linux/lib/kunit/executor.c
Daniel Latypov cd94fbc2ca kunit: fix too small allocation when using suite-only kunit.filter_glob
When a user filters by a suite and not a test, e.g.
$ ./tools/testing/kunit/kunit.py run 'suite_name'

it hits this code
  const int len = strlen(filter_glob);
  ...
  parsed->suite_glob = kmalloc(len, GFP_KERNEL);
which fails to allocate space for the terminating NULL.

Somehow, it seems like we can't easily reproduce this under UML, so the
existing `parse_filter_test()` didn't catch this.

Fix this by allocating `len + 1` and switch to kzalloc() just to be a
bit more defensive. We're only going to run this code once per kernel
boot, and it should never be very long.

Also update the unit tests to be a bit more cautious.
This bug showed up as a NULL pointer dereference here:
>  KUNIT_EXPECT_STREQ(test, (const char *)filtered.start[0][0]->name, "suite0");
`filtered.start[0][0]` was NULL, and `name` is at offset 0 in the struct,
so `...->name` was also NULL.

Fixes: 3b29021ddd10 ("kunit: tool: allow filtering test cases via glob")
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Acked-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2021-10-19 14:18:49 -06:00

229 lines
5.7 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/reboot.h>
#include <kunit/test.h>
#include <linux/glob.h>
#include <linux/moduleparam.h>
/*
* These symbols point to the .kunit_test_suites section and are defined in
* include/asm-generic/vmlinux.lds.h, and consequently must be extern.
*/
extern struct kunit_suite * const * const __kunit_suites_start[];
extern struct kunit_suite * const * const __kunit_suites_end[];
#if IS_BUILTIN(CONFIG_KUNIT)
static char *filter_glob_param;
module_param_named(filter_glob, filter_glob_param, charp, 0);
MODULE_PARM_DESC(filter_glob,
"Filter which KUnit test suites/tests run at boot-time, e.g. list* or list*.*del_test");
/* glob_match() needs NULL terminated strings, so we need a copy of filter_glob_param. */
struct kunit_test_filter {
char *suite_glob;
char *test_glob;
};
/* Split "suite_glob.test_glob" into two. Assumes filter_glob is not empty. */
static void kunit_parse_filter_glob(struct kunit_test_filter *parsed,
const char *filter_glob)
{
const int len = strlen(filter_glob);
const char *period = strchr(filter_glob, '.');
if (!period) {
parsed->suite_glob = kzalloc(len + 1, GFP_KERNEL);
parsed->test_glob = NULL;
strcpy(parsed->suite_glob, filter_glob);
return;
}
parsed->suite_glob = kzalloc(period - filter_glob + 1, GFP_KERNEL);
parsed->test_glob = kzalloc(len - (period - filter_glob) + 1, GFP_KERNEL);
strncpy(parsed->suite_glob, filter_glob, period - filter_glob);
strncpy(parsed->test_glob, period + 1, len - (period - filter_glob));
}
/* Create a copy of suite with only tests that match test_glob. */
static struct kunit_suite *
kunit_filter_tests(struct kunit_suite *const suite, const char *test_glob)
{
int n = 0;
struct kunit_case *filtered, *test_case;
struct kunit_suite *copy;
kunit_suite_for_each_test_case(suite, test_case) {
if (!test_glob || glob_match(test_glob, test_case->name))
++n;
}
if (n == 0)
return NULL;
/* Use memcpy to workaround copy->name being const. */
copy = kmalloc(sizeof(*copy), GFP_KERNEL);
memcpy(copy, suite, sizeof(*copy));
filtered = kcalloc(n + 1, sizeof(*filtered), GFP_KERNEL);
n = 0;
kunit_suite_for_each_test_case(suite, test_case) {
if (!test_glob || glob_match(test_glob, test_case->name))
