mirror of
https://github.com/torvalds/linux.git
synced 2024-11-10 14:11:52 +00:00
b6f5ee4d53
Move the exec KUnit tests into a separate directory to avoid polluting the local directory namespace. Additionally update MAINTAINERS for the new files. Reviewed-by: David Gow <davidgow@google.com> Reviewed-by: SeongJae Park <sj@kernel.org> Acked-by: Christian Brauner <brauner@kernel.org> Link: https://lore.kernel.org/r/20240720170310.it.942-kees@kernel.org Signed-off-by: Kees Cook <kees@kernel.org>
142 lines
6.5 KiB
C
142 lines
6.5 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
#include <kunit/test.h>
|
|
|
|
struct bprm_stack_limits_result {
|
|
struct linux_binprm bprm;
|
|
int expected_rc;
|
|
unsigned long expected_argmin;
|
|
};
|
|
|
|
static const struct bprm_stack_limits_result bprm_stack_limits_results[] = {
|
|
/* Negative argc/envc counts produce -E2BIG */
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = ULONG_MAX,
|
|
.argc = INT_MIN, .envc = INT_MIN }, .expected_rc = -E2BIG },
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = ULONG_MAX,
|
|
.argc = 5, .envc = -1 }, .expected_rc = -E2BIG },
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = ULONG_MAX,
|
|
.argc = -1, .envc = 10 }, .expected_rc = -E2BIG },
|
|
/* The max value of argc or envc is MAX_ARG_STRINGS. */
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = ULONG_MAX,
|
|
.argc = INT_MAX, .envc = INT_MAX }, .expected_rc = -E2BIG },
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = ULONG_MAX,
|
|
.argc = MAX_ARG_STRINGS, .envc = MAX_ARG_STRINGS }, .expected_rc = -E2BIG },
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = ULONG_MAX,
|
|
.argc = 0, .envc = MAX_ARG_STRINGS }, .expected_rc = -E2BIG },
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = ULONG_MAX,
|
|
.argc = MAX_ARG_STRINGS, .envc = 0 }, .expected_rc = -E2BIG },
|
|
/*
|
|
* On 32-bit system these argc and envc counts, while likely impossible
|
|
* to represent within the associated TASK_SIZE, could overflow the
|
|
* limit calculation, and bypass the ptr_size <= limit check.
|
|
*/
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = ULONG_MAX,
|
|
.argc = 0x20000001, .envc = 0x20000001 }, .expected_rc = -E2BIG },
|
|
#ifdef CONFIG_MMU
|
|
/* Make sure a pathological bprm->p doesn't cause an overflow. */
|
|
{ { .p = sizeof(void *), .rlim_stack.rlim_cur = ULONG_MAX,
|
|
.argc = 10, .envc = 10 }, .expected_rc = -E2BIG },
|
|
#endif
|
|
/*
|
|
* 0 rlim_stack will get raised to ARG_MAX. With 1 string pointer,
|
|
* we should see p - ARG_MAX + sizeof(void *).
|
|
*/
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = 0,
|
|
.argc = 1, .envc = 0 }, .expected_argmin = ULONG_MAX - ARG_MAX + sizeof(void *)},
|
|
/* Validate that argc is always raised to a minimum of 1. */
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = 0,
|
|
.argc = 0, .envc = 0 }, .expected_argmin = ULONG_MAX - ARG_MAX + sizeof(void *)},
|
|
/*
|
|
* 0 rlim_stack will get raised to ARG_MAX. With pointers filling ARG_MAX,
|
|
* we should see -E2BIG. (Note argc is always raised to at least 1.)
