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Diffstat (limited to '0003-VT-d-Fix-else-vs-endif-misplacement.patch')
-rw-r--r--0003-VT-d-Fix-else-vs-endif-misplacement.patch70
1 files changed, 70 insertions, 0 deletions
diff --git a/0003-VT-d-Fix-else-vs-endif-misplacement.patch b/0003-VT-d-Fix-else-vs-endif-misplacement.patch
new file mode 100644
index 0000000..2e7f78d
--- /dev/null
+++ b/0003-VT-d-Fix-else-vs-endif-misplacement.patch
@@ -0,0 +1,70 @@
+From 6b1864afc14d484cdbc9754ce3172ac3dc189846 Mon Sep 17 00:00:00 2001
+From: Andrew Cooper <andrew.cooper3@citrix.com>
+Date: Tue, 30 Jan 2024 14:38:38 +0100
+Subject: [PATCH 03/10] VT-d: Fix "else" vs "#endif" misplacement
+
+In domain_pgd_maddr() the "#endif" is misplaced with respect to "else". This
+generates incorrect logic when CONFIG_HVM is compiled out, as the "else" body
+is executed unconditionally.
+
+Rework the logic to use IS_ENABLED() instead of explicit #ifdef-ary, as it's
+clearer to follow. This in turn involves adjusting p2m_get_pagetable() to
+compile when CONFIG_HVM is disabled.
+
+This is XSA-450 / CVE-2023-46840.
+
+Fixes: 033ff90aa9c1 ("x86/P2M: p2m_{alloc,free}_ptp() and p2m_alloc_table() are HVM-only")
+Reported-by: Teddy Astie <teddy.astie@vates.tech>
+Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
+Reviewed-by: Jan Beulich <jbeulich@suse.com>
+master commit: cc6ba68edf6dcd18c3865e7d7c0f1ed822796426
+master date: 2024-01-30 14:29:15 +0100
+---
+ xen/arch/x86/include/asm/p2m.h | 9 ++++++++-
+ xen/drivers/passthrough/vtd/iommu.c | 4 +---
+ 2 files changed, 9 insertions(+), 4 deletions(-)
+
+diff --git a/xen/arch/x86/include/asm/p2m.h b/xen/arch/x86/include/asm/p2m.h
+index cd43d8621a..4f691533d5 100644
+--- a/xen/arch/x86/include/asm/p2m.h
++++ b/xen/arch/x86/include/asm/p2m.h
+@@ -447,7 +447,14 @@ static inline bool_t p2m_is_altp2m(const struct p2m_domain *p2m)
+ return p2m->p2m_class == p2m_alternate;
+ }
+
+-#define p2m_get_pagetable(p2m) ((p2m)->phys_table)
++#ifdef CONFIG_HVM
++static inline pagetable_t p2m_get_pagetable(const struct p2m_domain *p2m)
++{
++ return p2m->phys_table;
++}
++#else
++pagetable_t p2m_get_pagetable(const struct p2m_domain *p2m);
++#endif
+
+ /*
+ * Ensure any deferred p2m TLB flush has been completed on all VCPUs.
+diff --git a/xen/drivers/passthrough/vtd/iommu.c b/xen/drivers/passthrough/vtd/iommu.c
+index b4c11a6b48..908b3ba6ee 100644
+--- a/xen/drivers/passthrough/vtd/iommu.c
++++ b/xen/drivers/passthrough/vtd/iommu.c
+@@ -441,15 +441,13 @@ static paddr_t domain_pgd_maddr(struct domain *d, paddr_t pgd_maddr,
+
+ if ( pgd_maddr )
+ /* nothing */;
+-#ifdef CONFIG_HVM
+- else if ( iommu_use_hap_pt(d) )
++ else if ( IS_ENABLED(CONFIG_HVM) && iommu_use_hap_pt(d) )
+ {
+ pagetable_t pgt = p2m_get_pagetable(p2m_get_hostp2m(d));
+
+ pgd_maddr = pagetable_get_paddr(pgt);
+ }
+ else
+-#endif
+ {
+ if ( !hd->arch.vtd.pgd_maddr )
+ {
+--
+2.43.0
+