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![Kees Cook](/assets/img/avatar_default.png)
When memcmp() returns a non-zero value, only the signed bit has any meaning. The actual value may differ between implementations. Reported-by: Nathan Chancellor <nathan@kernel.org> Closes: https://github.com/ClangBuiltLinux/linux/issues/2025 Tested-by: Nathan Chancellor <nathan@kernel.org> Link: https://lore.kernel.org/r/20240518184020.work.604-kees@kernel.org Signed-off-by: Kees Cook <keescook@chromium.org>
1103 lines
39 KiB
C
1103 lines
39 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Runtime test cases for CONFIG_FORTIFY_SOURCE. For additional memcpy()
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* testing see FORTIFY_MEM_* tests in LKDTM (drivers/misc/lkdtm/fortify.c).
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*
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* For corner cases with UBSAN, try testing with:
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*
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* ./tools/testing/kunit/kunit.py run --arch=x86_64 \
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* --kconfig_add CONFIG_FORTIFY_SOURCE=y \
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* --kconfig_add CONFIG_UBSAN=y \
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* --kconfig_add CONFIG_UBSAN_TRAP=y \
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* --kconfig_add CONFIG_UBSAN_BOUNDS=y \
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* --kconfig_add CONFIG_UBSAN_LOCAL_BOUNDS=y \
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* --make_options LLVM=1 fortify
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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/* We don't need to fill dmesg with the fortify WARNs during testing. */
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#ifdef DEBUG
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# define FORTIFY_REPORT_KUNIT(x...) __fortify_report(x)
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# define FORTIFY_WARN_KUNIT(x...) WARN_ONCE(x)
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#else
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# define FORTIFY_REPORT_KUNIT(x...) do { } while (0)
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# define FORTIFY_WARN_KUNIT(x...) do { } while (0)
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#endif
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/* Redefine fortify_panic() to track failures. */
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void fortify_add_kunit_error(int write);
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#define fortify_panic(func, write, avail, size, retfail) do { \
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FORTIFY_REPORT_KUNIT(FORTIFY_REASON(func, write), avail, size); \
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fortify_add_kunit_error(write); \
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return (retfail); \
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} while (0)
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/* Redefine fortify_warn_once() to track memcpy() failures. */
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#define fortify_warn_once(chk_func, x...) do { \
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bool __result = chk_func; \
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FORTIFY_WARN_KUNIT(__result, x); \
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if (__result) \
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fortify_add_kunit_error(1); \
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} while (0)
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#include <kunit/device.h>
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#include <kunit/test.h>
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#include <kunit/test-bug.h>
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#include <linux/device.h>
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#include <linux/slab.h>
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#include <linux/string.h>
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#include <linux/vmalloc.h>
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/* Handle being built without CONFIG_FORTIFY_SOURCE */
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#ifndef __compiletime_strlen
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# define __compiletime_strlen __builtin_strlen
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#endif
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static struct kunit_resource read_resource;
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static struct kunit_resource write_resource;
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static int fortify_read_overflows;
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static int fortify_write_overflows;
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static const char array_of_10[] = "this is 10";
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static const char *ptr_of_11 = "this is 11!";
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static char array_unknown[] = "compiler thinks I might change";
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void fortify_add_kunit_error(int write)
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{
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struct kunit_resource *resource;
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struct kunit *current_test;
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current_test = kunit_get_current_test();
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if (!current_test)
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return;
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resource = kunit_find_named_resource(current_test,
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write ? "fortify_write_overflows"
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: "fortify_read_overflows");
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if (!resource)
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return;
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(*(int *)resource->data)++;
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kunit_put_resource(resource);
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}
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static void fortify_test_known_sizes(struct kunit *test)
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{
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KUNIT_EXPECT_EQ(test, __compiletime_strlen("88888888"), 8);
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KUNIT_EXPECT_EQ(test, __compiletime_strlen(array_of_10), 10);
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KUNIT_EXPECT_EQ(test, __compiletime_strlen(ptr_of_11), 11);
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KUNIT_EXPECT_EQ(test, __compiletime_strlen(array_unknown), SIZE_MAX);
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/* Externally defined and dynamically sized string pointer: */
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KUNIT_EXPECT_EQ(test, __compiletime_strlen(test->name), SIZE_MAX);
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}
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/* This is volatile so the optimizer can't perform DCE below. */
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static volatile int pick;
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/* Not inline to keep optimizer from figuring out which string we want. */
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static noinline size_t want_minus_one(int pick)
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{
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const char *str;
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switch (pick) {
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case 1:
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str = "4444";
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break;
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case 2:
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str = "333";
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break;
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default:
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str = "1";
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break;
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}
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return __compiletime_strlen(str);
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}
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static void fortify_test_control_flow_split(struct kunit *test)
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{
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KUNIT_EXPECT_EQ(test, want_minus_one(pick), SIZE_MAX);
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}
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#define KUNIT_EXPECT_BOS(test, p, expected, name) \
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KUNIT_EXPECT_EQ_MSG(test, __builtin_object_size(p, 1), \
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expected, \
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"__alloc_size() not working with __bos on " name "\n")
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#if !__has_builtin(__builtin_dynamic_object_size)
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#define KUNIT_EXPECT_BDOS(test, p, expected, name) \
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/* Silence "unused variable 'expected'" warning. */ \
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KUNIT_EXPECT_EQ(test, expected, expected)
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#else
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#define KUNIT_EXPECT_BDOS(test, p, expected, name) \
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KUNIT_EXPECT_EQ_MSG(test, __builtin_dynamic_object_size(p, 1), \
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expected, \
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"__alloc_size() not working with __bdos on " name "\n")
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#endif
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/* If the execpted size is a constant value, __bos can see it. */
