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-rw-r--r--include/linux/kasan.h5
-rw-r--r--include/linux/vmalloc.h1
-rw-r--r--kernel/module.c2
-rw-r--r--mm/kasan/kasan.c14
-rw-r--r--mm/vmalloc.c1
5 files changed, 16 insertions, 7 deletions
diff --git a/include/linux/kasan.h b/include/linux/kasan.h
index 72ba725ddf9c..5fa48a21d73e 100644
--- a/include/linux/kasan.h
+++ b/include/linux/kasan.h
@@ -5,6 +5,7 @@
struct kmem_cache;
struct page;
+struct vm_struct;
#ifdef CONFIG_KASAN
@@ -52,7 +53,7 @@ void kasan_slab_free(struct kmem_cache *s, void *object);
#define MODULE_ALIGN (PAGE_SIZE << KASAN_SHADOW_SCALE_SHIFT)
int kasan_module_alloc(void *addr, size_t size);
-void kasan_module_free(void *addr);
+void kasan_free_shadow(const struct vm_struct *vm);
#else /* CONFIG_KASAN */
@@ -82,7 +83,7 @@ static inline void kasan_slab_alloc(struct kmem_cache *s, void *object) {}
static inline void kasan_slab_free(struct kmem_cache *s, void *object) {}
static inline int kasan_module_alloc(void *addr, size_t size) { return 0; }
-static inline void kasan_module_free(void *addr) {}
+static inline void kasan_free_shadow(const struct vm_struct *vm) {}
#endif /* CONFIG_KASAN */
diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index 7d7acb35603d..0ec598381f97 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -17,6 +17,7 @@ struct vm_area_struct; /* vma defining user mapping in mm_types.h */
#define VM_VPAGES 0x00000010 /* buffer for pages was vmalloc'ed */
#define VM_UNINITIALIZED 0x00000020 /* vm_struct is not fully initialized */
#define VM_NO_GUARD 0x00000040 /* don't add guard page */
+#define VM_KASAN 0x00000080 /* has allocated kasan shadow memory */
/* bits [20..32] reserved for arch specific ioremap internals */
/*
diff --git a/kernel/module.c b/kernel/module.c
index cc93cf68653c..b3d634ed06c9 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -56,7 +56,6 @@
#include <linux/async.h>
#include <linux/percpu.h>
#include <linux/kmemleak.h>
-#include <linux/kasan.h>
#include <linux/jump_label.h>
#include <linux/pfn.h>
#include <linux/bsearch.h>
@@ -1814,7 +1813,6 @@ static void unset_module_init_ro_nx(struct module *mod) { }
void __weak module_memfree(void *module_region)
{
vfree(module_region);
- kasan_module_free(module_region);
}
void __weak module_arch_cleanup(struct module *mod)
diff --git a/mm/kasan/kasan.c b/mm/kasan/kasan.c
index 78fee632a7ee..936d81661c47 100644
--- a/mm/kasan/kasan.c
+++ b/mm/kasan/kasan.c
@@ -29,6 +29,7 @@
#include <linux/stacktrace.h>
#include <linux/string.h>
#include <linux/types.h>
+#include <linux/vmalloc.h>
#include <linux/kasan.h>
#include "kasan.h"
@@ -414,12 +415,19 @@ int kasan_module_alloc(void *addr, size_t size)
GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO,
PAGE_KERNEL, VM_NO_GUARD, NUMA_NO_NODE,
__builtin_return_address(0));
- return ret ? 0 : -ENOMEM;
+
+ if (ret) {
+ find_vm_area(addr)->flags |= VM_KASAN;
+ return 0;
+ }
+
+ return -ENOMEM;
}
-void kasan_module_free(void *addr)
+void kasan_free_shadow(const struct vm_struct *vm)
{
- vfree(kasan_mem_to_shadow(addr));
+ if (vm->flags & VM_KASAN)
+ vfree(kasan_mem_to_shadow(vm->addr));
}
static void register_global(struct kasan_global *global)
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 35b25e1340ca..49abccf29a29 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -1418,6 +1418,7 @@ struct vm_struct *remove_vm_area(const void *addr)
spin_unlock(&vmap_area_lock);
vmap_debug_free_range(va->va_start, va->va_end);
+ kasan_free_shadow(vm);
free_unmap_vmap_area(va);
vm->size -= PAGE_SIZE;