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-rw-r--r--system/xen/xsa/xsa248.patch164
1 files changed, 0 insertions, 164 deletions
diff --git a/system/xen/xsa/xsa248.patch b/system/xen/xsa/xsa248.patch
deleted file mode 100644
index 966c16e043..0000000000
--- a/system/xen/xsa/xsa248.patch
+++ /dev/null
@@ -1,164 +0,0 @@
-From: Jan Beulich <jbeulich@suse.com>
-Subject: x86/mm: don't wrongly set page ownership
-
-PV domains can obtain mappings of any pages owned by the correct domain,
-including ones that aren't actually assigned as "normal" RAM, but used
-by Xen internally. At the moment such "internal" pages marked as owned
-by a guest include pages used to track logdirty bits, as well as p2m
-pages and the "unpaged pagetable" for HVM guests. Since the PV memory
-management and shadow code conflict in their use of struct page_info
-fields, and since shadow code is being used for log-dirty handling for
-PV domains, pages coming from the shadow pool must, for PV domains, not
-have the domain set as their owner.
-
-While the change could be done conditionally for just the PV case in
-shadow code, do it unconditionally (and for consistency also for HAP),
-just to be on the safe side.
-
-There's one special case though for shadow code: The page table used for
-running a HVM guest in unpaged mode is subject to get_page() (in
-set_shadow_status()) and hence must have its owner set.
-
-This is XSA-248.
-
-Signed-off-by: Jan Beulich <jbeulich@suse.com>
-Reviewed-by: Tim Deegan <tim@xen.org>
-Reviewed-by: George Dunlap <george.dunlap@citrix.com>
----
-v2: Drop PGC_page_table related pieces.
-
---- a/xen/arch/x86/mm/hap/hap.c
-+++ b/xen/arch/x86/mm/hap/hap.c
-@@ -286,8 +286,7 @@ static struct page_info *hap_alloc_p2m_p
- {
- d->arch.paging.hap.total_pages--;
- d->arch.paging.hap.p2m_pages++;
-- page_set_owner(pg, d);
-- pg->count_info |= 1;
-+ ASSERT(!page_get_owner(pg) && !(pg->count_info & PGC_count_mask));
- }
- else if ( !d->arch.paging.p2m_alloc_failed )
- {
-@@ -302,21 +301,23 @@ static struct page_info *hap_alloc_p2m_p
-
- static void hap_free_p2m_page(struct domain *d, struct page_info *pg)
- {
-+ struct domain *owner = page_get_owner(pg);
-+
- /* This is called both from the p2m code (which never holds the
- * paging lock) and the log-dirty code (which always does). */
- paging_lock_recursive(d);
-
-- ASSERT(page_get_owner(pg) == d);
-- /* Should have just the one ref we gave it in alloc_p2m_page() */
-- if ( (pg->count_info & PGC_count_mask) != 1 ) {
-- HAP_ERROR("Odd p2m page %p count c=%#lx t=%"PRtype_info"\n",
-- pg, pg->count_info, pg->u.inuse.type_info);
-+ /* Should still have no owner and count zero. */
-+ if ( owner || (pg->count_info & PGC_count_mask) )
-+ {
-+ HAP_ERROR("d%d: Odd p2m page %"PRI_mfn" d=%d c=%lx t=%"PRtype_info"\n",
-+ d->domain_id, mfn_x(page_to_mfn(pg)),
-+ owner ? owner->domain_id : DOMID_INVALID,
-+ pg->count_info, pg->u.inuse.type_info);
- WARN();
-+ pg->count_info &= ~PGC_count_mask;
-+ page_set_owner(pg, NULL);
- }
-- pg->count_info &= ~PGC_count_mask;
-- /* Free should not decrement domain's total allocation, since
-- * these pages were allocated without an owner. */
-- page_set_owner(pg, NULL);
- d->arch.paging.hap.p2m_pages--;
- d->arch.paging.hap.total_pages++;
- hap_free(d, page_to_mfn(pg));
---- a/xen/arch/x86/mm/shadow/common.c
-+++ b/xen/arch/x86/mm/shadow/common.c
-@@ -1503,32 +1503,29 @@ shadow_alloc_p2m_page(struct domain *d)
- pg = mfn_to_page(shadow_alloc(d, SH_type_p2m_table, 0));
- d->arch.paging.shadow.p2m_pages++;
- d->arch.paging.shadow.total_pages--;
-+ ASSERT(!page_get_owner(pg) && !(pg->count_info & PGC_count_mask));
-
- paging_unlock(d);
-
-- /* Unlike shadow pages, mark p2m pages as owned by the domain.
