kernel/sysctl-test: Add null pointer test for sysctl.c:proc_dointvec()
[ Upstream commit 2cb80dbbbaba4f2f86f686c34cb79ea5cbfb0edb ] KUnit tests for initialized data behavior of proc_dointvec that is explicitly checked in the code. Includes basic parsing tests including int min/max overflow. Signed-off-by: Iurii Zaikin <yzaikin@google.com> Signed-off-by: Brendan Higgins <brendanhiggins@google.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Acked-by: Luis Chamberlain <mcgrof@kernel.org> Reviewed-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Iurii Zaikin
Greg Kroah-Hartman
parent
5d087e3578
commit
03c4d42e3c
@ -115,6 +115,8 @@ obj-$(CONFIG_TORTURE_TEST) += torture.o
|
||||
obj-$(CONFIG_HAS_IOMEM) += iomem.o
|
||||
obj-$(CONFIG_RSEQ) += rseq.o
|
||||
|
||||
obj-$(CONFIG_SYSCTL_KUNIT_TEST) += sysctl-test.o
|
||||
|
||||
obj-$(CONFIG_GCC_PLUGIN_STACKLEAK) += stackleak.o
|
||||
KASAN_SANITIZE_stackleak.o := n
|
||||
KCOV_INSTRUMENT_stackleak.o := n
|
||||
|
||||
392
kernel/sysctl-test.c
Normal file
392
kernel/sysctl-test.c
Normal file
@ -0,0 +1,392 @@
|
||||
// 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
|
||||
|
||||
static int i_zero;
|
||||
static int i_one_hundred = 100;
|
||||
|
||||
/*
|
||||
* 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 = &i_zero,
|
||||
.extra2 = &i_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, (size_t)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, (size_t)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 = &i_zero,
|
||||
.extra2 = &i_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, (size_t)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, (size_t)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 = &i_zero,
|
||||
.extra2 = &i_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, (size_t)0, len);
|
||||
|
||||
KUNIT_EXPECT_EQ(test, 0, proc_dointvec(&table, KUNIT_PROC_WRITE, buffer,
|
||||
&len, &pos));
|
||||
KUNIT_EXPECT_EQ(test, (size_t)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 = &i_zero,
|
||||
.extra2 = &i_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, (size_t)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 = &i_zero,
|
||||
.extra2 = &i_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, (size_t)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 = &i_zero,
|
||||
.extra2 = &i_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, (size_t)4, len);
|
||||
buffer[len] = '\0';
|
||||
KUNIT_EXPECT_STREQ(test, "-16\n", (char *)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 = &i_zero,
|
||||
.extra2 = &i_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, (size_t)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 = &i_zero,
|
||||
.extra2 = &i_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, (size_t)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 = &i_zero,
|
||||
.extra2 = &i_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 = &i_zero,
|
||||
.extra2 = &i_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_test_suite(sysctl_test_suite);
|
||||
@ -1939,6 +1939,17 @@ config TEST_SYSCTL
|
||||
|
||||
If unsure, say N.
|
||||
|
||||
config SYSCTL_KUNIT_TEST
|
||||
bool "KUnit test for sysctl"
|
||||
depends on KUNIT
|
||||
help
|
||||
This builds the proc sysctl unit test, which runs on boot.
|
||||
Tests the API contract and implementation correctness of sysctl.
|
||||
For more information on KUnit and unit tests in general please refer
|
||||
to the KUnit documentation in Documentation/dev-tools/kunit/.
|
||||
|
||||
If unsure, say N.
|
||||
|
||||
config TEST_UDELAY
|
||||
tristate "udelay test driver"
|
||||
help
|
||||
|
||||
Loading…
Reference in New Issue
Block a user