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#define check_const(_expected, alloc, free) do { \
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size_t expected = (_expected); \
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void *p = alloc; \
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KUNIT_EXPECT_TRUE_MSG(test, p != NULL, #alloc " failed?!\n"); \
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KUNIT_EXPECT_BOS(test, p, expected, #alloc); \
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KUNIT_EXPECT_BDOS(test, p, expected, #alloc); \
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free; \
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} while (0)
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/* If the execpted size is NOT a constant value, __bos CANNOT see it. */
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#define check_dynamic(_expected, alloc, free) do { \
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size_t expected = (_expected); \
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void *p = alloc; \
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KUNIT_EXPECT_TRUE_MSG(test, p != NULL, #alloc " failed?!\n"); \
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KUNIT_EXPECT_BOS(test, p, SIZE_MAX, #alloc); \
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KUNIT_EXPECT_BDOS(test, p, expected, #alloc); \
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free; \
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} while (0)
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/* Assortment of constant-value kinda-edge cases. */
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#define CONST_TEST_BODY(TEST_alloc) do { \
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/* Special-case vmalloc()-family to skip 0-sized allocs. */ \
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if (strcmp(#TEST_alloc, "TEST_vmalloc") != 0) \
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TEST_alloc(check_const, 0, 0); \
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TEST_alloc(check_const, 1, 1); \
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TEST_alloc(check_const, 128, 128); \
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TEST_alloc(check_const, 1023, 1023); \
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TEST_alloc(check_const, 1025, 1025); \
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TEST_alloc(check_const, 4096, 4096); \
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TEST_alloc(check_const, 4097, 4097); \
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} while (0)
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static volatile size_t zero_size;
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static volatile size_t unknown_size = 50;
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#if !__has_builtin(__builtin_dynamic_object_size)
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#define DYNAMIC_TEST_BODY(TEST_alloc) \
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kunit_skip(test, "Compiler is missing __builtin_dynamic_object_size() support\n")
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#else
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#define DYNAMIC_TEST_BODY(TEST_alloc) do { \
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size_t size = unknown_size; \
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\
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/* \
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* Expected size is "size" in each test, before it is then \
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* internally incremented in each test. Requires we disable \
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* -Wunsequenced. \
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*/ \
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TEST_alloc(check_dynamic, size, size++); \
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/* Make sure incrementing actually happened. */ \
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KUNIT_EXPECT_NE(test, size, unknown_size); \
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} while (0)
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#endif
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#define DEFINE_ALLOC_SIZE_TEST_PAIR(allocator) \
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static void fortify_test_alloc_size_##allocator##_const(struct kunit *test) \
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{ \
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CONST_TEST_BODY(TEST_##allocator); \
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} \
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static void fortify_test_alloc_size_##allocator##_dynamic(struct kunit *test) \
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{ \
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DYNAMIC_TEST_BODY(TEST_##allocator); \
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}
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#define TEST_kmalloc(checker, expected_size, alloc_size) do { \
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gfp_t gfp = GFP_KERNEL | __GFP_NOWARN; \
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void *orig; \
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size_t len; \
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\
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checker(expected_size, kmalloc(alloc_size, gfp), \
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kfree(p)); \
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checker(expected_size, \
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kmalloc_node(alloc_size, gfp, NUMA_NO_NODE), \
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kfree(p)); \
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checker(expected_size, kzalloc(alloc_size, gfp), \
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kfree(p)); \
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checker(expected_size, \
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kzalloc_node(alloc_size, gfp, NUMA_NO_NODE), \
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kfree(p)); \
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checker(expected_size, kcalloc(1, alloc_size, gfp), \
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kfree(p)); \
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checker(expected_size, kcalloc(alloc_size, 1, gfp), \
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kfree(p)); \
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checker(expected_size, \
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kcalloc_node(1, alloc_size, gfp, NUMA_NO_NODE), \
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kfree(p)); \
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checker(expected_size, \
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kcalloc_node(alloc_size, 1, gfp, NUMA_NO_NODE), \
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kfree(p)); \
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checker(expected_size, kmalloc_array(1, alloc_size, gfp), \
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kfree(p)); \
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checker(expected_size, kmalloc_array(alloc_size, 1, gfp), \
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kfree(p)); \
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checker(expected_size, \
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kmalloc_array_node(1, alloc_size, gfp, NUMA_NO_NODE), \
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kfree(p)); \
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checker(expected_size, \
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kmalloc_array_node(alloc_size, 1, gfp, NUMA_NO_NODE), \
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kfree(p)); \
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checker(expected_size, __kmalloc(alloc_size, gfp), \
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kfree(p)); \
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checker(expected_size, \
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__kmalloc_node(alloc_size, gfp, NUMA_NO_NODE), \
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kfree(p)); \
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\
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orig = kmalloc(alloc_size, gfp); \
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KUNIT_EXPECT_TRUE(test, orig != NULL); \
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checker((expected_size) * 2, \
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krealloc(orig, (alloc_size) * 2, gfp), \
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kfree(p)); \
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orig = kmalloc(alloc_size, gfp); \
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KUNIT_EXPECT_TRUE(test, orig != NULL); \
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checker((expected_size) * 2, \
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krealloc_array(orig, 1, (alloc_size) * 2, gfp), \
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kfree(p)); \
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orig = kmalloc(alloc_size, gfp); \
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KUNIT_EXPECT_TRUE(test, orig != NULL); \
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checker((expected_size) * 2, \
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krealloc_array(orig, (alloc_size) * 2, 1, gfp), \
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kfree(p)); \
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\
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len = 11; \
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/* Using memdup() with fixed size, so force unknown length. */ \
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if (!__builtin_constant_p(expected_size)) \
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len += zero_size; \
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checker(len, kmemdup("hello there", len, gfp), kfree(p)); \
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} while (0)
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DEFINE_ALLOC_SIZE_TEST_PAIR(kmalloc)
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/* Sizes are in pages, not bytes. */
