kasan: rename kasan_zero_page to kasan_early_shadow_page
authorAndrey Konovalov <andreyknvl@google.com>
Fri, 28 Dec 2018 08:30:01 +0000 (00:30 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 28 Dec 2018 20:11:43 +0000 (12:11 -0800)
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>
arch/arm64/mm/kasan_init.c
arch/s390/mm/dump_pagetables.c
arch/s390/mm/kasan_init.c
arch/x86/mm/dump_pagetables.c
arch/x86/mm/kasan_init_64.c
arch/xtensa/mm/kasan_init.c
include/linux/kasan.h
mm/kasan/init.c

index 63527e5..4ebc194 100644 (file)
@@ -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 */
index 363f647..3b93ba0 100644 (file)
@@ -111,11 +111,12 @@ static void note_page(struct seq_file *m, struct pg_state *st,
 }
 
 #ifdef CONFIG_KASAN
-static void note_kasan_zero_page(struct seq_file *m, struct pg_state *st)
+static void note_kasan_early_shadow_page(struct seq_file *m,
+                                               struct pg_state *st)
 {
        unsigned int prot;
 
-       prot = pte_val(*kasan_zero_pte) &
+       prot = pte_val(*kasan_early_shadow_pte) &
                (_PAGE_PROTECT | _PAGE_INVALID | _PAGE_NOEXEC);
        note_page(m, st, prot, 4);
 }
@@ -154,8 +155,8 @@ static void walk_pmd_level(struct seq_file *m, struct pg_state *st,
        int i;
 
 #ifdef CONFIG_KASAN
-       if ((pud_val(*pud) & PAGE_MASK) == __pa(kasan_zero_pmd)) {
-               note_kasan_zero_page(m, st);
+       if ((pud_val(*pud) & PAGE_MASK) == __pa(kasan_early_shadow_pmd)) {
+               note_kasan_early_shadow_page(m, st);
                return;
        }
 #endif
@@ -185,8 +186,8 @@ static void walk_pud_level(struct seq_file *m, struct pg_state *st,
        int i;
 
 #ifdef CONFIG_KASAN
-       if ((p4d_val(*p4d) & PAGE_MASK) == __pa(kasan_zero_pud)) {
-               note_kasan_zero_page(m, st);
+       if ((p4d_val(*p4d) & PAGE_MASK) == __pa(kasan_early_shadow_pud)) {
+               note_kasan_early_shadow_page(m, st);
                return;
        }
 #endif
@@ -215,8 +216,8 @@ static void walk_p4d_level(struct seq_file *m, struct pg_state *st,
        int i;
 
