diff options
Diffstat (limited to 'lib/test_user_copy.c')
| -rw-r--r-- | lib/test_user_copy.c | 196 |
1 files changed, 0 insertions, 196 deletions
diff --git a/lib/test_user_copy.c b/lib/test_user_copy.c deleted file mode 100644 index e161f0498f42..000000000000 --- a/lib/test_user_copy.c +++ /dev/null @@ -1,196 +0,0 @@ -/* - * Kernel module for testing copy_to/from_user infrastructure. - * - * Copyright 2013 Google Inc. All Rights Reserved - * - * Authors: - * Kees Cook <keescook@chromium.org> - * - * This software is licensed under the terms of the GNU General Public - * License version 2, as published by the Free Software Foundation, and - * may be copied, distributed, and modified under those terms. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - */ - -#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt - -#include <linux/mman.h> -#include <linux/module.h> -#include <linux/sched.h> -#include <linux/slab.h> -#include <linux/uaccess.h> -#include <linux/vmalloc.h> - -/* - * Several 32-bit architectures support 64-bit {get,put}_user() calls. - * As there doesn't appear to be anything that can safely determine - * their capability at compile-time, we just have to opt-out certain archs. - */ -#if BITS_PER_LONG == 64 || (!(defined(CONFIG_ARM) && !defined(MMU)) && \ - !defined(CONFIG_M68K) && \ - !defined(CONFIG_MICROBLAZE) && \ - !defined(CONFIG_NIOS2) && \ - !defined(CONFIG_PPC32) && \ - !defined(CONFIG_SUPERH)) -# define TEST_U64 -#endif - -#define test(condition, msg) \ -({ \ - int cond = (condition); \ - if (cond) \ - pr_warn("%s\n", msg); \ - cond; \ -}) - -static int __init test_user_copy_init(void) -{ - int ret = 0; - char *kmem; - char __user *usermem; - char *bad_usermem; - unsigned long user_addr; - u8 val_u8; - u16 val_u16; - u32 val_u32; -#ifdef TEST_U64 - u64 val_u64; -#endif - - kmem = kmalloc(PAGE_SIZE * 2, GFP_KERNEL); - if (!kmem) - return -ENOMEM; - - user_addr = vm_mmap(NULL, 0, PAGE_SIZE * 2, - PROT_READ | PROT_WRITE | PROT_EXEC, - MAP_ANONYMOUS | MAP_PRIVATE, 0); - if (user_addr >= (unsigned long)(TASK_SIZE)) { - pr_warn("Failed to allocate user memory\n"); - kfree(kmem); - return -ENOMEM; - } - - usermem = (char __user *)user_addr; - bad_usermem = (char *)user_addr; - - /* - * Legitimate usage: none of these copies should fail. - */ - memset(kmem, 0x3a, PAGE_SIZE * 2); - ret |= test(copy_to_user(usermem, kmem, PAGE_SIZE), - "legitimate copy_to_user failed"); - memset(kmem, 0x0, PAGE_SIZE); - ret |= test(copy_from_user(kmem, usermem, PAGE_SIZE), - "legitimate copy_from_user failed"); - ret |= test(memcmp(kmem, kmem + PAGE_SIZE, PAGE_SIZE), - "legitimate usercopy failed to copy data"); - -#define test_legit(size, check) \ - do { \ - val_##size = check; \ - ret |= test(put_user(val_##size, (size __user *)usermem), \ - "legitimate put_user (" #size ") failed"); \ - val_##size = 0; \ - ret |= test(get_user(val_##size, (size __user *)usermem), \ - "legitimate get_user (" #size ") failed"); \ - ret |= test(val_##size != check, \ - "legitimate get_user (" #size ") failed to do copy"); \ - if (val_##size != check) { \ - pr_info("0x%llx != 0x%llx\n", \ - (unsigned long long)val_##size, \ - (unsigned long long)check); \ - } \ - } while (0) - - test_legit(u8, 0x5a); - test_legit(u16, 0x5a5b); - test_legit(u32, 0x5a5b5c5d); -#ifdef TEST_U64 - test_legit(u64, 0x5a5b5c5d6a6b6c6d); -#endif -#undef test_legit - - /* - * Invalid usage: none of these copies should succeed. - */ - - /* Prepare kernel memory with check values. */ - memset(kmem, 0x5a, PAGE_SIZE); - memset(kmem + PAGE_SIZE, 0, PAGE_SIZE); - - /* Reject kernel-to-kernel copies through copy_from_user(). */ - ret |= test(!copy_from_user(kmem, (char __user *)(kmem + PAGE_SIZE), - PAGE_SIZE), - "illegal all-kernel copy_from_user passed"); - - /* Destination half of buffer should have been zeroed. */ - ret |= test(memcmp(kmem + PAGE_SIZE, kmem, PAGE_SIZE), - "zeroing failure for illegal all-kernel copy_from_user"); - -#if 0 - /* - * When running with SMAP/PAN/etc, this will Oops the kernel - * due to the zeroing of userspace memory on failure. This needs - * to be tested in LKDTM instead, since this test module does not - * expect to explode. - */ - ret |= test(!copy_from_user(bad_usermem, (char __user *)kmem, - PAGE_SIZE), - "illegal reversed copy_from_user passed"); -#endif - ret |= test(!copy_to_user((char __user *)kmem, kmem + PAGE_SIZE, - PAGE_SIZE), - "illegal all-kernel copy_to_user passed"); - ret |= test(!copy_to_user((char __user *)kmem, bad_usermem, - PAGE_SIZE), - "illegal reversed copy_to_user passed"); - -#define test_illegal(size, check) \ - do { \ - val_##size = (check); \ - ret |= test(!get_user(val_##size, (size __user *)kmem), \ - "illegal get_user (" #size ") passed"); \ - ret |= test(val_##size != (size)0, \ - "zeroing failure for illegal get_user (" #size ")"); \ - if (val_##size != (size)0) { \ - pr_info("0x%llx != 0\n", \ - (unsigned long long)val_##size); \ - } \ - ret |= test(!put_user(val_##size, (size __user *)kmem), \ - "illegal put_user (" #size ") passed"); \ - } while (0) - - test_illegal(u8, 0x5a); - test_illegal(u16, 0x5a5b); - test_illegal(u32, 0x5a5b5c5d); -#ifdef TEST_U64 - test_illegal(u64, 0x5a5b5c5d6a6b6c6d); -#endif -#undef test_illegal - - vm_munmap(user_addr, PAGE_SIZE * 2); - kfree(kmem); - - if (ret == 0) { - pr_info("tests passed.\n"); - return 0; - } - - return -EINVAL; -} - -module_init(test_user_copy_init); - -static void __exit test_user_copy_exit(void) -{ - pr_info("unloaded.\n"); -} - -module_exit(test_user_copy_exit); - -MODULE_AUTHOR("Kees Cook <keescook@chromium.org>"); -MODULE_LICENSE("GPL"); |