KUnit tests for decoding extended 64 bit timestamps that verify the seconds part of [a/c/m] timestamps in ext4 inode structs are decoded correctly.

Test data is derived from the table in the Inode Timestamps section of Documentation/filesystems/ext4/inodes.rst.

KUnit tests run during boot and output the results to the debug log in TAP format (http://testanything.org/). Only useful for kernel devs running KUnit test harness and are not for inclusion into a production build.

Signed-off-by: Iurii Zaikin yzaikin@google.com Reviewed-by: Theodore Ts'o tytso@mit.edu Reviewed-by: Brendan Higgins brendanhiggins@google.com Tested-by: Brendan Higgins brendanhiggins@google.com --- fs/ext4/Kconfig | 17 +++ fs/ext4/Makefile | 1 + fs/ext4/inode-test.c | 272 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 290 insertions(+) create mode 100644 fs/ext4/inode-test.c

diff --git a/fs/ext4/Kconfig b/fs/ext4/Kconfig index cbb5ca830e57..ef42ab040905 100644 --- a/fs/ext4/Kconfig +++ b/fs/ext4/Kconfig @@ -106,3 +106,20 @@ config EXT4_DEBUG If you select Y here, then you will be able to turn on debugging with a command such as: echo 1 > /sys/module/ext4/parameters/mballoc_debug + +config EXT4_KUNIT_TESTS + bool "KUnit tests for ext4" + select EXT4_FS + depends on KUNIT + help + This builds the ext4 KUnit tests. + + KUnit tests run during boot and output the results to the debug log + in TAP format (http://testanything.org/). Only useful for kernel devs + running KUnit test harness and are not for inclusion into a production + build. + + 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. diff --git a/fs/ext4/Makefile b/fs/ext4/Makefile index b17ddc229ac5..840b91d040f1 100644 --- a/fs/ext4/Makefile +++ b/fs/ext4/Makefile @@ -13,4 +13,5 @@ ext4-y := balloc.o bitmap.o block_validity.o dir.o ext4_jbd2.o extents.o \