 #ifdef CONFIG_KASAN
-       if ((pgd_val(*pgd) & PAGE_MASK) == __pa(kasan_zero_p4d)) {
-               note_kasan_zero_page(m, st);
+       if ((pgd_val(*pgd) & PAGE_MASK) == __pa(kasan_early_shadow_p4d)) {
+               note_kasan_early_shadow_page(m, st);
                return;
        }
 #endif
index acb9645..bac5c27 100644 (file)
@@ -107,7 +107,8 @@ static void __init kasan_early_vmemmap_populate(unsigned long address,
                        if (mode == POPULATE_ZERO_SHADOW &&
                            IS_ALIGNED(address, PGDIR_SIZE) &&
                            end - address >= PGDIR_SIZE) {
-                               pgd_populate(&init_mm, pg_dir, kasan_zero_p4d);
+                               pgd_populate(&init_mm, pg_dir,
+                                               kasan_early_shadow_p4d);
                                address = (address + PGDIR_SIZE) & PGDIR_MASK;
                                continue;
                        }
@@ -120,7 +121,8 @@ static void __init kasan_early_vmemmap_populate(unsigned long address,
                        if (mode == POPULATE_ZERO_SHADOW &&
                            IS_ALIGNED(address, P4D_SIZE) &&
                            end - address >= P4D_SIZE) {
-                               p4d_populate(&init_mm, p4_dir, kasan_zero_pud);
+                               p4d_populate(&init_mm, p4_dir,
+                                               kasan_early_shadow_pud);
                                address = (address + P4D_SIZE) & P4D_MASK;
                                continue;
                        }
@@ -133,7 +135,8 @@ static void __init kasan_early_vmemmap_populate(unsigned long address,
                        if (mode == POPULATE_ZERO_SHADOW &&
                            IS_ALIGNED(address, PUD_SIZE) &&
                            end - address >= PUD_SIZE) {
-                               pud_populate(&init_mm, pu_dir, kasan_zero_pmd);
+                               pud_populate(&init_mm, pu_dir,
+                                               kasan_early_shadow_pmd);
                                address = (address + PUD_SIZE) & PUD_MASK;
                                continue;
                        }
@@ -146,7 +149,8 @@ static void __init kasan_early_vmemmap_populate(unsigned long address,
                        if (mode == POPULATE_ZERO_SHADOW &&
                            IS_ALIGNED(address, PMD_SIZE) &&
                            end - address >= PMD_SIZE) {
-                               pmd_populate(&init_mm, pm_dir, kasan_zero_pte);
+                               pmd_populate(&init_mm, pm_dir,
+                                               kasan_early_shadow_pte);
                                address = (address + PMD_SIZE) & PMD_MASK;
                                continue;
                        }
@@ -188,7 +192,7 @@ static void __init kasan_early_vmemmap_populate(unsigned long address,
                                pte_val(*pt_dir) = __pa(page) | pgt_prot;
                                break;
                        case POPULATE_ZERO_SHADOW:
-                               page = kasan_zero_page;
+                               page = kasan_early_shadow_page;
                                pte_val(*pt_dir) = __pa(page) | pgt_prot_zero;
                                break;
                        }
@@ -256,14 +260,14 @@ void __init kasan_early_init(void)
        unsigned long vmax;
        unsigned long pgt_prot = pgprot_val(PAGE_KERNEL_RO);
        pte_t pte_z;
-       pmd_t pmd_z = __pmd(__pa(kasan_zero_pte) | _SEGMENT_ENTRY);
-       pud_t pud_z = __pud(__pa(kasan_zero_pmd) | _REGION3_ENTRY);
-       p4d_t p4d_z = __p4d(__pa(kasan_zero_pud) | _REGION2_ENTRY);
+       pmd_t pmd_z = __pmd(__pa(kasan_early_shadow_pte) | _SEGMENT_ENTRY);
+       pud_t pud_z = __pud(__pa(kasan_early_shadow_pmd) | _REGION3_ENTRY);
+       p4d_t p4d_z = __p4d(__pa(kasan_early_shadow_pud) | _REGION2_ENTRY);
 
        kasan_early_detect_facilities();
        if (!has_nx)
                pgt_prot &= ~_PAGE_NOEXEC;
-       pte_z = __pte(__pa(kasan_zero_page) | pgt_prot);
+       pte_z = __pte(__pa(kasan_early_shadow_page) | pgt_prot);
 
        memsize = get_mem_detect_end();
        if (!memsize)
@@ -292,10 +296,13 @@ void __init kasan_early_init(void)
        }
 
        /* init kasan zero shadow */
-       crst_table_init((unsigned long *)kasan_zero_p4d, p4d_val(p4d_z));
-       crst_table_init((unsigned long *)kasan_zero_pud, pud_val(pud_z));
-       crst_table_init((unsigned long *)kasan_zero_pmd, pmd_val(pmd_z));
-       memset64((u64 *)kasan_zero_pte, pte_val(pte_z), PTRS_PER_PTE);
+       crst_table_init((unsigned long *)kasan_early_shadow_p4d,
+                               p4d_val(p4d_z));
+       crst_table_init((unsigned long *)kasan_early_shadow_pud,
+                               pud_val(pud_z));
+       crst_table_init((unsigned long *)kasan_early_shadow_pmd,
+                               pmd_val(pmd_z));
+       memset64((u64 *)kasan_early_shadow_pte, pte_val(pte_z), PTRS_PER_PTE);
 
