// SPDX-License-Identifier: GPL-2.0 /* * This file contains common tag-based KASAN code. * * Copyright (c) 2018 Google, Inc. * Copyright (c) 2020 Google, Inc. */ #include <linux/init.h> #include <linux/kasan.h> #include <linux/kernel.h> #include <linux/memory.h> #include <linux/mm.h> #include <linux/static_key.h> #include <linux/string.h> #include <linux/types.h> #include "kasan.h" void kasan_set_free_info(struct kmem_cache *cache, void *object, u8 tag) { struct kasan_alloc_meta *alloc_meta; u8 idx = 0; alloc_meta = kasan_get_alloc_meta(cache, object); if (!alloc_meta) return; #ifdef CONFIG_KASAN_TAGS_IDENTIFY idx = alloc_meta->free_track_idx; alloc_meta->free_pointer_tag[idx] = tag; alloc_meta->free_track_idx = (idx + 1) % KASAN_NR_FREE_STACKS; #endif kasan_set_track(&alloc_meta->free_track[idx], GFP_NOWAIT); } struct kasan_track *kasan_get_free_track(struct kmem_cache *cache, void *object, u8 tag) { struct kasan_alloc_meta *alloc_meta; int i = 0; alloc_meta = kasan_get_alloc_meta(cache, object); if (!alloc_meta) return NULL; #ifdef CONFIG_KASAN_TAGS_IDENTIFY for (i = 0; i < KASAN_NR_FREE_STACKS; i++) { if (alloc_meta->free_pointer_tag[i] == tag) break; } if (i == KASAN_NR_FREE_STACKS) i = alloc_meta->free_track_idx; #endif return &alloc_meta->free_track[i]; }