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#define TEST_vmalloc(checker, expected_pages, alloc_pages) do { \
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gfp_t gfp = GFP_KERNEL | __GFP_NOWARN; \
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checker((expected_pages) * PAGE_SIZE, \
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vmalloc((alloc_pages) * PAGE_SIZE), vfree(p)); \
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checker((expected_pages) * PAGE_SIZE, \
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vzalloc((alloc_pages) * PAGE_SIZE), vfree(p)); \
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checker((expected_pages) * PAGE_SIZE, \
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__vmalloc((alloc_pages) * PAGE_SIZE, gfp), vfree(p)); \
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} while (0)
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DEFINE_ALLOC_SIZE_TEST_PAIR(vmalloc)
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/* Sizes are in pages (and open-coded for side-effects), not bytes. */
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#define TEST_kvmalloc(checker, expected_pages, alloc_pages) do { \
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gfp_t gfp = GFP_KERNEL | __GFP_NOWARN; \
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size_t prev_size; \
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void *orig; \
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\
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checker((expected_pages) * PAGE_SIZE, \
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kvmalloc((alloc_pages) * PAGE_SIZE, gfp), \
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kvfree(p)); \
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checker((expected_pages) * PAGE_SIZE, \
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kvmalloc_node((alloc_pages) * PAGE_SIZE, gfp, NUMA_NO_NODE), \
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kvfree(p)); \
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checker((expected_pages) * PAGE_SIZE, \
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kvzalloc((alloc_pages) * PAGE_SIZE, gfp), \
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kvfree(p)); \
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checker((expected_pages) * PAGE_SIZE, \
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kvzalloc_node((alloc_pages) * PAGE_SIZE, gfp, NUMA_NO_NODE), \
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kvfree(p)); \
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checker((expected_pages) * PAGE_SIZE, \
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kvcalloc(1, (alloc_pages) * PAGE_SIZE, gfp), \
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kvfree(p)); \
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checker((expected_pages) * PAGE_SIZE, \
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kvcalloc((alloc_pages) * PAGE_SIZE, 1, gfp), \
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kvfree(p)); \
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checker((expected_pages) * PAGE_SIZE, \
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kvmalloc_array(1, (alloc_pages) * PAGE_SIZE, gfp), \
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kvfree(p)); \
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checker((expected_pages) * PAGE_SIZE, \
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kvmalloc_array((alloc_pages) * PAGE_SIZE, 1, gfp), \
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kvfree(p)); \
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\
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prev_size = (expected_pages) * PAGE_SIZE; \
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orig = kvmalloc(prev_size, gfp); \
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KUNIT_EXPECT_TRUE(test, orig != NULL); \
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checker(((expected_pages) * PAGE_SIZE) * 2, \
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kvrealloc(orig, prev_size, \
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((alloc_pages) * PAGE_SIZE) * 2, gfp), \
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kvfree(p)); \
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} while (0)
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DEFINE_ALLOC_SIZE_TEST_PAIR(kvmalloc)
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#define TEST_devm_kmalloc(checker, expected_size, alloc_size) do { \
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gfp_t gfp = GFP_KERNEL | __GFP_NOWARN; \
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const char dev_name[] = "fortify-test"; \
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struct device *dev; \
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void *orig; \
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size_t len; \
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\
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/* Create dummy device for devm_kmalloc()-family tests. */ \
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dev = kunit_device_register(test, dev_name); \
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KUNIT_ASSERT_FALSE_MSG(test, IS_ERR(dev), \
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"Cannot register test device\n"); \
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\
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checker(expected_size, devm_kmalloc(dev, alloc_size, gfp), \
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devm_kfree(dev, p)); \
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checker(expected_size, devm_kzalloc(dev, alloc_size, gfp), \
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devm_kfree(dev, p)); \
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checker(expected_size, \
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devm_kmalloc_array(dev, 1, alloc_size, gfp), \
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devm_kfree(dev, p)); \
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checker(expected_size, \
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devm_kmalloc_array(dev, alloc_size, 1, gfp), \
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devm_kfree(dev, p)); \
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checker(expected_size, \
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devm_kcalloc(dev, 1, alloc_size, gfp), \
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devm_kfree(dev, p)); \
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checker(expected_size, \
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devm_kcalloc(dev, alloc_size, 1, gfp), \
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devm_kfree(dev, p)); \
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\
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orig = devm_kmalloc(dev, alloc_size, gfp); \
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KUNIT_EXPECT_TRUE(test, orig != NULL); \
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checker((expected_size) * 2, \
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devm_krealloc(dev, orig, (alloc_size) * 2, gfp), \
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devm_kfree(dev, p)); \
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\
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len = 4; \
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/* Using memdup() with fixed size, so force unknown length. */ \
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if (!__builtin_constant_p(expected_size)) \
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len += zero_size; \
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checker(len, devm_kmemdup(dev, "Ohai", len, gfp), \
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devm_kfree(dev, p)); \
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\
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kunit_device_unregister(test, dev); \
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} while (0)
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DEFINE_ALLOC_SIZE_TEST_PAIR(devm_kmalloc)
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static const char * const test_strs[] = {
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"",
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"Hello there",
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"A longer string, just for variety",
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};
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#define TEST_realloc(checker) do { \
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gfp_t gfp = GFP_KERNEL; \
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size_t len; \
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int i; \
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\
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for (i = 0; i < ARRAY_SIZE(test_strs); i++) { \
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len = strlen(test_strs[i]); \
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KUNIT_EXPECT_EQ(test, __builtin_constant_p(len), 0); \
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checker(len, kmemdup_array(test_strs[i], len, 1, gfp), \
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kfree(p)); \
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checker(len, kmemdup(test_strs[i], len, gfp), \
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kfree(p)); \
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} \
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} while (0)
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static void fortify_test_realloc_size(struct kunit *test)
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{
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TEST_realloc(check_dynamic);
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}
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/*
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* We can't have an array at the end of a structure or else
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* builds without -fstrict-flex-arrays=3 will report them as
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* being an unknown length. Additionally, add bytes before
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* and after the string to catch over/underflows if tests
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* fail.