        shadow_alloc_size = memsize >> KASAN_SHADOW_SCALE_SHIFT;
        pgalloc_low = round_up((unsigned long)_end, _SEGMENT_SIZE);
index abcb8d0..e3cdc85 100644 (file)
@@ -377,7 +377,7 @@ static void walk_pte_level(struct seq_file *m, struct pg_state *st, pmd_t addr,
 
 /*
  * This is an optimization for KASAN=y case. Since all kasan page tables
- * eventually point to the kasan_zero_page we could call note_page()
+ * eventually point to the kasan_early_shadow_page we could call note_page()
  * right away without walking through lower level page tables. This saves
  * us dozens of seconds (minutes for 5-level config) while checking for
  * W+X mapping or reading kernel_page_tables debugfs file.
@@ -385,10 +385,11 @@ static void walk_pte_level(struct seq_file *m, struct pg_state *st, pmd_t addr,
 static inline bool kasan_page_table(struct seq_file *m, struct pg_state *st,
                                void *pt)
 {
-       if (__pa(pt) == __pa(kasan_zero_pmd) ||
-           (pgtable_l5_enabled() && __pa(pt) == __pa(kasan_zero_p4d)) ||
-           __pa(pt) == __pa(kasan_zero_pud)) {
-               pgprotval_t prot = pte_flags(kasan_zero_pte[0]);
+       if (__pa(pt) == __pa(kasan_early_shadow_pmd) ||
+           (pgtable_l5_enabled() &&
+                       __pa(pt) == __pa(kasan_early_shadow_p4d)) ||
+           __pa(pt) == __pa(kasan_early_shadow_pud)) {
+               pgprotval_t prot = pte_flags(kasan_early_shadow_pte[0]);
                note_page(m, st, __pgprot(prot), 0, 5);
                return true;
        }
index 04a9cf6..462fde8 100644 (file)
@@ -211,7 +211,8 @@ static void __init kasan_early_p4d_populate(pgd_t *pgd,
        unsigned long next;
 
        if (pgd_none(*pgd)) {
-               pgd_entry = __pgd(_KERNPG_TABLE | __pa_nodebug(kasan_zero_p4d));
+               pgd_entry = __pgd(_KERNPG_TABLE |
+                                       __pa_nodebug(kasan_early_shadow_p4d));
                set_pgd(pgd, pgd_entry);
        }
 
@@ -222,7 +223,8 @@ static void __init kasan_early_p4d_populate(pgd_t *pgd,
                if (!p4d_none(*p4d))
                        continue;
 
-               p4d_entry = __p4d(_KERNPG_TABLE | __pa_nodebug(kasan_zero_pud));
+               p4d_entry = __p4d(_KERNPG_TABLE |
+                                       __pa_nodebug(kasan_early_shadow_pud));
                set_p4d(p4d, p4d_entry);
        } while (p4d++, addr = next, addr != end && p4d_none(*p4d));
 }
@@ -261,10 +263,11 @@ static struct notifier_block kasan_die_notifier = {
 void __init kasan_early_init(void)
 {
        int i;
-       pteval_t pte_val = __pa_nodebug(kasan_zero_page) | __PAGE_KERNEL | _PAGE_ENC;
-       pmdval_t pmd_val = __pa_nodebug(kasan_zero_pte) | _KERNPG_TABLE;
-       pudval_t pud_val = __pa_nodebug(kasan_zero_pmd) | _KERNPG_TABLE;
-       p4dval_t p4d_val = __pa_nodebug(kasan_zero_pud) | _KERNPG_TABLE;
+       pteval_t pte_val = __pa_nodebug(kasan_early_shadow_page) |
+                               __PAGE_KERNEL | _PAGE_ENC;
+       pmdval_t pmd_val = __pa_nodebug(kasan_early_shadow_pte) | _KERNPG_TABLE;
+       pudval_t pud_val = __pa_nodebug(kasan_early_shadow_pmd) | _KERNPG_TABLE;
+       p4dval_t p4d_val = __pa_nodebug(kasan_early_shadow_pud) | _KERNPG_TABLE;
 