-- * Marking the domain as the owner would normally allow the guest to
-- * create mappings of these pages, but these p2m pages will never be
-- * in the domain's guest-physical address space, and so that is not
-- * believed to be a concern. */
-- page_set_owner(pg, d);
-- pg->count_info |= 1;
- return pg;
- }
-
- static void
- shadow_free_p2m_page(struct domain *d, struct page_info *pg)
- {
-- ASSERT(page_get_owner(pg) == d);
-- /* Should have just the one ref we gave it in alloc_p2m_page() */
-- if ( (pg->count_info & PGC_count_mask) != 1 )
-+ struct domain *owner = page_get_owner(pg);
-+
-+ /* Should still have no owner and count zero. */
-+ if ( owner || (pg->count_info & PGC_count_mask) )
- {
-- SHADOW_ERROR("Odd p2m page count c=%#lx t=%"PRtype_info"\n",
-+ SHADOW_ERROR("d%d: Odd p2m page %"PRI_mfn" d=%d c=%lx t=%"PRtype_info"\n",
-+ d->domain_id, mfn_x(page_to_mfn(pg)),
-+ owner ? owner->domain_id : DOMID_INVALID,
- pg->count_info, pg->u.inuse.type_info);
-+ pg->count_info &= ~PGC_count_mask;
-+ page_set_owner(pg, NULL);
- }
-- pg->count_info &= ~PGC_count_mask;
- pg->u.sh.type = SH_type_p2m_table; /* p2m code reuses type-info */
-- page_set_owner(pg, NULL);
-
- /* This is called both from the p2m code (which never holds the
- * paging lock) and the log-dirty code (which always does). */
-@@ -3132,7 +3129,9 @@ int shadow_enable(struct domain *d, u32
- e = __map_domain_page(pg);
- write_32bit_pse_identmap(e);
- unmap_domain_page(e);
-+ pg->count_info = 1;
- pg->u.inuse.type_info = PGT_l2_page_table | 1 | PGT_validated;
-+ page_set_owner(pg, d);
- }
-
- paging_lock(d);
-@@ -3170,7 +3169,11 @@ int shadow_enable(struct domain *d, u32
- if ( rv != 0 && !pagetable_is_null(p2m_get_pagetable(p2m)) )
- p2m_teardown(p2m);
- if ( rv != 0 && pg != NULL )
-+ {
-+ pg->count_info &= ~PGC_count_mask;
-+ page_set_owner(pg, NULL);
- shadow_free_p2m_page(d, pg);
-+ }
- domain_unpause(d);
- return rv;
- }
-@@ -3279,7 +3282,22 @@ out:
-
- /* Must be called outside the lock */
- if ( unpaged_pagetable )
-+ {
-+ if ( page_get_owner(unpaged_pagetable) == d &&
-+ (unpaged_pagetable->count_info & PGC_count_mask) == 1 )
-+ {
-+ unpaged_pagetable->count_info &= ~PGC_count_mask;
-+ page_set_owner(unpaged_pagetable, NULL);
-+ }
-+ /* Complain here in cases where shadow_free_p2m_page() won't. */
-+ else if ( !page_get_owner(unpaged_pagetable) &&
-+ !(unpaged_pagetable->count_info & PGC_count_mask) )
-+ SHADOW_ERROR("d%d: Odd unpaged pt %"PRI_mfn" c=%lx t=%"PRtype_info"\n",
-+ d->domain_id, mfn_x(page_to_mfn(unpaged_pagetable)),
-+ unpaged_pagetable->count_info,
-+ unpaged_pagetable->u.inuse.type_info);
- shadow_free_p2m_page(d, unpaged_pagetable);
-+ }
- }
-
- void shadow_final_teardown(struct domain *d)
generated by cgit v1.2.3 (git 2.26.2) at 2024-11-10 07:49:36 +0000