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*/
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struct fortify_padding {
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unsigned long bytes_before;
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char buf[32];
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unsigned long bytes_after;
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};
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/* Force compiler into not being able to resolve size at compile-time. */
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static volatile int unconst;
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static void fortify_test_strlen(struct kunit *test)
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{
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struct fortify_padding pad = { };
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int i, end = sizeof(pad.buf) - 1;
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/* Fill 31 bytes with valid characters. */
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for (i = 0; i < sizeof(pad.buf) - 1; i++)
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pad.buf[i] = i + '0';
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/* Trailing bytes are still %NUL. */
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KUNIT_EXPECT_EQ(test, pad.buf[end], '\0');
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KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
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/* String is terminated, so strlen() is valid. */
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KUNIT_EXPECT_EQ(test, strlen(pad.buf), end);
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KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
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/* Make string unterminated, and recount. */
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pad.buf[end] = 'A';
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end = sizeof(pad.buf);
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KUNIT_EXPECT_EQ(test, strlen(pad.buf), end);
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KUNIT_EXPECT_EQ(test, fortify_read_overflows, 1);
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}
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static void fortify_test_strnlen(struct kunit *test)
|
|
{
|
|
struct fortify_padding pad = { };
|
|
int i, end = sizeof(pad.buf) - 1;
|
|
|
|
/* Fill 31 bytes with valid characters. */
|
|
for (i = 0; i < sizeof(pad.buf) - 1; i++)
|
|
pad.buf[i] = i + '0';
|
|
/* Trailing bytes are still %NUL. */
|
|
KUNIT_EXPECT_EQ(test, pad.buf[end], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
|
|
/* String is terminated, so strnlen() is valid. */
|
|
KUNIT_EXPECT_EQ(test, strnlen(pad.buf, sizeof(pad.buf)), end);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
|
|
/* A truncated strnlen() will be safe, too. */
|
|
KUNIT_EXPECT_EQ(test, strnlen(pad.buf, sizeof(pad.buf) / 2),
|
|
sizeof(pad.buf) / 2);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
|
|
|
|
/* Make string unterminated, and recount. */
|
|
pad.buf[end] = 'A';
|
|
end = sizeof(pad.buf);
|
|
/* Reading beyond with strncpy() will fail. */
|
|
KUNIT_EXPECT_EQ(test, strnlen(pad.buf, end + 1), end);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 1);
|
|
KUNIT_EXPECT_EQ(test, strnlen(pad.buf, end + 2), end);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 2);
|
|
|
|
/* Early-truncated is safe still, though. */
|
|
KUNIT_EXPECT_EQ(test, strnlen(pad.buf, end), end);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 2);
|
|
|
|
end = sizeof(pad.buf) / 2;
|
|
KUNIT_EXPECT_EQ(test, strnlen(pad.buf, end), end);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 2);
|
|
}
|
|
|
|
static void fortify_test_strcpy(struct kunit *test)
|
|
{
|
|
struct fortify_padding pad = { };
|
|
char src[sizeof(pad.buf) + 1] = { };
|
|
int i;
|
|
|
|
/* Fill 31 bytes with valid characters. */
|
|
for (i = 0; i < sizeof(src) - 2; i++)
|
|
src[i] = i + '0';
|
|
|
|
/* Destination is %NUL-filled to start with. */
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_before, 0);
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
|
|
/* Legitimate strcpy() 1 less than of max size. */
|
|
KUNIT_ASSERT_TRUE(test, strcpy(pad.buf, src)
|
|
== pad.buf);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 0);
|
|
/* Only last byte should be %NUL */
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
|
|
src[sizeof(src) - 2] = 'A';
|
|
/* But now we trip the overflow checking. */
|
|
KUNIT_ASSERT_TRUE(test, strcpy(pad.buf, src)
|
|
== pad.buf);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 1);
|
|
/* Trailing %NUL -- thanks to FORTIFY. */
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
/* And we will not have gone beyond. */
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
|
|
src[sizeof(src) - 1] = 'A';
|
|
/* And for sure now, two bytes past. */
|
|
KUNIT_ASSERT_TRUE(test, strcpy(pad.buf, src)
|
|
== pad.buf);
|
|
/*
|
|
* Which trips both the strlen() on the unterminated src,
|
|
* and the resulting copy attempt.
