kasan: group vmalloc code

This is a preparatory commit for the upcoming addition of a new hardware
tag-based (MTE-based) KASAN mode.

Group all vmalloc-related function declarations in include/linux/kasan.h,
and their implementations in mm/kasan/common.c.

No functional changes.

Link: https://lkml.kernel.org/r/80a6fdd29b039962843bd6cf22ce2643a7c8904e.1606161801.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Marco Elver <elver@google.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Vasily Gorbik <gor@linux.ibm.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>

diff --git a/include/linux/kasan.h b/include/linux/kasan.h
index 30d343b4a40a599f6095e172a4a506b22826e966..59538e795df4be935a923ecd9c4d4de769992d9c 100644 (file)
--- a/include/linux/kasan.h
+++ b/include/linux/kasan.h
@@ -75,19 +75,6 @@ struct kasan_cache {
        int free_meta_offset;
 };
 
-/*
- * These functions provide a special case to support backing module
- * allocations with real shadow memory. With KASAN vmalloc, the special
- * case is unnecessary, as the work is handled in the generic case.
- */
-#ifndef CONFIG_KASAN_VMALLOC
-int kasan_module_alloc(void *addr, size_t size);
-void kasan_free_shadow(const struct vm_struct *vm);
-#else
-static inline int kasan_module_alloc(void *addr, size_t size) { return 0; }
-static inline void kasan_free_shadow(const struct vm_struct *vm) {}
-#endif
-
 int kasan_add_zero_shadow(void *start, unsigned long size);
 void kasan_remove_zero_shadow(void *start, unsigned long size);
 
@@ -156,9 +143,6 @@ static inline bool kasan_slab_free(struct kmem_cache *s, void *object,
        return false;
 }
 
-static inline int kasan_module_alloc(void *addr, size_t size) { return 0; }
-static inline void kasan_free_shadow(const struct vm_struct *vm) {}
-
 static inline int kasan_add_zero_shadow(void *start, unsigned long size)
 {
        return 0;
@@ -211,13 +195,16 @@ static inline void *kasan_reset_tag(const void *addr)
 #endif /* CONFIG_KASAN_SW_TAGS */
 
 #ifdef CONFIG_KASAN_VMALLOC
+
 int kasan_populate_vmalloc(unsigned long addr, unsigned long size);
 void kasan_poison_vmalloc(const void *start, unsigned long size);
 void kasan_unpoison_vmalloc(const void *start, unsigned long size);
 void kasan_release_vmalloc(unsigned long start, unsigned long end,
                           unsigned long free_region_start,
                           unsigned long free_region_end);
-#else
+
+#else /* CONFIG_KASAN_VMALLOC */
+
 static inline int kasan_populate_vmalloc(unsigned long start,
                                        unsigned long size)
 {
@@ -232,7 +219,25 @@ static inline void kasan_release_vmalloc(unsigned long start,
                                         unsigned long end,
                                         unsigned long free_region_start,
                                         unsigned long free_region_end) {}
-#endif
+
+#endif /* CONFIG_KASAN_VMALLOC */
+
+#if defined(CONFIG_KASAN) && !defined(CONFIG_KASAN_VMALLOC)
+
+/*
+ * These functions provide a special case to support backing module
+ * allocations with real shadow memory. With KASAN vmalloc, the special
+ * case is unnecessary, as the work is handled in the generic case.
+ */
+int kasan_module_alloc(void *addr, size_t size);
+void kasan_free_shadow(const struct vm_struct *vm);
+
+#else /* CONFIG_KASAN && !CONFIG_KASAN_VMALLOC */
+
+static inline int kasan_module_alloc(void *addr, size_t size) { return 0; }
+static inline void kasan_free_shadow(const struct vm_struct *vm) {}
+
+#endif /* CONFIG_KASAN && !CONFIG_KASAN_VMALLOC */
 