filtered[n++] = *test_case;
}
copy->test_cases = filtered;
return copy;
}
static char *kunit_shutdown;
core_param(kunit_shutdown, kunit_shutdown, charp, 0644);
static struct kunit_suite * const *
kunit_filter_subsuite(struct kunit_suite * const * const subsuite,
struct kunit_test_filter *filter)
{
int i, n = 0;
struct kunit_suite **filtered, *filtered_suite;
n = 0;
for (i = 0; subsuite[i]; ++i) {
if (glob_match(filter->suite_glob, subsuite[i]->name))
++n;
}
if (n == 0)
return NULL;
filtered = kmalloc_array(n + 1, sizeof(*filtered), GFP_KERNEL);
if (!filtered)
return NULL;
n = 0;
for (i = 0; subsuite[i] != NULL; ++i) {
if (!glob_match(filter->suite_glob, subsuite[i]->name))
continue;
filtered_suite = kunit_filter_tests(subsuite[i], filter->test_glob);
if (filtered_suite)
filtered[n++] = filtered_suite;
}
filtered[n] = NULL;
return filtered;
}
struct suite_set {
struct kunit_suite * const * const *start;
struct kunit_suite * const * const *end;
};
static void kunit_free_subsuite(struct kunit_suite * const *subsuite)
{
unsigned int i;
for (i = 0; subsuite[i]; i++)
kfree(subsuite[i]);
kfree(subsuite);
}
static void kunit_free_suite_set(struct suite_set suite_set)
{
struct kunit_suite * const * const *suites;
for (suites = suite_set.start; suites < suite_set.end; suites++)
kunit_free_subsuite(*suites);
kfree(suite_set.start);
}
static struct suite_set kunit_filter_suites(const struct suite_set *suite_set,
const char *filter_glob)
{
int i;
struct kunit_suite * const **copy, * const *filtered_subsuite;
struct suite_set filtered;
struct kunit_test_filter filter;
const size_t max = suite_set->end - suite_set->start;
copy = kmalloc_array(max, sizeof(*filtered.start), GFP_KERNEL);
filtered.start = copy;
if (!copy) { /* won't be able to run anything, return an empty set */
filtered.end = copy;
return filtered;
}
kunit_parse_filter_glob(&filter, filter_glob);
for (i = 0; i < max; ++i) {
filtered_subsuite = kunit_filter_subsuite(suite_set->start[i], &filter);
if (filtered_subsuite)
*copy++ = filtered_subsuite;
}
filtered.end = copy;
kfree(filter.suite_glob);
kfree(filter.test_glob);
return filtered;
}
static void kunit_handle_shutdown(void)
{
if (!kunit_shutdown)
return;
if (!strcmp(kunit_shutdown, "poweroff"))
kernel_power_off();
else if (!strcmp(kunit_shutdown, "halt"))
kernel_halt();
else if (!strcmp(kunit_shutdown, "reboot"))
kernel_restart(NULL);
}
static void kunit_print_tap_header(struct suite_set *suite_set)
{
struct kunit_suite * const * const *suites, * const *subsuite;
int num_of_suites = 0;
for (suites = suite_set->start; suites < suite_set->end; suites++)
for (subsuite = *suites; *subsuite != NULL; subsuite++)
num_of_suites++;
pr_info("TAP version 14\n");
pr_info("1..%d\n", num_of_suites);
}
int kunit_run_all_tests(void)
{
struct kunit_suite * const * const *suites;
struct suite_set suite_set = {
.start = __kunit_suites_start,
.end = __kunit_suites_end,
};
if (filter_glob_param)
suite_set = kunit_filter_suites(&suite_set, filter_glob_param);
kunit_print_tap_header(&suite_set);
for (suites = suite_set.start; suites < suite_set.end; suites++)
__kunit_test_suites_init(*suites);
if (filter_glob_param) { /* a copy was made of each array */
kunit_free_suite_set(suite_set);
}
kunit_handle_shutdown();
return 0;
}
#if IS_BUILTIN(CONFIG_KUNIT_TEST)
#include "executor_test.c"
#endif
#endif /* IS_BUILTIN(CONFIG_KUNIT) */