|
|
*/
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = 0,
|
|
.argc = ARG_MAX / sizeof(void *), .envc = 0 }, .expected_rc = -E2BIG },
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = 0,
|
|
.argc = 0, .envc = ARG_MAX / sizeof(void *) - 1 }, .expected_rc = -E2BIG },
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = 0,
|
|
.argc = ARG_MAX / sizeof(void *) + 1, .envc = 0 }, .expected_rc = -E2BIG },
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = 0,
|
|
.argc = 0, .envc = ARG_MAX / sizeof(void *) }, .expected_rc = -E2BIG },
|
|
/* And with one less, we see space for exactly 1 pointer. */
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = 0,
|
|
.argc = (ARG_MAX / sizeof(void *)) - 1, .envc = 0 },
|
|
.expected_argmin = ULONG_MAX - sizeof(void *) },
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = 0,
|
|
.argc = 0, .envc = (ARG_MAX / sizeof(void *)) - 2, },
|
|
.expected_argmin = ULONG_MAX - sizeof(void *) },
|
|
/* If we raise rlim_stack / 4 to exactly ARG_MAX, nothing changes. */
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = ARG_MAX * 4,
|
|
.argc = ARG_MAX / sizeof(void *), .envc = 0 }, .expected_rc = -E2BIG },
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = ARG_MAX * 4,
|
|
.argc = 0, .envc = ARG_MAX / sizeof(void *) - 1 }, .expected_rc = -E2BIG },
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = ARG_MAX * 4,
|
|
.argc = ARG_MAX / sizeof(void *) + 1, .envc = 0 }, .expected_rc = -E2BIG },
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = ARG_MAX * 4,
|
|
.argc = 0, .envc = ARG_MAX / sizeof(void *) }, .expected_rc = -E2BIG },
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = ARG_MAX * 4,
|
|
.argc = (ARG_MAX / sizeof(void *)) - 1, .envc = 0 },
|
|
.expected_argmin = ULONG_MAX - sizeof(void *) },
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = ARG_MAX * 4,
|
|
.argc = 0, .envc = (ARG_MAX / sizeof(void *)) - 2, },
|
|
.expected_argmin = ULONG_MAX - sizeof(void *) },
|
|
/* But raising it another pointer * 4 will provide space for 1 more pointer. */
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = (ARG_MAX + sizeof(void *)) * 4,
|
|
.argc = ARG_MAX / sizeof(void *), .envc = 0 },
|
|
.expected_argmin = ULONG_MAX - sizeof(void *) },
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = (ARG_MAX + sizeof(void *)) * 4,
|
|
.argc = 0, .envc = ARG_MAX / sizeof(void *) - 1 },
|
|
.expected_argmin = ULONG_MAX - sizeof(void *) },
|
|
/* Raising rlim_stack / 4 to _STK_LIM / 4 * 3 will see more space. */
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = 4 * (_STK_LIM / 4 * 3),
|
|
.argc = 0, .envc = 0 },
|
|
.expected_argmin = ULONG_MAX - (_STK_LIM / 4 * 3) + sizeof(void *) },
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = 4 * (_STK_LIM / 4 * 3),
|
|
.argc = 0, .envc = 0 },
|
|
.expected_argmin = ULONG_MAX - (_STK_LIM / 4 * 3) + sizeof(void *) },
|
|
/* But raising it any further will see no increase. */
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = 4 * (_STK_LIM / 4 * 3 + sizeof(void *)),
|
|
.argc = 0, .envc = 0 },
|
|
.expected_argmin = ULONG_MAX - (_STK_LIM / 4 * 3) + sizeof(void *) },
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = 4 * (_STK_LIM / 4 * + sizeof(void *)),
|
|
.argc = 0, .envc = 0 },
|
|
.expected_argmin = ULONG_MAX - (_STK_LIM / 4 * 3) + sizeof(void *) },
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = 4 * _STK_LIM,
|
|
.argc = 0, .envc = 0 },
|
|
.expected_argmin = ULONG_MAX - (_STK_LIM / 4 * 3) + sizeof(void *) },
|
|
{ { .p = ULONG_MAX, .rlim_stack.rlim_cur = 4 * _STK_LIM,
|
|
.argc = 0, .envc = 0 },
|
|
.expected_argmin = ULONG_MAX - (_STK_LIM / 4 * 3) + sizeof(void *) },
|
|
};
|
|
|
|
static void exec_test_bprm_stack_limits(struct kunit *test)
|
|
{
|
|
/* Double-check the constants. */
|
|
KUNIT_EXPECT_EQ(test, _STK_LIM, SZ_8M);
|
|
KUNIT_EXPECT_EQ(test, ARG_MAX, 32 * SZ_4K);
|
|
KUNIT_EXPECT_EQ(test, MAX_ARG_STRINGS, 0x7FFFFFFF);
|
|
|
|
for (int i = 0; i < ARRAY_SIZE(bprm_stack_limits_results); i++) {
|
|
const struct bprm_stack_limits_result *result = &bprm_stack_limits_results[i];
|
|
struct linux_binprm bprm = result->bprm;
|
|
int rc;
|
|
|
|
rc = bprm_stack_limits(&bprm);
|
|
KUNIT_EXPECT_EQ_MSG(test, rc, result->expected_rc, "on loop %d", i);
|
|
#ifdef CONFIG_MMU
|
|
KUNIT_EXPECT_EQ_MSG(test, bprm.argmin, result->expected_argmin, "on loop %d", i);
|
|
#endif
|
|
}
|
|
}
|
|
|
|
static struct kunit_case exec_test_cases[] = {
|
|
KUNIT_CASE(exec_test_bprm_stack_limits),
|
|
{},
|
|
};
|
|
|
|
static struct kunit_suite exec_test_suite = {
|
|
.name = "exec",
|
|
.test_cases = exec_test_cases,
|
|
};
|
|
|
|
kunit_test_suite(exec_test_suite);
|