 #ifdef CONFIG_KASAN_INLINE
 void kasan_non_canonical_hook(unsigned long addr);

diff --git a/mm/kasan/common.c b/mm/kasan/common.c
index 33d863f55db19f8814ad5f1de126cac8dc34eded..89e5ef9417a7992a7c3dc5bc6d7f7414fc1abd9b 100644 (file)
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -536,44 +536,6 @@ void kasan_kfree_large(void *ptr, unsigned long ip)
        /* The object will be poisoned by page_alloc. */
 }
 
-#ifndef CONFIG_KASAN_VMALLOC
-int kasan_module_alloc(void *addr, size_t size)
-{
-       void *ret;
-       size_t scaled_size;
-       size_t shadow_size;
-       unsigned long shadow_start;
-
-       shadow_start = (unsigned long)kasan_mem_to_shadow(addr);
-       scaled_size = (size + KASAN_SHADOW_MASK) >> KASAN_SHADOW_SCALE_SHIFT;
-       shadow_size = round_up(scaled_size, PAGE_SIZE);
-
-       if (WARN_ON(!PAGE_ALIGNED(shadow_start)))
-               return -EINVAL;
-
-       ret = __vmalloc_node_range(shadow_size, 1, shadow_start,
-                       shadow_start + shadow_size,
-                       GFP_KERNEL,
-                       PAGE_KERNEL, VM_NO_GUARD, NUMA_NO_NODE,
-                       __builtin_return_address(0));
-
-       if (ret) {
-               __memset(ret, KASAN_SHADOW_INIT, shadow_size);
-               find_vm_area(addr)->flags |= VM_KASAN;
-               kmemleak_ignore(ret);
-               return 0;
-       }
-
-       return -ENOMEM;
-}
-
-void kasan_free_shadow(const struct vm_struct *vm)
-{
-       if (vm->flags & VM_KASAN)
-               vfree(kasan_mem_to_shadow(vm->addr));
-}
-#endif
-
 #ifdef CONFIG_MEMORY_HOTPLUG
 static bool shadow_mapped(unsigned long addr)
 {
@@ -685,6 +647,7 @@ core_initcall(kasan_memhotplug_init);
 #endif
 
 #ifdef CONFIG_KASAN_VMALLOC
+
 static int kasan_populate_vmalloc_pte(pte_t *ptep, unsigned long addr,
                                      void *unused)
 {
@@ -923,4 +886,43 @@ void kasan_release_vmalloc(unsigned long start, unsigned long end,
                                       (unsigned long)shadow_end);
        }
 }
+
+#else /* CONFIG_KASAN_VMALLOC */
+
+int kasan_module_alloc(void *addr, size_t size)
+{
+       void *ret;
+       size_t scaled_size;
+       size_t shadow_size;
+       unsigned long shadow_start;
+
+       shadow_start = (unsigned long)kasan_mem_to_shadow(addr);
+       scaled_size = (size + KASAN_SHADOW_MASK) >> KASAN_SHADOW_SCALE_SHIFT;
+       shadow_size = round_up(scaled_size, PAGE_SIZE);
+
+       if (WARN_ON(!PAGE_ALIGNED(shadow_start)))
+               return -EINVAL;
+
+       ret = __vmalloc_node_range(shadow_size, 1, shadow_start,
+                       shadow_start + shadow_size,
+                       GFP_KERNEL,
+                       PAGE_KERNEL, VM_NO_GUARD, NUMA_NO_NODE,
+                       __builtin_return_address(0));
+
+       if (ret) {
+               __memset(ret, KASAN_SHADOW_INIT, shadow_size);
+               find_vm_area(addr)->flags |= VM_KASAN;
+               kmemleak_ignore(ret);
+               return 0;
+       }
+
+       return -ENOMEM;
+}
+
+void kasan_free_shadow(const struct vm_struct *vm)
+{
+       if (vm->flags & VM_KASAN)
+               vfree(kasan_mem_to_shadow(vm->addr));
+}
+
 #endif