linux/kernel/sysctl-test.c

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// SPDX-License-Identifier: GPL-2.0
/*
* KUnit test of proc sysctl.
*/
#include <kunit/test.h>
#include <linux/sysctl.h>
#define KUNIT_PROC_READ 0
#define KUNIT_PROC_WRITE 1
/*
* Test that proc_dointvec will not try to use a NULL .data field even when the
* length is non-zero.
*/
static void sysctl_test_api_dointvec_null_tbl_data(struct kunit *test)
{
struct ctl_table null_data_table = {
.procname = "foo",
/*
* Here we are testing that proc_dointvec behaves correctly when
* we give it a NULL .data field. Normally this would point to a
* piece of memory where the value would be stored.
*/
.data = NULL,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
.extra1 = SYSCTL_ZERO,
.extra2 = SYSCTL_ONE_HUNDRED,
};
/*
* proc_dointvec expects a buffer in user space, so we allocate one. We
* also need to cast it to __user so sparse doesn't get mad.
*/
void __user *buffer = (void __user *)kunit_kzalloc(test, sizeof(int),
GFP_USER);
size_t len;
loff_t pos;
/*
* We don't care what the starting length is since proc_dointvec should
* not try to read because .data is NULL.
*/
len = 1234;
KUNIT_EXPECT_EQ(test, 0, proc_dointvec(&null_data_table,
KUNIT_PROC_READ, buffer, &len,
&pos));
KUNIT_EXPECT_EQ(test, 0, len);
/*
* See above.
*/
len = 1234;
KUNIT_EXPECT_EQ(test, 0, proc_dointvec(&null_data_table,
KUNIT_PROC_WRITE, buffer, &len,
&pos));
KUNIT_EXPECT_EQ(test, 0, len);
}
/*
* Similar to the previous test, we create a struct ctrl_table that has a .data
* field that proc_dointvec cannot do anything with; however, this time it is
* because we tell proc_dointvec that the size is 0.
*/
static void sysctl_test_api_dointvec_table_maxlen_unset(struct kunit *test)
{
int data = 0;
struct ctl_table data_maxlen_unset_table = {
.procname = "foo",
.data = &data,
/*
* So .data is no longer NULL, but we tell proc_dointvec its
* length is 0, so it still shouldn't try to use it.
*/
.maxlen = 0,
.mode = 0644,
.proc_handler = proc_dointvec,
.extra1 = SYSCTL_ZERO,
.extra2 = SYSCTL_ONE_HUNDRED,
};
void __user *buffer = (void __user *)kunit_kzalloc(test, sizeof(int),
GFP_USER);
size_t len;
loff_t pos;
/*
* As before, we don't care what buffer length is because proc_dointvec
* cannot do anything because its internal .data buffer has zero length.
*/
len = 1234;
KUNIT_EXPECT_EQ(test, 0, proc_dointvec(&data_maxlen_unset_table,
KUNIT_PROC_READ, buffer, &len,
&pos));
KUNIT_EXPECT_EQ(test, 0, len);
/*
* See previous comment.
*/
len = 1234;
KUNIT_EXPECT_EQ(test, 0, proc_dointvec(&data_maxlen_unset_table,
KUNIT_PROC_WRITE, buffer, &len,
&pos));
KUNIT_EXPECT_EQ(test, 0, len);
}
/*
* Here we provide a valid struct ctl_table, but we try to read and write from
* it using a buffer of zero length, so it should still fail in a similar way as
* before.
*/
static void sysctl_test_api_dointvec_table_len_is_zero(struct kunit *test)
{
int data = 0;
/* Good table. */
struct ctl_table table = {
.procname = "foo",
.data = &data,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
.extra1 = SYSCTL_ZERO,
.extra2 = SYSCTL_ONE_HUNDRED,
};
void __user *buffer = (void __user *)kunit_kzalloc(test, sizeof(int),
GFP_USER);
/*
* However, now our read/write buffer has zero length.
*/
size_t len = 0;
loff_t pos;
KUNIT_EXPECT_EQ(test, 0, proc_dointvec(&table, KUNIT_PROC_READ, buffer,
&len, &pos));
KUNIT_EXPECT_EQ(test, 0, len);
KUNIT_EXPECT_EQ(test, 0, proc_dointvec(&table, KUNIT_PROC_WRITE, buffer,
&len, &pos));
KUNIT_EXPECT_EQ(test, 0, len);
}
/*
* Test that proc_dointvec refuses to read when the file position is non-zero.
*/
static void sysctl_test_api_dointvec_table_read_but_position_set(
struct kunit *test)
{
int data = 0;
/* Good table. */
struct ctl_table table = {
.procname = "foo",
.data = &data,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
.extra1 = SYSCTL_ZERO,
.extra2 = SYSCTL_ONE_HUNDRED,
};
void __user *buffer = (void __user *)kunit_kzalloc(test, sizeof(int),
GFP_USER);
/*
* We don't care about our buffer length because we start off with a
* non-zero file position.