|
|
*/
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 1);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 2);
|
|
/* Trailing %NUL -- thanks to FORTIFY. */
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
/* And we will not have gone beyond. */
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
}
|
|
|
|
static void fortify_test_strncpy(struct kunit *test)
|
|
{
|
|
struct fortify_padding pad = { };
|
|
char src[] = "Copy me fully into a small buffer and I will overflow!";
|
|
|
|
/* Destination is %NUL-filled to start with. */
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_before, 0);
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
|
|
/* Legitimate strncpy() 1 less than of max size. */
|
|
KUNIT_ASSERT_TRUE(test, strncpy(pad.buf, src,
|
|
sizeof(pad.buf) + unconst - 1)
|
|
== pad.buf);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 0);
|
|
/* Only last byte should be %NUL */
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
|
|
/* Legitimate (though unterminated) max-size strncpy. */
|
|
KUNIT_ASSERT_TRUE(test, strncpy(pad.buf, src,
|
|
sizeof(pad.buf) + unconst)
|
|
== pad.buf);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 0);
|
|
/* No trailing %NUL -- thanks strncpy API. */
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
/* But we will not have gone beyond. */
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
|
|
/* Now verify that FORTIFY is working... */
|
|
KUNIT_ASSERT_TRUE(test, strncpy(pad.buf, src,
|
|
sizeof(pad.buf) + unconst + 1)
|
|
== pad.buf);
|
|
/* Should catch the overflow. */
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 1);
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
/* And we will not have gone beyond. */
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
|
|
/* And further... */
|
|
KUNIT_ASSERT_TRUE(test, strncpy(pad.buf, src,
|
|
sizeof(pad.buf) + unconst + 2)
|
|
== pad.buf);
|
|
/* Should catch the overflow. */
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 2);
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
/* And we will not have gone beyond. */
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
}
|
|
|
|
static void fortify_test_strscpy(struct kunit *test)
|
|
{
|
|
struct fortify_padding pad = { };
|
|
char src[] = "Copy me fully into a small buffer and I will overflow!";
|
|
|
|
/* Destination is %NUL-filled to start with. */
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_before, 0);
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
|
|
/* Legitimate strscpy() 1 less than of max size. */
|
|
KUNIT_ASSERT_EQ(test, strscpy(pad.buf, src,
|
|
sizeof(pad.buf) + unconst - 1),
|
|
-E2BIG);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 0);
|
|
/* Keeping space for %NUL, last two bytes should be %NUL */
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
|
|
/* Legitimate max-size strscpy. */
|
|
KUNIT_ASSERT_EQ(test, strscpy(pad.buf, src,
|
|
sizeof(pad.buf) + unconst),
|
|
-E2BIG);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 0);
|
|
/* A trailing %NUL will exist. */
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
|
|
/* Now verify that FORTIFY is working... */
|
|
KUNIT_ASSERT_EQ(test, strscpy(pad.buf, src,
|
|
sizeof(pad.buf) + unconst + 1),
|
|
-E2BIG);
|
|
/* Should catch the overflow. */
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 1);
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
/* And we will not have gone beyond. */
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
|
|
/* And much further... */
|
|
KUNIT_ASSERT_EQ(test, strscpy(pad.buf, src,
|
|
sizeof(src) * 2 + unconst),
|
|
-E2BIG);
|
|
/* Should catch the overflow. */
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 2);
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
/* And we will not have gone beyond. */
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
}
|
|
|
|
static void fortify_test_strcat(struct kunit *test)
|
|
{
|
|
struct fortify_padding pad = { };
|
|
char src[sizeof(pad.buf) / 2] = { };
|
|
char one[] = "A";
|
|
char two[] = "BC";
|
|
int i;
|
|
|
|
/* Fill 15 bytes with valid characters. */
|
|
for (i = 0; i < sizeof(src) - 1; i++)
|
|
src[i] = i + 'A';
|
|
|
|
/* Destination is %NUL-filled to start with. */
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_before, 0);
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
|
|
/* Legitimate strcat() using less than half max size. */
|
|
KUNIT_ASSERT_TRUE(test, strcat(pad.buf, src) == pad.buf);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 0);
|
|
/* Legitimate strcat() now 2 bytes shy of end. */
|
|
KUNIT_ASSERT_TRUE(test, strcat(pad.buf, src) == pad.buf);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 0);
|
|
/* Last two bytes should be %NUL */
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
|
|
/* Add one more character to the end. */
|
|
KUNIT_ASSERT_TRUE(test, strcat(pad.buf, one) == pad.buf);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 0);
|
|
/* Last byte should be %NUL */