ext4-$(CONFIG_EXT4_FS_POSIX_ACL) += acl.o ext4-$(CONFIG_EXT4_FS_SECURITY) += xattr_security.o +ext4-$(CONFIG_EXT4_KUNIT_TESTS) += inode-test.o ext4-$(CONFIG_FS_VERITY) += verity.o diff --git a/fs/ext4/inode-test.c b/fs/ext4/inode-test.c new file mode 100644 index 000000000000..92a9da1774aa --- /dev/null +++ b/fs/ext4/inode-test.c @@ -0,0 +1,272 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * KUnit test of ext4 inode that verify the seconds part of [a/c/m] + * timestamps in ext4 inode structs are decoded correctly. + */ + +#include <kunit/test.h> +#include <linux/kernel.h> +#include <linux/time64.h> + +#include "ext4.h" + +/* + * For constructing the nonnegative timestamp lower bound value. + * binary: 00000000 00000000 00000000 00000000 + */ +#define LOWER_MSB_0 0L +/* + * For constructing the nonnegative timestamp upper bound value. + * binary: 01111111 11111111 11111111 11111111 + * + */ +#define UPPER_MSB_0 0x7fffffffL +/* + * For constructing the negative timestamp lower bound value. + * binary: 10000000 00000000 00000000 00000000 + */ +#define LOWER_MSB_1 (-0x80000000L) +/* + * For constructing the negative timestamp upper bound value. + * binary: 11111111 11111111 11111111 11111111 + */ +#define UPPER_MSB_1 (-1L) +/* + * Upper bound for nanoseconds value supported by the encoding. + * binary: 00111111 11111111 11111111 11111111 + */ +#define MAX_NANOSECONDS ((1L << 30) - 1) + +#define CASE_NAME_FORMAT "%s: msb:%x lower_bound:%x extra_bits: %x" + +#define LOWER_BOUND_NEG_NO_EXTRA_BITS_CASE\ + "1901-12-13 Lower bound of 32bit < 0 timestamp, no extra bits" +#define UPPER_BOUND_NEG_NO_EXTRA_BITS_CASE\ + "1969-12-31 Upper bound of 32bit < 0 timestamp, no extra bits" +#define LOWER_BOUND_NONNEG_NO_EXTRA_BITS_CASE\ + "1970-01-01 Lower bound of 32bit >=0 timestamp, no extra bits" +#define UPPER_BOUND_NONNEG_NO_EXTRA_BITS_CASE\ + "2038-01-19 Upper bound of 32bit >=0 timestamp, no extra bits" +#define LOWER_BOUND_NEG_LO_1_CASE\ + "2038-01-19 Lower bound of 32bit <0 timestamp, lo extra sec bit on" +#define UPPER_BOUND_NEG_LO_1_CASE\ + "2106-02-07 Upper bound of 32bit <0 timestamp, lo extra sec bit on" +#define LOWER_BOUND_NONNEG_LO_1_CASE\ + "2106-02-07 Lower bound of 32bit >=0 timestamp, lo extra sec bit on" +#define UPPER_BOUND_NONNEG_LO_1_CASE\ + "2174-02-25 Upper bound of 32bit >=0 timestamp, lo extra sec bit on" +#define LOWER_BOUND_NEG_HI_1_CASE\ + "2174-02-25 Lower bound of 32bit <0 timestamp, hi extra sec bit on" +#define UPPER_BOUND_NEG_HI_1_CASE\ + "2242-03-16 Upper bound of 32bit <0 timestamp, hi extra sec bit on" +#define LOWER_BOUND_NONNEG_HI_1_CASE\ + "2242-03-16 Lower bound of 32bit >=0 timestamp, hi extra sec bit on" +#define UPPER_BOUND_NONNEG_HI_1_CASE\ + "2310-04-04 Upper bound of 32bit >=0 timestamp, hi extra sec bit on" +#define UPPER_BOUND_NONNEG_HI_1_NS_1_CASE\ + "2310-04-04 Upper bound of 32bit>=0 timestamp, hi extra sec bit 1. 1 ns" +#define LOWER_BOUND_NONNEG_HI_1_NS_MAX_CASE\ + "2378-04-22 Lower bound of 32bit>= timestamp. Extra sec bits 1. Max ns" +#define LOWER_BOUND_NONNEG_EXTRA_BITS_1_CASE\ + "2378-04-22 Lower bound of 32bit >=0 timestamp. All extra sec bits on" +#define UPPER_BOUND_NONNEG_EXTRA_BITS_1_CASE\ + "2446-05-10 Upper bound of 32bit >=0 timestamp. All extra sec bits on" + +struct timestamp_expectation { + const char *test_case_name; + struct timespec64 expected; + u32 extra_bits; + bool msb_set; + bool lower_bound; +}; + +static time64_t get_32bit_time(const struct timestamp_expectation * const test) +{ + if (test->msb_set) { + if (test->lower_bound) + return LOWER_MSB_1; + + return UPPER_MSB_1; + } + + if (test->lower_bound) + return LOWER_MSB_0; + return UPPER_MSB_0; +} + + +/* + * Test data is derived from the table in the Inode Timestamps section of + * Documentation/filesystems/ext4/inodes.rst. + */ +static void inode_test_xtimestamp_decoding(struct kunit *test) +{ + const struct