*/
size_t len = 1234;
/*
* proc_dointvec should refuse to read into the buffer since the file
* pos is non-zero.
*/
loff_t pos = 1;
KUNIT_EXPECT_EQ(test, 0, proc_dointvec(&table, KUNIT_PROC_READ, buffer,
&len, &pos));
KUNIT_EXPECT_EQ(test, 0, len);
}
/*
* Test that we can read a two digit number in a sufficiently size buffer.
* Nothing fancy.
*/
static void sysctl_test_dointvec_read_happy_single_positive(struct kunit *test)
{
int data = 0;
/* Good table. */
struct ctl_table table = {
.procname = "foo",
.data = &data,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
.extra1 = SYSCTL_ZERO,
.extra2 = SYSCTL_ONE_HUNDRED,
};
size_t len = 4;
loff_t pos = 0;
char *buffer = kunit_kzalloc(test, len, GFP_USER);
char __user *user_buffer = (char __user *)buffer;
/* Store 13 in the data field. */
*((int *)table.data) = 13;
KUNIT_EXPECT_EQ(test, 0, proc_dointvec(&table, KUNIT_PROC_READ,
user_buffer, &len, &pos));
KUNIT_ASSERT_EQ(test, 3, len);
buffer[len] = '\0';
/* And we read 13 back out. */
KUNIT_EXPECT_STREQ(test, "13\n", buffer);
}
/*
* Same as previous test, just now with negative numbers.
*/
static void sysctl_test_dointvec_read_happy_single_negative(struct kunit *test)
{
int data = 0;
/* Good table. */
struct ctl_table table = {
.procname = "foo",
.data = &data,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
.extra1 = SYSCTL_ZERO,
.extra2 = SYSCTL_ONE_HUNDRED,
};
size_t len = 5;
loff_t pos = 0;
char *buffer = kunit_kzalloc(test, len, GFP_USER);
char __user *user_buffer = (char __user *)buffer;
*((int *)table.data) = -16;
KUNIT_EXPECT_EQ(test, 0, proc_dointvec(&table, KUNIT_PROC_READ,
user_buffer, &len, &pos));
KUNIT_ASSERT_EQ(test, 4, len);
buffer[len] = '\0';
KUNIT_EXPECT_STREQ(test, "-16\n", buffer);
}
/*
* Test that a simple positive write works.
*/
static void sysctl_test_dointvec_write_happy_single_positive(struct kunit *test)
{
int data = 0;
/* Good table. */
struct ctl_table table = {
.procname = "foo",
.data = &data,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
.extra1 = SYSCTL_ZERO,
.extra2 = SYSCTL_ONE_HUNDRED,
};
char input[] = "9";
size_t len = sizeof(input) - 1;
loff_t pos = 0;
char *buffer = kunit_kzalloc(test, len, GFP_USER);
char __user *user_buffer = (char __user *)buffer;
memcpy(buffer, input, len);
KUNIT_EXPECT_EQ(test, 0, proc_dointvec(&table, KUNIT_PROC_WRITE,
user_buffer, &len, &pos));
KUNIT_EXPECT_EQ(test, sizeof(input) - 1, len);
KUNIT_EXPECT_EQ(test, sizeof(input) - 1, pos);
KUNIT_EXPECT_EQ(test, 9, *((int *)table.data));
}
/*
* Same as previous test, but now with negative numbers.
*/
static void sysctl_test_dointvec_write_happy_single_negative(struct kunit *test)
{
int data = 0;
struct ctl_table table = {
.procname = "foo",
.data = &data,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
.extra1 = SYSCTL_ZERO,
.extra2 = SYSCTL_ONE_HUNDRED,
};
char input[] = "-9";
size_t len = sizeof(input) - 1;
loff_t pos = 0;
char *buffer = kunit_kzalloc(test, len, GFP_USER);
char __user *user_buffer = (char __user *)buffer;
memcpy(buffer, input, len);
KUNIT_EXPECT_EQ(test, 0, proc_dointvec(&table, KUNIT_PROC_WRITE,
user_buffer, &len, &pos));
KUNIT_EXPECT_EQ(test, sizeof(input) - 1, len);
KUNIT_EXPECT_EQ(test, sizeof(input) - 1, pos);
KUNIT_EXPECT_EQ(test, -9, *((int *)table.data));
}
/*
* Test that writing a value smaller than the minimum possible value is not
* allowed.
