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Diffstat (limited to '')
-rw-r--r-- | lib/test_kasan_module.c | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/lib/test_kasan_module.c b/lib/test_kasan_module.c new file mode 100644 index 000000000..2d68db6ae --- /dev/null +++ b/lib/test_kasan_module.c @@ -0,0 +1,111 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * + * Copyright (c) 2014 Samsung Electronics Co., Ltd. + * Author: Andrey Ryabinin <a.ryabinin@samsung.com> + */ + +#define pr_fmt(fmt) "kasan test: %s " fmt, __func__ + +#include <linux/mman.h> +#include <linux/module.h> +#include <linux/printk.h> +#include <linux/slab.h> +#include <linux/uaccess.h> + +#include "../mm/kasan/kasan.h" + +#define OOB_TAG_OFF (IS_ENABLED(CONFIG_KASAN_GENERIC) ? 0 : KASAN_SHADOW_SCALE_SIZE) + +static noinline void __init copy_user_test(void) +{ + char *kmem; + char __user *usermem; + size_t size = 10; + int unused; + + kmem = kmalloc(size, GFP_KERNEL); + if (!kmem) + return; + + usermem = (char __user *)vm_mmap(NULL, 0, PAGE_SIZE, + PROT_READ | PROT_WRITE | PROT_EXEC, + MAP_ANONYMOUS | MAP_PRIVATE, 0); + if (IS_ERR(usermem)) { + pr_err("Failed to allocate user memory\n"); + kfree(kmem); + return; + } + + pr_info("out-of-bounds in copy_from_user()\n"); + unused = copy_from_user(kmem, usermem, size + 1 + OOB_TAG_OFF); + + pr_info("out-of-bounds in copy_to_user()\n"); + unused = copy_to_user(usermem, kmem, size + 1 + OOB_TAG_OFF); + + pr_info("out-of-bounds in __copy_from_user()\n"); + unused = __copy_from_user(kmem, usermem, size + 1 + OOB_TAG_OFF); + + pr_info("out-of-bounds in __copy_to_user()\n"); + unused = __copy_to_user(usermem, kmem, size + 1 + OOB_TAG_OFF); + + pr_info("out-of-bounds in __copy_from_user_inatomic()\n"); + unused = __copy_from_user_inatomic(kmem, usermem, size + 1 + OOB_TAG_OFF); + + pr_info("out-of-bounds in __copy_to_user_inatomic()\n"); + unused = __copy_to_user_inatomic(usermem, kmem, size + 1 + OOB_TAG_OFF); + + pr_info("out-of-bounds in strncpy_from_user()\n"); + unused = strncpy_from_user(kmem, usermem, size + 1 + OOB_TAG_OFF); + + vm_munmap((unsigned long)usermem, PAGE_SIZE); + kfree(kmem); +} + +static struct kasan_rcu_info { + int i; + struct rcu_head rcu; +} *global_rcu_ptr; + +static noinline void __init kasan_rcu_reclaim(struct rcu_head *rp) +{ + struct kasan_rcu_info *fp = container_of(rp, + struct kasan_rcu_info, rcu); + + kfree(fp); + fp->i = 1; +} + +static noinline void __init kasan_rcu_uaf(void) +{ + struct kasan_rcu_info *ptr; + + pr_info("use-after-free in kasan_rcu_reclaim\n"); + ptr = kmalloc(sizeof(struct kasan_rcu_info), GFP_KERNEL); + if (!ptr) { + pr_err("Allocation failed\n"); + return; + } + + global_rcu_ptr = rcu_dereference_protected(ptr, NULL); + call_rcu(&global_rcu_ptr->rcu, kasan_rcu_reclaim); +} + + +static int __init test_kasan_module_init(void) +{ + /* + * Temporarily enable multi-shot mode. Otherwise, we'd only get a + * report for the first case. + */ + bool multishot = kasan_save_enable_multi_shot(); + + copy_user_test(); + kasan_rcu_uaf(); + + kasan_restore_multi_shot(multishot); + return -EAGAIN; +} + +module_init(test_kasan_module_init); +MODULE_LICENSE("GPL"); |