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
|
|
/* And this one char will overflow. */
|
|
KUNIT_ASSERT_TRUE(test, strcat(pad.buf, one) == pad.buf);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 1);
|
|
/* Last byte should be %NUL thanks to FORTIFY. */
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
|
|
/* And adding two will overflow more. */
|
|
KUNIT_ASSERT_TRUE(test, strcat(pad.buf, two) == pad.buf);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 2);
|
|
/* Last byte should be %NUL thanks to FORTIFY. */
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
}
|
|
|
|
static void fortify_test_strncat(struct kunit *test)
|
|
{
|
|
struct fortify_padding pad = { };
|
|
char src[sizeof(pad.buf)] = { };
|
|
int i, partial;
|
|
|
|
/* Fill 31 bytes with valid characters. */
|
|
partial = sizeof(src) / 2 - 1;
|
|
for (i = 0; i < partial; i++)
|
|
src[i] = i + 'A';
|
|
|
|
/* Destination is %NUL-filled to start with. */
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_before, 0);
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
|
|
/* Legitimate strncat() using less than half max size. */
|
|
KUNIT_ASSERT_TRUE(test, strncat(pad.buf, src, partial) == pad.buf);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 0);
|
|
/* Legitimate strncat() now 2 bytes shy of end. */
|
|
KUNIT_ASSERT_TRUE(test, strncat(pad.buf, src, partial) == pad.buf);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 0);
|
|
/* Last two bytes should be %NUL */
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
|
|
/* Add one more character to the end. */
|
|
KUNIT_ASSERT_TRUE(test, strncat(pad.buf, src, 1) == pad.buf);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 0);
|
|
/* Last byte should be %NUL */
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
|
|
/* And this one char will overflow. */
|
|
KUNIT_ASSERT_TRUE(test, strncat(pad.buf, src, 1) == pad.buf);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 1);
|
|
/* Last byte should be %NUL thanks to FORTIFY. */
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
|
|
/* And adding two will overflow more. */
|
|
KUNIT_ASSERT_TRUE(test, strncat(pad.buf, src, 2) == pad.buf);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 2);
|
|
/* Last byte should be %NUL thanks to FORTIFY. */
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
|
|
/* Force an unterminated destination, and overflow. */
|
|
pad.buf[sizeof(pad.buf) - 1] = 'A';
|
|
KUNIT_ASSERT_TRUE(test, strncat(pad.buf, src, 1) == pad.buf);
|
|
/* This will have tripped both strlen() and strcat(). */
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 1);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 3);
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
/* But we should not go beyond the end. */
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
}
|
|
|
|
static void fortify_test_strlcat(struct kunit *test)
|
|
{
|
|
struct fortify_padding pad = { };
|
|
char src[sizeof(pad.buf)] = { };
|
|
int i, partial;
|
|
int len = sizeof(pad.buf) + unconst;
|
|
|
|
/* Fill 15 bytes with valid characters. */
|
|
partial = sizeof(src) / 2 - 1;
|
|
for (i = 0; i < partial; i++)
|
|
src[i] = i + 'A';
|
|
|
|
/* Destination is %NUL-filled to start with. */
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_before, 0);
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
|
|
/* Legitimate strlcat() using less than half max size. */
|
|
KUNIT_ASSERT_EQ(test, strlcat(pad.buf, src, len), partial);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 0);
|
|
/* Legitimate strlcat() now 2 bytes shy of end. */
|
|
KUNIT_ASSERT_EQ(test, strlcat(pad.buf, src, len), partial * 2);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 0);
|
|
/* Last two bytes should be %NUL */
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
|
|
/* Add one more character to the end. */
|
|
KUNIT_ASSERT_EQ(test, strlcat(pad.buf, "Q", len), partial * 2 + 1);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 0);
|
|
/* Last byte should be %NUL */
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
|
|
/* And this one char will overflow. */
|
|
KUNIT_ASSERT_EQ(test, strlcat(pad.buf, "V", len * 2), len);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 1);
|
|
/* Last byte should be %NUL thanks to FORTIFY. */
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
|
|
/* And adding two will overflow more. */
|
|
KUNIT_ASSERT_EQ(test, strlcat(pad.buf, "QQ", len * 2), len + 1);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 2);
|
|
/* Last byte should be %NUL thanks to FORTIFY. */
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
|
|
/* Force an unterminated destination, and overflow. */
|
|
pad.buf[sizeof(pad.buf) - 1] = 'A';
|
|
KUNIT_ASSERT_EQ(test, strlcat(pad.buf, "TT", len * 2), len + 2);
|
|
/* This will have tripped both strlen() and strlcat(). */
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 2);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 2);