        /* Mask out unsupported __PAGE_KERNEL bits: */
        pte_val &= __default_kernel_pte_mask;
@@ -273,16 +276,16 @@ void __init kasan_early_init(void)
        p4d_val &= __default_kernel_pte_mask;
 
        for (i = 0; i < PTRS_PER_PTE; i++)
-               kasan_zero_pte[i] = __pte(pte_val);
+               kasan_early_shadow_pte[i] = __pte(pte_val);
 
        for (i = 0; i < PTRS_PER_PMD; i++)
-               kasan_zero_pmd[i] = __pmd(pmd_val);
+               kasan_early_shadow_pmd[i] = __pmd(pmd_val);
 
        for (i = 0; i < PTRS_PER_PUD; i++)
-               kasan_zero_pud[i] = __pud(pud_val);
+               kasan_early_shadow_pud[i] = __pud(pud_val);
 
        for (i = 0; pgtable_l5_enabled() && i < PTRS_PER_P4D; i++)
-               kasan_zero_p4d[i] = __p4d(p4d_val);
+               kasan_early_shadow_p4d[i] = __p4d(p4d_val);
 
        kasan_map_early_shadow(early_top_pgt);
        kasan_map_early_shadow(init_top_pgt);
@@ -326,7 +329,7 @@ void __init kasan_init(void)
 
        clear_pgds(KASAN_SHADOW_START & PGDIR_MASK, KASAN_SHADOW_END);
 
-       kasan_populate_zero_shadow((void *)(KASAN_SHADOW_START & PGDIR_MASK),
+       kasan_populate_early_shadow((void *)(KASAN_SHADOW_START & PGDIR_MASK),
                        kasan_mem_to_shadow((void *)PAGE_OFFSET));
 
        for (i = 0; i < E820_MAX_ENTRIES; i++) {
@@ -338,41 +341,41 @@ void __init kasan_init(void)
 
        shadow_cpu_entry_begin = (void *)CPU_ENTRY_AREA_BASE;
        shadow_cpu_entry_begin = kasan_mem_to_shadow(shadow_cpu_entry_begin);
-       shadow_cpu_entry_begin = (void *)round_down((unsigned long)shadow_cpu_entry_begin,
-                                               PAGE_SIZE);
+       shadow_cpu_entry_begin = (void *)round_down(
+                       (unsigned long)shadow_cpu_entry_begin, PAGE_SIZE);
 
        shadow_cpu_entry_end = (void *)(CPU_ENTRY_AREA_BASE +
                                        CPU_ENTRY_AREA_MAP_SIZE);
        shadow_cpu_entry_end = kasan_mem_to_shadow(shadow_cpu_entry_end);
-       shadow_cpu_entry_end = (void *)round_up((unsigned long)shadow_cpu_entry_end,
-                                       PAGE_SIZE);
+       shadow_cpu_entry_end = (void *)round_up(
+                       (unsigned long)shadow_cpu_entry_end, PAGE_SIZE);
 
-       kasan_populate_zero_shadow(
+       kasan_populate_early_shadow(
                kasan_mem_to_shadow((void *)PAGE_OFFSET + MAXMEM),
                shadow_cpu_entry_begin);
 
        kasan_populate_shadow((unsigned long)shadow_cpu_entry_begin,
                              (unsigned long)shadow_cpu_entry_end, 0);
 