*/
static void sysctl_test_api_dointvec_write_single_less_int_min(
struct kunit *test)
{
int data = 0;
struct ctl_table table = {
.procname = "foo",
.data = &data,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
.extra1 = SYSCTL_ZERO,
.extra2 = SYSCTL_ONE_HUNDRED,
};
size_t max_len = 32, len = max_len;
loff_t pos = 0;
char *buffer = kunit_kzalloc(test, max_len, GFP_USER);
char __user *user_buffer = (char __user *)buffer;
unsigned long abs_of_less_than_min = (unsigned long)INT_MAX
- (INT_MAX + INT_MIN) + 1;
/*
* We use this rigmarole to create a string that contains a value one
* less than the minimum accepted value.
*/
KUNIT_ASSERT_LT(test,
(size_t)snprintf(buffer, max_len, "-%lu",
abs_of_less_than_min),
max_len);
KUNIT_EXPECT_EQ(test, -EINVAL, proc_dointvec(&table, KUNIT_PROC_WRITE,
user_buffer, &len, &pos));
KUNIT_EXPECT_EQ(test, max_len, len);
KUNIT_EXPECT_EQ(test, 0, *((int *)table.data));
}
/*
* Test that writing the maximum possible value works.
*/
static void sysctl_test_api_dointvec_write_single_greater_int_max(
struct kunit *test)
{
int data = 0;
struct ctl_table table = {
.procname = "foo",
.data = &data,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
.extra1 = SYSCTL_ZERO,
.extra2 = SYSCTL_ONE_HUNDRED,
};
size_t max_len = 32, len = max_len;
loff_t pos = 0;
char *buffer = kunit_kzalloc(test, max_len, GFP_USER);
char __user *user_buffer = (char __user *)buffer;
unsigned long greater_than_max = (unsigned long)INT_MAX + 1;
KUNIT_ASSERT_GT(test, greater_than_max, (unsigned long)INT_MAX);
KUNIT_ASSERT_LT(test, (size_t)snprintf(buffer, max_len, "%lu",
greater_than_max),
max_len);
KUNIT_EXPECT_EQ(test, -EINVAL, proc_dointvec(&table, KUNIT_PROC_WRITE,
user_buffer, &len, &pos));
KUNIT_ASSERT_EQ(test, max_len, len);
KUNIT_EXPECT_EQ(test, 0, *((int *)table.data));
}
static struct kunit_case sysctl_test_cases[] = {
KUNIT_CASE(sysctl_test_api_dointvec_null_tbl_data),
KUNIT_CASE(sysctl_test_api_dointvec_table_maxlen_unset),
KUNIT_CASE(sysctl_test_api_dointvec_table_len_is_zero),
KUNIT_CASE(sysctl_test_api_dointvec_table_read_but_position_set),
KUNIT_CASE(sysctl_test_dointvec_read_happy_single_positive),
KUNIT_CASE(sysctl_test_dointvec_read_happy_single_negative),
KUNIT_CASE(sysctl_test_dointvec_write_happy_single_positive),
KUNIT_CASE(sysctl_test_dointvec_write_happy_single_negative),
KUNIT_CASE(sysctl_test_api_dointvec_write_single_less_int_min),
KUNIT_CASE(sysctl_test_api_dointvec_write_single_greater_int_max),
{}
};
static struct kunit_suite sysctl_test_suite = {
.name = "sysctl_test",
.test_cases = sysctl_test_cases,
};
kunit: allow kunit tests to be loaded as a module As tests are added to kunit, it will become less feasible to execute all built tests together. By supporting modular tests we provide a simple way to do selective execution on a running system; specifying CONFIG_KUNIT=y CONFIG_KUNIT_EXAMPLE_TEST=m ...means we can simply "insmod example-test.ko" to run the tests. To achieve this we need to do the following: o export the required symbols in kunit o string-stream tests utilize non-exported symbols so for now we skip building them when CONFIG_KUNIT_TEST=m. o drivers/base/power/qos-test.c contains a few unexported interface references, namely freq_qos_read_value() and freq_constraints_init(). Both of these could be potentially defined as static inline functions in include/linux/pm_qos.h, but for now we simply avoid supporting module build for that test suite. o support a new way of declaring test suites. Because a module cannot do multiple late_initcall()s, we provide a kunit_test_suites() macro to declare multiple suites within the same module at once. o some test module names would have been too general ("test-test" and "example-test" for kunit tests, "inode-test" for ext4 tests); rename these as appropriate ("kunit-test", "kunit-example-test" and "ext4-inode-test" respectively). Also define kunit_test_suite() via kunit_test_suites() as callers in other trees may need the old definition. Co-developed-by: Knut Omang <knut.omang@oracle.com> Signed-off-by: Knut Omang <knut.omang@oracle.com> Signed-off-by: Alan Maguire <alan.maguire@oracle.com> Reviewed-by: Brendan Higgins <brendanhiggins@google.com> Acked-by: Theodore Ts'o <tytso@mit.edu> # for ext4 bits Acked-by: David Gow <davidgow@google.com> # For list-test Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-01-06 22:28:20 +00:00
kunit_test_suites(&sysctl_test_suite);
MODULE_LICENSE("GPL v2");