kasan: rename kasan_zero_page to kasan_early_shadow_page

With tag based KASAN mode the early shadow value is 0xff and not 0x00, so
this patch renames kasan_zero_(page|pte|pmd|pud|p4d) to
kasan_early_shadow_(page|pte|pmd|pud|p4d) to avoid confusion.

Link: http://lkml.kernel.org/r/3fed313280ebf4f88645f5b89ccbc066d320e177.1544099024.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 24 insertions, 19 deletions

diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c
index 63527e585aac..4ebc19422931 100644
--- a/arch/arm64/mm/kasan_init.c
+++ b/arch/arm64/mm/kasan_init.c
@@ -47,8 +47,9 @@ static pte_t *__init kasan_pte_offset(pmd_t *pmdp, unsigned long addr, int node,
 				      bool early)
 {
 	if (pmd_none(READ_ONCE(*pmdp))) {
-		phys_addr_t pte_phys = early ? __pa_symbol(kasan_zero_pte)
-					     : kasan_alloc_zeroed_page(node);
+		phys_addr_t pte_phys = early ?
+				__pa_symbol(kasan_early_shadow_pte)
+					: kasan_alloc_zeroed_page(node);
 		__pmd_populate(pmdp, pte_phys, PMD_TYPE_TABLE);
 	}
 
@@ -60,8 +61,9 @@ static pmd_t *__init kasan_pmd_offset(pud_t *pudp, unsigned long addr, int node,
 				      bool early)
 {
 	if (pud_none(READ_ONCE(*pudp))) {
-		phys_addr_t pmd_phys = early ? __pa_symbol(kasan_zero_pmd)
-					     : kasan_alloc_zeroed_page(node);
+		phys_addr_t pmd_phys = early ?
+				__pa_symbol(kasan_early_shadow_pmd)
+					: kasan_alloc_zeroed_page(node);
 		__pud_populate(pudp, pmd_phys, PMD_TYPE_TABLE);
 	}
 
@@ -72,8 +74,9 @@ static pud_t *__init kasan_pud_offset(pgd_t *pgdp, unsigned long addr, int node,
 				      bool early)
 {
 	if (pgd_none(READ_ONCE(*pgdp))) {
-		phys_addr_t pud_phys = early ? __pa_symbol(kasan_zero_pud)
-					     : kasan_alloc_zeroed_page(node);
+		phys_addr_t pud_phys = early ?
+				__pa_symbol(kasan_early_shadow_pud)
+					: kasan_alloc_zeroed_page(node);
 		__pgd_populate(pgdp, pud_phys, PMD_TYPE_TABLE);
 	}
 
@@ -87,8 +90,9 @@ static void __init kasan_pte_populate(pmd_t *pmdp, unsigned long addr,
 	pte_t *ptep = kasan_pte_offset(pmdp, addr, node, early);
 
 	do {
-		phys_addr_t page_phys = early ? __pa_symbol(kasan_zero_page)
-					      : kasan_alloc_zeroed_page(node);
+		phys_addr_t page_phys = early ?
+				__pa_symbol(kasan_early_shadow_page)
+					: kasan_alloc_zeroed_page(node);
 		next = addr + PAGE_SIZE;
 		set_pte(ptep, pfn_pte(__phys_to_pfn(page_phys), PAGE_KERNEL));
 	} while (ptep++, addr = next, addr != end && pte_none(READ_ONCE(*ptep)));
@@ -205,14 +209,14 @@ void __init kasan_init(void)
 	kasan_map_populate(kimg_shadow_start, kimg_shadow_end,
 			   early_pfn_to_nid(virt_to_pfn(lm_alias(_text))));
 
-	kasan_populate_zero_shadow((void *)KASAN_SHADOW_START,
-				   (void *)mod_shadow_start);
-	kasan_populate_zero_shadow((void *)kimg_shadow_end,
-				   kasan_mem_to_shadow((void *)PAGE_OFFSET));
+	kasan_populate_early_shadow((void *)KASAN_SHADOW_START,
+				    (void *)mod_shadow_start);
+	kasan_populate_early_shadow((void *)kimg_shadow_end,
+				    kasan_mem_to_shadow((void *)PAGE_OFFSET));
 
 	if (kimg_shadow_start > mod_shadow_end)
-		kasan_populate_zero_shadow((void *)mod_shadow_end,
-					   (void *)kimg_shadow_start);
+		kasan_populate_early_shadow((void *)mod_shadow_end,
+					    (void *)kimg_shadow_start);
 
 	for_each_memblock(memory, reg) {
 		void *start = (void *)__phys_to_virt(reg->base);
@@ -227,14 +231,15 @@ void __init kasan_init(void)
 	}
 
 	/*
-	 * KAsan may reuse the contents of kasan_zero_pte directly, so we
-	 * should make sure that it maps the zero page read-only.
+	 * KAsan may reuse the contents of kasan_early_shadow_pte directly,
+	 * so we should make sure that it maps the zero page read-only.
 	 */
 	for (i = 0; i < PTRS_PER_PTE; i++)
-		set_pte(&kasan_zero_pte[i],
-			pfn_pte(sym_to_pfn(kasan_zero_page), PAGE_KERNEL_RO));
+		set_pte(&kasan_early_shadow_pte[i],
+			pfn_pte(sym_to_pfn(kasan_early_shadow_page),
+				PAGE_KERNEL_RO));
 
-	memset(kasan_zero_page, 0, PAGE_SIZE);
+	memset(kasan_early_shadow_page, 0, PAGE_SIZE);
 	cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
 
 	/* At this point kasan is fully initialized. Enable error messages */