-       kasan_populate_zero_shadow(shadow_cpu_entry_end,
-                               kasan_mem_to_shadow((void *)__START_KERNEL_map));
+       kasan_populate_early_shadow(shadow_cpu_entry_end,
+                       kasan_mem_to_shadow((void *)__START_KERNEL_map));
 
        kasan_populate_shadow((unsigned long)kasan_mem_to_shadow(_stext),
                              (unsigned long)kasan_mem_to_shadow(_end),
                              early_pfn_to_nid(__pa(_stext)));
 
-       kasan_populate_zero_shadow(kasan_mem_to_shadow((void *)MODULES_END),
-                               (void *)KASAN_SHADOW_END);
+       kasan_populate_early_shadow(kasan_mem_to_shadow((void *)MODULES_END),
+                                       (void *)KASAN_SHADOW_END);
 
        load_cr3(init_top_pgt);
        __flush_tlb_all();
 
        /*
-        * kasan_zero_page has been used as early shadow memory, thus it may
-        * contain some garbage. Now we can clear and write protect it, since
-        * after the TLB flush no one should write to it.
+        * kasan_early_shadow_page has been used as early shadow memory, thus
+        * it may contain some garbage. Now we can clear and write protect it,
+        * since after the TLB flush no one should write to it.
         */
-       memset(kasan_zero_page, 0, PAGE_SIZE);
+       memset(kasan_early_shadow_page, 0, PAGE_SIZE);
        for (i = 0; i < PTRS_PER_PTE; i++) {
                pte_t pte;
                pgprot_t prot;
@@ -380,8 +383,8 @@ void __init kasan_init(void)
                prot = __pgprot(__PAGE_KERNEL_RO | _PAGE_ENC);
                pgprot_val(prot) &= __default_kernel_pte_mask;
 
-               pte = __pte(__pa(kasan_zero_page) | pgprot_val(prot));
-               set_pte(&kasan_zero_pte[i], pte);
+               pte = __pte(__pa(kasan_early_shadow_page) | pgprot_val(prot));
+               set_pte(&kasan_early_shadow_pte[i], pte);
        }
        /* Flush TLBs again to be sure that write protection applied. */
        __flush_tlb_all();
index 6b95ca4..1734cda 100644 (file)
@@ -24,12 +24,13 @@ void __init kasan_early_init(void)
        int i;
 
        for (i = 0; i < PTRS_PER_PTE; ++i)
-               set_pte(kasan_zero_pte + i,
-                       mk_pte(virt_to_page(kasan_zero_page), PAGE_KERNEL));
+               set_pte(kasan_early_shadow_pte + i,
+                       mk_pte(virt_to_page(kasan_early_shadow_page),
+                               PAGE_KERNEL));
 
        for (vaddr = 0; vaddr < KASAN_SHADOW_SIZE; vaddr += PMD_SIZE, ++pmd) {
                BUG_ON(!pmd_none(*pmd));
-               set_pmd(pmd, __pmd((unsigned long)kasan_zero_pte));
+               set_pmd(pmd, __pmd((unsigned long)kasan_early_shadow_pte));
        }
        early_trap_init();
 }
@@ -80,13 +81,16 @@ void __init kasan_init(void)
        populate(kasan_mem_to_shadow((void *)VMALLOC_START),
                 kasan_mem_to_shadow((void *)XCHAL_KSEG_BYPASS_VADDR));
 
-       /* Write protect kasan_zero_page and zero-initialize it again. */
+       /*
+        * Write protect kasan_early_shadow_page and zero-initialize it again.
+        */
        for (i = 0; i < PTRS_PER_PTE; ++i)
-               set_pte(kasan_zero_pte + i,
-                       mk_pte(virt_to_page(kasan_zero_page), PAGE_KERNEL_RO));
+               set_pte(kasan_early_shadow_pte + i,
+                       mk_pte(virt_to_page(kasan_early_shadow_page),
+                               PAGE_KERNEL_RO));
 
        local_flush_tlb_all();
-       memset(kasan_zero_page, 0, PAGE_SIZE);
+       memset(kasan_early_shadow_page, 0, PAGE_SIZE);
 
