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 6747abe8bc08..da886746c1f5 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_UNLIST 0x00000020 /* vm_struct is not listed in vmlist */ #define VM_LOWMEM 0x00000040 /* Tracking of direct mapped lowmem */ +#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 2e43628573c0..ec9101b14670 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -57,7 +57,6 @@ #include #include #include -#include #include #include #include @@ -1852,7 +1851,6 @@ static void unset_module_init_ro_nx(struct module *mod) { } void __weak module_free(struct module *mod, 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 #include #include +#include #include #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 51a66939827c..0f7b5eec4c7a 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include #include @@ -1559,6 +1560,7 @@ 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;