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-rw-r--r--lib/test_user_copy.c331
1 files changed, 0 insertions, 331 deletions
diff --git a/lib/test_user_copy.c b/lib/test_user_copy.c
deleted file mode 100644
index 5ff04d8fe971..000000000000
--- a/lib/test_user_copy.c
+++ /dev/null
@@ -1,331 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Kernel module for testing copy_to/from_user infrastructure.
- *
- * Copyright 2013 Google Inc. All Rights Reserved
- *
- * Authors:
- * Kees Cook <keescook@chromium.org>
- */
-
-#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("[%d] " msg "\n", __LINE__, ##__VA_ARGS__); \
- cond; \
-})
-
-static bool is_zeroed(void *from, size_t size)
-{
- return memchr_inv(from, 0x0, size) == NULL;
-}
-
-static int test_check_nonzero_user(char *kmem, char __user *umem, size_t size)
-{
- int ret = 0;
- size_t start, end, i, zero_start, zero_end;
-
- if (test(size < 2 * PAGE_SIZE, "buffer too small"))
- return -EINVAL;
-
- /*
- * We want to cross a page boundary to exercise the code more
- * effectively. We also don't want to make the size we scan too large,
- * otherwise the test can take a long time and cause soft lockups. So
- * scan a 1024 byte region across the page boundary.
- */
- size = 1024;
- start = PAGE_SIZE - (size / 2);
-
- kmem += start;
- umem += start;
-
- zero_start = size / 4;
- zero_end = size - zero_start;
-
- /*
- * We conduct a series of check_nonzero_user() tests on a block of
- * memory with the following byte-pattern (trying every possible
- * [start,end] pair):
- *
- * [ 00 ff 00 ff ... 00 00 00 00 ... ff 00 ff 00 ]
- *
- * And we verify that check_nonzero_user() acts identically to
- * memchr_inv().
- */
-
- memset(kmem, 0x0, size);
- for (i = 1; i < zero_start; i += 2)
- kmem[i] = 0xff;
- for (i = zero_end; i < size; i += 2)
- kmem[i] = 0xff;
-
- ret |= test(copy_to_user(umem, kmem, size),
- "legitimate copy_to_user failed");
-
- for (start = 0; start <= size; start++) {
- for (end = start; end <= size; end++) {
- size_t len = end - start;
- int retval = check_zeroed_user(umem + start, len);
- int expected = is_zeroed(kmem + start, len);
-
- ret |= test(retval != expected,
- "check_nonzero_user(=%d) != memchr_inv(=%d) mismatch (start=%zu, end=%zu)",
- retval, expected, start, end);
- }
- }
-
- return ret;
-}
-
-static int test_copy_struct_from_user(char *kmem, char __user *umem,
- size_t size)
-{
- int ret = 0;
- char *umem_src = NULL, *expected = NULL;
- size_t ksize, usize;
-
- umem_src = kmalloc(size, GFP_KERNEL);
- ret = test(umem_src == NULL, "kmalloc failed");
- if (ret)
- goto out_free;
-
- expected = kmalloc(size, GFP_KERNEL);
- ret = test(expected == NULL, "kmalloc failed");
- if (ret)
- goto out_free;
-
- /* Fill umem with a fixed byte pattern. */
- memset(umem_src, 0x3e, size);
- ret |= test(copy_to_user(umem, umem_src, size),
- "legitimate copy_to_user failed");
-
- /* Check basic case -- (usize == ksize). */
- ksize = size;
- usize = size;
-
- memcpy(expected, umem_src, ksize);
-
- memset(kmem, 0x0, size);
- ret |= test(copy_struct_from_user(kmem, ksize, umem, usize),
- "copy_struct_from_user(usize == ksize) failed");
- ret |= test(memcmp(kmem, expected, ksize),
- "copy_struct_from_user(usize == ksize) gives unexpected copy");
-
- /* Old userspace case -- (usize < ksize). */
- ksize = size;
- usize = size / 2;
-
- memcpy(expected, umem_src, usize);
- memset(expected + usize, 0x0, ksize - usize);
-
- memset(kmem, 0x0, size);
- ret |= test(copy_struct_from_user(kmem, ksize, umem, usize),
- "copy_struct_from_user(usize < ksize) failed");
- ret |= test(memcmp(kmem, expected, ksize),
- "copy_struct_from_user(usize < ksize) gives unexpected copy");
-
- /* New userspace (-E2BIG) case -- (usize > ksize). */
- ksize = size / 2;
- usize = size;
-
- memset(kmem, 0x0, size);
- ret |= test(copy_struct_from_user(kmem, ksize, umem, usize) != -E2BIG,
- "copy_struct_from_user(usize > ksize) didn't give E2BIG");
-
- /* New userspace (success) case -- (usize > ksize). */
- ksize = size / 2;
- usize = size;
-
- memcpy(expected, umem_src, ksize);
- ret |= test(clear_user(umem + ksize, usize - ksize),
- "legitimate clear_user failed");
-
- memset(kmem, 0x0, size);
- ret |= test(copy_struct_from_user(kmem, ksize, umem, usize),
- "copy_struct_from_user(usize > ksize) failed");
- ret |= test(memcmp(kmem, expected, ksize),
- "copy_struct_from_user(usize > ksize) gives unexpected copy");
-
-out_free:
- kfree(expected);
- kfree(umem_src);
- return ret;
-}
-
-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
-
- /* Test usage of check_nonzero_user(). */
- ret |= test_check_nonzero_user(kmem, usermem, 2 * PAGE_SIZE);
- /* Test usage of copy_struct_from_user(). */
- ret |= test_copy_struct_from_user(kmem, usermem, 2 * PAGE_SIZE);
-
- /*
- * 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");
generated by cgit v1.2.3-58-ga151 (git 2.39.0) at 2024-11-21 12:34:55 +0000