        /* At this point kasan is fully initialized. Enable error messages. */
        current->kasan_depth = 0;
index b66fdf5..ec22d54 100644 (file)
@@ -14,13 +14,13 @@ struct task_struct;
 #include <asm/kasan.h>
 #include <asm/pgtable.h>
 
-extern unsigned char kasan_zero_page[PAGE_SIZE];
-extern pte_t kasan_zero_pte[PTRS_PER_PTE];
-extern pmd_t kasan_zero_pmd[PTRS_PER_PMD];
-extern pud_t kasan_zero_pud[PTRS_PER_PUD];
-extern p4d_t kasan_zero_p4d[MAX_PTRS_PER_P4D];
+extern unsigned char kasan_early_shadow_page[PAGE_SIZE];
+extern pte_t kasan_early_shadow_pte[PTRS_PER_PTE];
+extern pmd_t kasan_early_shadow_pmd[PTRS_PER_PMD];
+extern pud_t kasan_early_shadow_pud[PTRS_PER_PUD];
+extern p4d_t kasan_early_shadow_p4d[MAX_PTRS_PER_P4D];
 
-int kasan_populate_zero_shadow(const void *shadow_start,
+int kasan_populate_early_shadow(const void *shadow_start,
                                const void *shadow_end);
 
 static inline void *kasan_mem_to_shadow(const void *addr)
index c7550eb..2b21d37 100644 (file)
  *   - Latter it reused it as zero shadow to cover large ranges of memory
  *     that allowed to access, but not handled by kasan (vmalloc/vmemmap ...).
  */
-unsigned char kasan_zero_page[PAGE_SIZE] __page_aligned_bss;
+unsigned char kasan_early_shadow_page[PAGE_SIZE] __page_aligned_bss;
 
 #if CONFIG_PGTABLE_LEVELS > 4
-p4d_t kasan_zero_p4d[MAX_PTRS_PER_P4D] __page_aligned_bss;
+p4d_t kasan_early_shadow_p4d[MAX_PTRS_PER_P4D] __page_aligned_bss;
 static inline bool kasan_p4d_table(pgd_t pgd)
 {
-       return pgd_page(pgd) == virt_to_page(lm_alias(kasan_zero_p4d));
+       return pgd_page(pgd) == virt_to_page(lm_alias(kasan_early_shadow_p4d));
 }
 #else
 static inline bool kasan_p4d_table(pgd_t pgd)
@@ -45,10 +45,10 @@ static inline bool kasan_p4d_table(pgd_t pgd)
 }
 #endif
 #if CONFIG_PGTABLE_LEVELS > 3
-pud_t kasan_zero_pud[PTRS_PER_PUD] __page_aligned_bss;
+pud_t kasan_early_shadow_pud[PTRS_PER_PUD] __page_aligned_bss;
 static inline bool kasan_pud_table(p4d_t p4d)
 {
-       return p4d_page(p4d) == virt_to_page(lm_alias(kasan_zero_pud));
+       return p4d_page(p4d) == virt_to_page(lm_alias(kasan_early_shadow_pud));
 }
 #else
 static inline bool kasan_pud_table(p4d_t p4d)
@@ -57,10 +57,10 @@ static inline bool kasan_pud_table(p4d_t p4d)
 }
 #endif
 #if CONFIG_PGTABLE_LEVELS > 2
-pmd_t kasan_zero_pmd[PTRS_PER_PMD] __page_aligned_bss;
+pmd_t kasan_early_shadow_pmd[PTRS_PER_PMD] __page_aligned_bss;
 static inline bool kasan_pmd_table(pud_t pud)
 {
-       return pud_page(pud) == virt_to_page(lm_alias(kasan_zero_pmd));
+       return pud_page(pud) == virt_to_page(lm_alias(kasan_early_shadow_pmd));
 }
 #else
 static inline bool kasan_pmd_table(pud_t pud)
@@ -68,16 +68,16 @@ static inline bool kasan_pmd_table(pud_t pud)
        return 0;
 }
 #endif
-pte_t kasan_zero_pte[PTRS_PER_PTE] __page_aligned_bss;
+pte_t kasan_early_shadow_pte[PTRS_PER_PTE] __page_aligned_bss;
 