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 2], '\0');
|
|
KUNIT_EXPECT_NE(test, pad.buf[sizeof(pad.buf) - 3], '\0');
|
|
/* But we should not go beyond the end. */
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
|
|
/* Force an unterminated source, and overflow. */
|
|
memset(src, 'B', sizeof(src));
|
|
pad.buf[sizeof(pad.buf) - 1] = '\0';
|
|
KUNIT_ASSERT_EQ(test, strlcat(pad.buf, src, len * 3), len - 1 + sizeof(src));
|
|
/* This will have tripped both strlen() and strlcat(). */
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 3);
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 3);
|
|
KUNIT_EXPECT_EQ(test, pad.buf[sizeof(pad.buf) - 1], '\0');
|
|
/* But we should not go beyond the end. */
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0);
|
|
}
|
|
|
|
/* Check for 0-sized arrays... */
|
|
struct fortify_zero_sized {
|
|
unsigned long bytes_before;
|
|
char buf[0];
|
|
unsigned long bytes_after;
|
|
};
|
|
|
|
#define __fortify_test(memfunc) \
|
|
static void fortify_test_##memfunc(struct kunit *test) \
|
|
{ \
|
|
struct fortify_zero_sized zero = { }; \
|
|
struct fortify_padding pad = { }; \
|
|
char srcA[sizeof(pad.buf) + 2]; \
|
|
char srcB[sizeof(pad.buf) + 2]; \
|
|
size_t len = sizeof(pad.buf) + unconst; \
|
|
\
|
|
memset(srcA, 'A', sizeof(srcA)); \
|
|
KUNIT_ASSERT_EQ(test, srcA[0], 'A'); \
|
|
memset(srcB, 'B', sizeof(srcB)); \
|
|
KUNIT_ASSERT_EQ(test, srcB[0], 'B'); \
|
|
\
|
|
memfunc(pad.buf, srcA, 0 + unconst); \
|
|
KUNIT_EXPECT_EQ(test, pad.buf[0], '\0'); \
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0); \
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 0); \
|
|
memfunc(pad.buf + 1, srcB, 1 + unconst); \
|
|
KUNIT_EXPECT_EQ(test, pad.buf[0], '\0'); \
|
|
KUNIT_EXPECT_EQ(test, pad.buf[1], 'B'); \
|
|
KUNIT_EXPECT_EQ(test, pad.buf[2], '\0'); \
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0); \
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 0); \
|
|
memfunc(pad.buf, srcA, 1 + unconst); \
|
|
KUNIT_EXPECT_EQ(test, pad.buf[0], 'A'); \
|
|
KUNIT_EXPECT_EQ(test, pad.buf[1], 'B'); \
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0); \
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 0); \
|
|
memfunc(pad.buf, srcA, len - 1); \
|
|
KUNIT_EXPECT_EQ(test, pad.buf[1], 'A'); \
|
|
KUNIT_EXPECT_EQ(test, pad.buf[len - 1], '\0'); \
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0); \
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 0); \
|
|
memfunc(pad.buf, srcA, len); \
|
|
KUNIT_EXPECT_EQ(test, pad.buf[1], 'A'); \
|
|
KUNIT_EXPECT_EQ(test, pad.buf[len - 1], 'A'); \
|
|
KUNIT_EXPECT_EQ(test, pad.bytes_after, 0); \
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0); \
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 0); \
|
|
memfunc(pad.buf, srcA, len + 1); \
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0); \
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 1); \
|
|
memfunc(pad.buf + 1, srcB, len); \
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0); \
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 2); \
|
|
\
|
|
/* Reset error counter. */ \
|
|
fortify_write_overflows = 0; \
|
|
/* Copy nothing into nothing: no errors. */ \
|
|
memfunc(zero.buf, srcB, 0 + unconst); \
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0); \
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 0); \
|
|
/* We currently explicitly ignore zero-sized dests. */ \
|
|
memfunc(zero.buf, srcB, 1 + unconst); \
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0); \
|
|
KUNIT_EXPECT_EQ(test, fortify_write_overflows, 0); \
|
|
}
|
|
__fortify_test(memcpy)
|
|
__fortify_test(memmove)
|
|
|
|
static void fortify_test_memscan(struct kunit *test)
|
|
{
|
|
char haystack[] = "Where oh where is my memory range?";
|
|
char *mem = haystack + strlen("Where oh where is ");
|
|
char needle = 'm';
|
|
size_t len = sizeof(haystack) + unconst;
|
|
|
|
KUNIT_ASSERT_PTR_EQ(test, memscan(haystack, needle, len),
|
|
mem);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
|
|
/* Catch too-large range. */
|
|
KUNIT_ASSERT_PTR_EQ(test, memscan(haystack, needle, len + 1),
|
|
NULL);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 1);
|
|
KUNIT_ASSERT_PTR_EQ(test, memscan(haystack, needle, len * 2),
|
|
NULL);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 2);
|
|
}
|
|
|
|
static void fortify_test_memchr(struct kunit *test)
|
|
{
|
|
char haystack[] = "Where oh where is my memory range?";
|
|
char *mem = haystack + strlen("Where oh where is ");
|
|
char needle = 'm';
|
|
size_t len = sizeof(haystack) + unconst;
|
|
|
|
KUNIT_ASSERT_PTR_EQ(test, memchr(haystack, needle, len),
|
|
mem);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
|
|
/* Catch too-large range. */
|
|
KUNIT_ASSERT_PTR_EQ(test, memchr(haystack, needle, len + 1),
|
|
NULL);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 1);
|
|
KUNIT_ASSERT_PTR_EQ(test, memchr(haystack, needle, len * 2),
|
|
NULL);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 2);