timestamp_expectation test_data[] = { + { + .test_case_name = LOWER_BOUND_NEG_NO_EXTRA_BITS_CASE, + .msb_set = true, + .lower_bound = true, + .extra_bits = 0, + .expected = {.tv_sec = -0x80000000LL, .tv_nsec = 0L}, + }, + + { + .test_case_name = UPPER_BOUND_NEG_NO_EXTRA_BITS_CASE, + .msb_set = true, + .lower_bound = false, + .extra_bits = 0, + .expected = {.tv_sec = -1LL, .tv_nsec = 0L}, + }, + + { + .test_case_name = LOWER_BOUND_NONNEG_NO_EXTRA_BITS_CASE, + .msb_set = false, + .lower_bound = true, + .extra_bits = 0, + .expected = {0LL, 0L}, + }, + + { + .test_case_name = UPPER_BOUND_NONNEG_NO_EXTRA_BITS_CASE, + .msb_set = false, + .lower_bound = false, + .extra_bits = 0, + .expected = {.tv_sec = 0x7fffffffLL, .tv_nsec = 0L}, + }, + + { + .test_case_name = LOWER_BOUND_NEG_LO_1_CASE, + .msb_set = true, + .lower_bound = true, + .extra_bits = 1, + .expected = {.tv_sec = 0x80000000LL, .tv_nsec = 0L}, + }, + + { + .test_case_name = UPPER_BOUND_NEG_LO_1_CASE, + .msb_set = true, + .lower_bound = false, + .extra_bits = 1, + .expected = {.tv_sec = 0xffffffffLL, .tv_nsec = 0L}, + }, + + { + .test_case_name = LOWER_BOUND_NONNEG_LO_1_CASE, + .msb_set = false, + .lower_bound = true, + .extra_bits = 1, + .expected = {.tv_sec = 0x100000000LL, .tv_nsec = 0L}, + }, + + { + .test_case_name = UPPER_BOUND_NONNEG_LO_1_CASE, + .msb_set = false, + .lower_bound = false, + .extra_bits = 1, + .expected = {.tv_sec = 0x17fffffffLL, .tv_nsec = 0L}, + }, + + { + .test_case_name = LOWER_BOUND_NEG_HI_1_CASE, + .msb_set = true, + .lower_bound = true, + .extra_bits = 2, + .expected = {.tv_sec = 0x180000000LL, .tv_nsec = 0L}, + }, + + { + .test_case_name = UPPER_BOUND_NEG_HI_1_CASE, + .msb_set = true, + .lower_bound = false, + .extra_bits = 2, + .expected = {.tv_sec = 0x1ffffffffLL, .tv_nsec = 0L}, + }, + + { + .test_case_name = LOWER_BOUND_NONNEG_HI_1_CASE, + .msb_set = false, + .lower_bound = true, + .extra_bits = 2, + .expected = {.tv_sec = 0x200000000LL, .tv_nsec = 0L}, + }, + + { + .test_case_name = UPPER_BOUND_NONNEG_HI_1_CASE, + .msb_set = false, + .lower_bound = false, + .extra_bits = 2, + .expected = {.tv_sec = 0x27fffffffLL, .tv_nsec = 0L}, + }, + + { + .test_case_name = UPPER_BOUND_NONNEG_HI_1_NS_1_CASE, + .msb_set = false, + .lower_bound = false, + .extra_bits = 6, + .expected = {.tv_sec = 0x27fffffffLL, .tv_nsec = 1L}, + }, + + { + .test_case_name = LOWER_BOUND_NONNEG_HI_1_NS_MAX_CASE, + .msb_set = false, + .lower_bound = true, + .extra_bits = 0xFFFFFFFF, + .expected = {.tv_sec = 0x300000000LL, + .tv_nsec = MAX_NANOSECONDS}, + }, + + { + .test_case_name = LOWER_BOUND_NONNEG_EXTRA_BITS_1_CASE, + .msb_set = false, + .lower_bound = true, + .extra_bits = 3, + .expected = {.tv_sec = 0x300000000LL, .tv_nsec = 0L}, + }, + + { + .test_case_name = UPPER_BOUND_NONNEG_EXTRA_BITS_1_CASE, + .msb_set = false, + .lower_bound = false, + .extra_bits = 3, + .expected = {.tv_sec = 0x37fffffffLL, .tv_nsec = 0L}, + } + }; + + struct timespec64 timestamp; + int i; + + for (i = 0; i < ARRAY_SIZE(test_data); ++i) { + timestamp.tv_sec = get_32bit_time(&test_data[i]); + ext4_decode_extra_time(&timestamp, + cpu_to_le32(test_data[i].extra_bits)); + + KUNIT_EXPECT_EQ_MSG(test, + test_data[i].expected.tv_sec, + timestamp.tv_sec, + CASE_NAME_FORMAT, + test_data[i].test_case_name, + test_data[i].msb_set, + test_data[i].lower_bound, + test_data[i].extra_bits); + KUNIT_EXPECT_EQ_MSG(test, + test_data[i].expected.tv_nsec, + timestamp.tv_nsec, + CASE_NAME_FORMAT, + test_data[i].test_case_name, + test_data[i].msb_set, + test_data[i].lower_bound, + test_data[i].extra_bits); + } +} + +static struct kunit_case ext4_inode_test_cases[] = { + KUNIT_CASE(inode_test_xtimestamp_decoding), + {} +}; + +static struct kunit_suite ext4_inode_test_suite = { + .name = "ext4_inode_test", + .test_cases = ext4_inode_test_cases, +}; + +kunit_test_suite(ext4_inode_test_suite); -- 2.23.0.866.gb869b98d4c-goog