 static inline bool kasan_pte_table(pmd_t pmd)
 {
-       return pmd_page(pmd) == virt_to_page(lm_alias(kasan_zero_pte));
+       return pmd_page(pmd) == virt_to_page(lm_alias(kasan_early_shadow_pte));
 }
 
-static inline bool kasan_zero_page_entry(pte_t pte)
+static inline bool kasan_early_shadow_page_entry(pte_t pte)
 {
-       return pte_page(pte) == virt_to_page(lm_alias(kasan_zero_page));
+       return pte_page(pte) == virt_to_page(lm_alias(kasan_early_shadow_page));
 }
 
 static __init void *early_alloc(size_t size, int node)
@@ -92,7 +92,8 @@ static void __ref zero_pte_populate(pmd_t *pmd, unsigned long addr,
        pte_t *pte = pte_offset_kernel(pmd, addr);
        pte_t zero_pte;
 
-       zero_pte = pfn_pte(PFN_DOWN(__pa_symbol(kasan_zero_page)), PAGE_KERNEL);
+       zero_pte = pfn_pte(PFN_DOWN(__pa_symbol(kasan_early_shadow_page)),
+                               PAGE_KERNEL);
        zero_pte = pte_wrprotect(zero_pte);
 
        while (addr + PAGE_SIZE <= end) {
@@ -112,7 +113,8 @@ static int __ref zero_pmd_populate(pud_t *pud, unsigned long addr,
                next = pmd_addr_end(addr, end);
 
                if (IS_ALIGNED(addr, PMD_SIZE) && end - addr >= PMD_SIZE) {
-                       pmd_populate_kernel(&init_mm, pmd, lm_alias(kasan_zero_pte));
+                       pmd_populate_kernel(&init_mm, pmd,
+                                       lm_alias(kasan_early_shadow_pte));
                        continue;
                }
 
@@ -145,9 +147,11 @@ static int __ref zero_pud_populate(p4d_t *p4d, unsigned long addr,
                if (IS_ALIGNED(addr, PUD_SIZE) && end - addr >= PUD_SIZE) {
                        pmd_t *pmd;
 
-                       pud_populate(&init_mm, pud, lm_alias(kasan_zero_pmd));
+                       pud_populate(&init_mm, pud,
+                                       lm_alias(kasan_early_shadow_pmd));
                        pmd = pmd_offset(pud, addr);
-                       pmd_populate_kernel(&init_mm, pmd, lm_alias(kasan_zero_pte));
+                       pmd_populate_kernel(&init_mm, pmd,
+                                       lm_alias(kasan_early_shadow_pte));
                        continue;
                }
 
@@ -181,12 +185,14 @@ static int __ref zero_p4d_populate(pgd_t *pgd, unsigned long addr,
                        pud_t *pud;
                        pmd_t *pmd;
 
-                       p4d_populate(&init_mm, p4d, lm_alias(kasan_zero_pud));
+                       p4d_populate(&init_mm, p4d,
+                                       lm_alias(kasan_early_shadow_pud));
                        pud = pud_offset(p4d, addr);
-                       pud_populate(&init_mm, pud, lm_alias(kasan_zero_pmd));
+                       pud_populate(&init_mm, pud,
+                                       lm_alias(kasan_early_shadow_pmd));
                        pmd = pmd_offset(pud, addr);
                        pmd_populate_kernel(&init_mm, pmd,
-                                               lm_alias(kasan_zero_pte));
+                                       lm_alias(kasan_early_shadow_pte));
                        continue;
                }
 
