Subject: [PATCH v2 3/5] powerpc/mm: Validate address values against different region limits

From: "Aneesh Kumar K.V" <[email-masked]>
Date: Sun, 17 Mar 2019 21:18:25 +0530

This adds an explicit check in various functions.

Signed-off-by: Aneesh Kumar K.V <[email-masked]>
---
 arch/powerpc/mm/hash_utils_64.c  | 18 +++++++++++++++---
 arch/powerpc/mm/pgtable-hash64.c | 13 ++++++++++---
 arch/powerpc/mm/pgtable-radix.c  | 16 ++++++++++++++++
 arch/powerpc/mm/pgtable_64.c     |  5 +++++
 4 files changed, 46 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index c6b39e7694ba..ef0ca3bf555d 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -786,9 +786,16 @@ void resize_hpt_for_hotplug(unsigned long new_mem_size)
 
 int hash__create_section_mapping(unsigned long start, unsigned long end, int nid)
 {
-	int rc = htab_bolt_mapping(start, end, __pa(start),
-				   pgprot_val(PAGE_KERNEL), mmu_linear_psize,
-				   mmu_kernel_ssize);
+	int rc;
+
+	if (end >= H_VMALLOC_START) {
+		pr_warn("Outisde the supported range\n");
+		return -1;
+	}
+
+	rc = htab_bolt_mapping(start, end, __pa(start),
+			       pgprot_val(PAGE_KERNEL), mmu_linear_psize,
+			       mmu_kernel_ssize);
 
 	if (rc < 0) {
 		int rc2 = htab_remove_mapping(start, end, mmu_linear_psize,
@@ -929,6 +936,11 @@ static void __init htab_initialize(void)
 		DBG("creating mapping for region: %lx..%lx (prot: %lx)\n",
 		    base, size, prot);
 
+		if ((base + size) >= H_VMALLOC_START) {
+			pr_warn("Outisde the supported range\n");
+			continue;
+		}
+
 		BUG_ON(htab_bolt_mapping(base, base + size, __pa(base),
 				prot, mmu_linear_psize, mmu_kernel_ssize));
 	}
diff --git a/arch/powerpc/mm/pgtable-hash64.c b/arch/powerpc/mm/pgtable-hash64.c
index c08d49046a96..d934de4e2b3a 100644
--- a/arch/powerpc/mm/pgtable-hash64.c
+++ b/arch/powerpc/mm/pgtable-hash64.c
@@ -112,9 +112,16 @@ int __meminit hash__vmemmap_create_mapping(unsigned long start,
 				       unsigned long page_size,
 				       unsigned long phys)
 {
-	int rc = htab_bolt_mapping(start, start + page_size, phys,
-				   pgprot_val(PAGE_KERNEL),
-				   mmu_vmemmap_psize, mmu_kernel_ssize);
+	int rc;
+
+	if ((start + page_size) >= H_VMEMMAP_END) {
+		pr_warn("Outisde the supported range\n");
+		return -1;
+	}
+
+	rc = htab_bolt_mapping(start, start + page_size, phys,
+			       pgprot_val(PAGE_KERNEL),
+			       mmu_vmemmap_psize, mmu_kernel_ssize);
 	if (rc < 0) {
 		int rc2 = htab_remove_mapping(start, start + page_size,
 					      mmu_vmemmap_psize,
diff --git a/arch/powerpc/mm/pgtable-radix.c b/arch/powerpc/mm/pgtable-radix.c
index ba485fbd81f1..c9b24bf78819 100644
--- a/arch/powerpc/mm/pgtable-radix.c
+++ b/arch/powerpc/mm/pgtable-radix.c
@@ -334,6 +334,12 @@ void __init radix_init_pgtable(void)
 		 * page tables will be allocated within the range. No
 		 * need or a node (which we don't have yet).
 		 */
+
+		if ((reg->base + reg->size) >= RADIX_VMALLOC_START) {
+			pr_warn("Outisde the supported range\n");
+			continue;
+		}
+
 		WARN_ON(create_physical_mapping(reg->base,
 						reg->base + reg->size,
 						-1));
@@ -866,6 +872,11 @@ static void __meminit remove_pagetable(unsigned long start, unsigned long end)
 
 int __meminit radix__create_section_mapping(unsigned long start, unsigned long end, int nid)
 {
+	if (end >= RADIX_VMALLOC_START) {
+		pr_warn("Outisde the supported range\n");
+		return -1;
+	}
+
 	return create_physical_mapping(start, end, nid);
 }
 
@@ -893,6 +904,11 @@ int __meminit radix__vmemmap_create_mapping(unsigned long start,
 	int nid = early_pfn_to_nid(phys >> PAGE_SHIFT);
 	int ret;
 
+	if ((start + page_size) >= RADIX_VMEMMAP_END) {
+		pr_warn("Outisde the supported range\n");
+		return -1;
+	}
+
 	ret = __map_kernel_page_nid(start, phys, __pgprot(flags), page_size, nid);
 	BUG_ON(ret);
 
diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c
index 56068cac2a3c..72f58c076e26 100644
--- a/arch/powerpc/mm/pgtable_64.c
+++ b/arch/powerpc/mm/pgtable_64.c
@@ -121,6 +121,11 @@ void __iomem *__ioremap_at(phys_addr_t pa, void *ea, unsigned long size, pgprot_
 	if (pgprot_val(prot) & H_PAGE_4K_PFN)
 		return NULL;
 
+	if ((ea + size) >= (void *)IOREMAP_END) {
+		pr_warn("Outisde the supported range\n");
+		return NULL;
+	}
+
 	WARN_ON(pa & ~PAGE_MASK);
 	WARN_ON(((unsigned long)ea) & ~PAGE_MASK);
 	WARN_ON(size & ~PAGE_MASK);
-- 
2.20.1