|
|
}
|
|
|
|
static void fortify_test_memchr_inv(struct kunit *test)
|
|
{
|
|
char haystack[] = "Where oh where is my memory range?";
|
|
char *mem = haystack + 1;
|
|
char needle = 'W';
|
|
size_t len = sizeof(haystack) + unconst;
|
|
|
|
/* Normal search is okay. */
|
|
KUNIT_ASSERT_PTR_EQ(test, memchr_inv(haystack, needle, len),
|
|
mem);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
|
|
/* Catch too-large range. */
|
|
KUNIT_ASSERT_PTR_EQ(test, memchr_inv(haystack, needle, len + 1),
|
|
NULL);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 1);
|
|
KUNIT_ASSERT_PTR_EQ(test, memchr_inv(haystack, needle, len * 2),
|
|
NULL);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 2);
|
|
}
|
|
|
|
static void fortify_test_memcmp(struct kunit *test)
|
|
{
|
|
char one[] = "My mind is going ...";
|
|
char two[] = "My mind is going ... I can feel it.";
|
|
size_t one_len = sizeof(one) + unconst - 1;
|
|
size_t two_len = sizeof(two) + unconst - 1;
|
|
|
|
/* We match the first string (ignoring the %NUL). */
|
|
KUNIT_ASSERT_EQ(test, memcmp(one, two, one_len), 0);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
|
|
/* Still in bounds, but no longer matching. */
|
|
KUNIT_ASSERT_LT(test, memcmp(one, two, one_len + 1), 0);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
|
|
|
|
/* Catch too-large ranges. */
|
|
KUNIT_ASSERT_EQ(test, memcmp(one, two, one_len + 2), INT_MIN);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 1);
|
|
|
|
KUNIT_ASSERT_EQ(test, memcmp(two, one, two_len + 2), INT_MIN);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 2);
|
|
}
|
|
|
|
static void fortify_test_kmemdup(struct kunit *test)
|
|
{
|
|
char src[] = "I got Doom running on it!";
|
|
char *copy;
|
|
size_t len = sizeof(src) + unconst;
|
|
|
|
/* Copy is within bounds. */
|
|
copy = kmemdup(src, len, GFP_KERNEL);
|
|
KUNIT_EXPECT_NOT_NULL(test, copy);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
|
|
kfree(copy);
|
|
|
|
/* Without %NUL. */
|
|
copy = kmemdup(src, len - 1, GFP_KERNEL);
|
|
KUNIT_EXPECT_NOT_NULL(test, copy);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
|
|
kfree(copy);
|
|
|
|
/* Tiny bounds. */
|
|
copy = kmemdup(src, 1, GFP_KERNEL);
|
|
KUNIT_EXPECT_NOT_NULL(test, copy);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
|
|
kfree(copy);
|
|
|
|
/* Out of bounds by 1 byte. */
|
|
copy = kmemdup(src, len + 1, GFP_KERNEL);
|
|
KUNIT_EXPECT_PTR_EQ(test, copy, ZERO_SIZE_PTR);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 1);
|
|
kfree(copy);
|
|
|
|
/* Way out of bounds. */
|
|
copy = kmemdup(src, len * 2, GFP_KERNEL);
|
|
KUNIT_EXPECT_PTR_EQ(test, copy, ZERO_SIZE_PTR);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 2);
|
|
kfree(copy);
|
|
|
|
/* Starting offset causing out of bounds. */
|
|
copy = kmemdup(src + 1, len, GFP_KERNEL);
|
|
KUNIT_EXPECT_PTR_EQ(test, copy, ZERO_SIZE_PTR);
|
|
KUNIT_EXPECT_EQ(test, fortify_read_overflows, 3);
|
|
kfree(copy);
|
|
}
|
|
|
|
static int fortify_test_init(struct kunit *test)
|
|
{
|
|
if (!IS_ENABLED(CONFIG_FORTIFY_SOURCE))
|
|
kunit_skip(test, "Not built with CONFIG_FORTIFY_SOURCE=y");
|
|
|
|
fortify_read_overflows = 0;
|
|
kunit_add_named_resource(test, NULL, NULL, &read_resource,
|
|
"fortify_read_overflows",
|
|
&fortify_read_overflows);
|
|
fortify_write_overflows = 0;
|
|
kunit_add_named_resource(test, NULL, NULL, &write_resource,
|
|
"fortify_write_overflows",
|
|
&fortify_write_overflows);
|
|
return 0;
|
|
}
|
|
|
|
static struct kunit_case fortify_test_cases[] = {
|
|
KUNIT_CASE(fortify_test_known_sizes),
|
|
KUNIT_CASE(fortify_test_control_flow_split),
|
|
KUNIT_CASE(fortify_test_alloc_size_kmalloc_const),
|
|
KUNIT_CASE(fortify_test_alloc_size_kmalloc_dynamic),
|
|
KUNIT_CASE(fortify_test_alloc_size_vmalloc_const),
|
|
KUNIT_CASE(fortify_test_alloc_size_vmalloc_dynamic),
|
|
KUNIT_CASE(fortify_test_alloc_size_kvmalloc_const),
|
|
KUNIT_CASE(fortify_test_alloc_size_kvmalloc_dynamic),
|
|
KUNIT_CASE(fortify_test_alloc_size_devm_kmalloc_const),
|
|
KUNIT_CASE(fortify_test_alloc_size_devm_kmalloc_dynamic),
|
|
KUNIT_CASE(fortify_test_realloc_size),
|
|
KUNIT_CASE(fortify_test_strlen),
|
|
KUNIT_CASE(fortify_test_strnlen),
|
|
KUNIT_CASE(fortify_test_strcpy),
|
|
KUNIT_CASE(fortify_test_strncpy),
|
|
KUNIT_CASE(fortify_test_strscpy),
|
|
KUNIT_CASE(fortify_test_strcat),
|
|
KUNIT_CASE(fortify_test_strncat),
|
|
KUNIT_CASE(fortify_test_strlcat),
|
|
/* skip memset: performs bounds checking on whole structs */
|
|
KUNIT_CASE(fortify_test_memcpy),
|
|
KUNIT_CASE(fortify_test_memmove),
|
|
KUNIT_CASE(fortify_test_memscan),
|
|
KUNIT_CASE(fortify_test_memchr),
|
|
KUNIT_CASE(fortify_test_memchr_inv),
|
|
KUNIT_CASE(fortify_test_memcmp),
|
|
KUNIT_CASE(fortify_test_kmemdup),
|
|
{}
|
|
};
|
|
|
|
static struct kunit_suite fortify_test_suite = {
|
|
.name = "fortify",
|
|
.init = fortify_test_init,
|
|
.test_cases = fortify_test_cases,
|
|
};
|
|
|
|
kunit_test_suite(fortify_test_suite);
|
|
|
|
MODULE_LICENSE("GPL");
|