@@ -209,13 +215,13 @@ static int __ref zero_p4d_populate(pgd_t *pgd, unsigned long addr,
 }
 
 /**
- * kasan_populate_zero_shadow - populate shadow memory region with
- *                               kasan_zero_page
+ * kasan_populate_early_shadow - populate shadow memory region with
+ *                               kasan_early_shadow_page
  * @shadow_start - start of the memory range to populate
  * @shadow_end   - end of the memory range to populate
  */
-int __ref kasan_populate_zero_shadow(const void *shadow_start,
-                               const void *shadow_end)
+int __ref kasan_populate_early_shadow(const void *shadow_start,
+                                       const void *shadow_end)
 {
        unsigned long addr = (unsigned long)shadow_start;
        unsigned long end = (unsigned long)shadow_end;
@@ -231,7 +237,7 @@ int __ref kasan_populate_zero_shadow(const void *shadow_start,
                        pmd_t *pmd;
 
                        /*
-                        * kasan_zero_pud should be populated with pmds
+                        * kasan_early_shadow_pud should be populated with pmds
                         * at this moment.
                         * [pud,pmd]_populate*() below needed only for
                         * 3,2 - level page tables where we don't have
@@ -241,21 +247,25 @@ int __ref kasan_populate_zero_shadow(const void *shadow_start,
                         * The ifndef is required to avoid build breakage.
                         *
                         * With 5level-fixup.h, pgd_populate() is not nop and
-                        * we reference kasan_zero_p4d. It's not defined
+                        * we reference kasan_early_shadow_p4d. It's not defined
                         * unless 5-level paging enabled.
                         *
                         * The ifndef can be dropped once all KASAN-enabled
                         * architectures will switch to pgtable-nop4d.h.
                         */
 #ifndef __ARCH_HAS_5LEVEL_HACK
-                       pgd_populate(&init_mm, pgd, lm_alias(kasan_zero_p4d));
+                       pgd_populate(&init_mm, pgd,
+                                       lm_alias(kasan_early_shadow_p4d));
 #endif
                        p4d = p4d_offset(pgd, addr);
-                       p4d_populate(&init_mm, p4d, lm_alias(kasan_zero_pud));
+                       p4d_populate(&init_mm, p4d,
+                                       lm_alias(kasan_early_shadow_pud));
                        pud = pud_offset(p4d, addr);
-                       pud_populate(&init_mm, pud, lm_alias(kasan_zero_pmd));
+                       pud_populate(&init_mm, pud,
+                                       lm_alias(kasan_early_shadow_pmd));
                        pmd = pmd_offset(pud, addr);
-                       pmd_populate_kernel(&init_mm, pmd, lm_alias(kasan_zero_pte));
+                       pmd_populate_kernel(&init_mm, pmd,
+                                       lm_alias(kasan_early_shadow_pte));
                        continue;
                }
 
@@ -350,7 +360,7 @@ static void kasan_remove_pte_table(pte_t *pte, unsigned long addr,
                if (!pte_present(*pte))
                        continue;
 
-               if (WARN_ON(!kasan_zero_page_entry(*pte)))
+               if (WARN_ON(!kasan_early_shadow_page_entry(*pte)))
                        continue;
                pte_clear(&init_mm, addr, pte);
        }
@@ -480,7 +490,7 @@ int kasan_add_zero_shadow(void *start, unsigned long size)
            WARN_ON(size % (KASAN_SHADOW_SCALE_SIZE * PAGE_SIZE)))
                return -EINVAL;
 
-       ret = kasan_populate_zero_shadow(shadow_start, shadow_end);
+       ret = kasan_populate_early_shadow(shadow_start, shadow_end);
        if (ret)
                kasan_remove_zero_shadow(shadow_start,
                                        size >> KASAN_SHADOW_SCALE_SHIFT);