version is used to describe the XENVER_ hypercall.
+# Class version is used to describe the XENVER_ and VERSION hypercall.
# Almost all sub-ops are described here - in the default case all of them
should
-# be allowed except the XENVER_commandline.
+# be allowed except the XENVER_commandline, VERSION_commandline, and
+# VERSION_changeset.
#
# The ones that are omitted are XENVER_version, XENVER_platform_parameters,
-# and XENVER_get_features - as they MUST always be returned to a guest.
+# XENVER_get_features, XEN_VERSION_version, XEN_VERSION_platform_parameters,
+# and XEN_VERSION_get_features - as they MUST always be returned to a guest.
#
class version
{
@@ -519,4 +521,17 @@ class version
xen_guest_handle
# Xen command line.
xen_commandline
+# --- VERSION hypercall ---
+# Extra informations (-unstable).
+ extraversion
+# Such as "xen-3.0-x86_64 xen-3.0-x86_32p hvm-3.0-x86_32 hvm-3.0-x86_32p
hvm-3.0-x86_64".
+ capabilities
+# Source code changeset.
+ changeset
+# Page size the hypervisor uses.
+ pagesize
+# An value that the control stack can choose.
+ guest_handle
+# Xen command line.
+ commandline
}
--
2.5.0
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