@cryptotaxi247 / netdata-1 / commits / 132e31ce9

eBPF unittest + bug fix (#15146)

thiagoftsm committed Jun 12, 2023 at 14:35 UTC 132e31ce9e9a56c40c481071ee8993a0607508cc

8 files changed +180 -21

CMakeLists.txt

@@ -620,6 +620,8 @@ set(EBPF_PROCESS_PLUGIN_FILES

620 collectors/ebpf.plugin/ebpf_apps.h

621 collectors/ebpf.plugin/ebpf_cgroup.c

622 collectors/ebpf.plugin/ebpf_cgroup.h

623 + collectors/ebpf.plugin/ebpf_unittest.c

624 + collectors/ebpf.plugin/ebpf_unittest.h

625 )

626

627 set(PROC_PLUGIN_FILES

Makefile.am

@@ -360,6 +360,8 @@ EBPF_PLUGIN_FILES = \

360 collectors/ebpf.plugin/ebpf_apps.h \

361 collectors/ebpf.plugin/ebpf_cgroup.c \

362 collectors/ebpf.plugin/ebpf_cgroup.h \

363 + collectors/ebpf.plugin/ebpf_unittest.c \

364 + collectors/ebpf.plugin/ebpf_unittest.h \

365 $(LIBNETDATA_FILES) \

366 $(NULL)

367

collectors/ebpf.plugin/ebpf.c

+75 -16

@@ -6,6 +6,7 @@

7 #include "ebpf.h"

8 #include "ebpf_socket.h"

9 +#include "ebpf_unittest.h"

10 #include "libnetdata/required_dummies.h"

12 /*****************************************************************

@@ -578,7 +579,7 @@ static void ebpf_exit()

579 * @param objects objects loaded from eBPF programs

580 * @param probe_links links from loader

581 */

581 -static void ebpf_unload_legacy_code(struct bpf_object *objects, struct bpf_link **probe_links)

582 +void ebpf_unload_legacy_code(struct bpf_object *objects, struct bpf_link **probe_links)

583 {

584 if (!probe_links || !objects)

585 return;

@@ -2059,6 +2060,48 @@ static inline void ebpf_load_thread_config()

2060 }

2061 }

2062

2063 +/**

2064 + * Check Conditions

2065 + *

2066 + * This function checks kernel that plugin is running and permissions.

2067 + *

2068 + * @return It returns 0 on success and -1 otherwise

2069 + */

2070 +int ebpf_check_conditions()

2071 +{

2072 + if (!has_condition_to_run(running_on_kernel)) {

2073 + error("The current collector cannot run on this kernel.");

2074 + return -1;

2075 + }

2076 +

2077 + if (!am_i_running_as_root()) {

2078 + error(

2079 + "ebpf.plugin should either run as root (now running with uid %u, euid %u) or have special capabilities..",

2080 + (unsigned int)getuid(), (unsigned int)geteuid());

2081 + return -1;

2082 + }

2083 +

2084 + return 0;

2085 +}

2086 +

2087 +/**

2088 + * Adjust memory

2089 + *

2090 + * Adjust memory values to load eBPF programs.

2091 + *

2092 + * @return It returns 0 on success and -1 otherwise

2093 + */

2094 +int ebpf_adjust_memory_limit()

2095 +{

2096 + struct rlimit r = { RLIM_INFINITY, RLIM_INFINITY };

2097 + if (setrlimit(RLIMIT_MEMLOCK, &r)) {

2098 + error("Setrlimit(RLIMIT_MEMLOCK)");

2099 + return -1;

2100 + }

2101 +

2102 + return 0;

2103 +}

2104 +

2105 /**

2106 * Parse arguments given from user.

2107 *

@@ -2097,6 +2140,7 @@ static void ebpf_parse_args(int argc, char **argv)

2140 {"return", no_argument, 0, 0 },

2141 {"legacy", no_argument, 0, 0 },

2142 {"core", no_argument, 0, 0 },

2143 + {"unittest", no_argument, 0, 0 },

2144 {0, 0, 0, 0}

2145 };

2146

@@ -2287,6 +2331,33 @@ static void ebpf_parse_args(int argc, char **argv)

2331 #endif

2332 break;

2333 }

2334 + case EBPF_OPTION_UNITTEST: {

2335 + // if we cannot run until the end, we will cancel the unittest

2336 + int exit_code = ECANCELED;

2337 + if (ebpf_check_conditions())

2338 + goto unittest;

2339 +

2340 + if (ebpf_adjust_memory_limit())

2341 + goto unittest;

2342 +

2343 + // Load binary in entry mode

2344 + ebpf_ut_initialize_structure(MODE_ENTRY);

2345 + if (ebpf_ut_load_real_binary())

2346 + goto unittest;

2347 +

2348 + ebpf_ut_cleanup_memory();

2349 +

2350 + // Do not load a binary in entry mode

2351 + ebpf_ut_initialize_structure(MODE_ENTRY);

2352 + if (ebpf_ut_load_fake_binary())

2353 + goto unittest;

2354 +

2355 + ebpf_ut_cleanup_memory();

2356 +

2357 + exit_code = 0;

2358 +unittest:

2359 + exit(exit_code);

2360 + }

2361 default: {

2362 break;

2363 }

@@ -2505,17 +2576,8 @@ int main(int argc, char **argv)

2576 ebpf_parse_args(argc, argv);

2577 ebpf_manage_pid(getpid());

2578

2508 - if (!has_condition_to_run(running_on_kernel)) {

2509 - error("The current collector cannot run on this kernel.");

2579 + if (ebpf_check_conditions())

2580 return 2;

2511 - }

2512 -

2513 - if (!am_i_running_as_root()) {

2514 - error(

2515 - "ebpf.plugin should either run as root (now running with uid %u, euid %u) or have special capabilities..",

2516 - (unsigned int)getuid(), (unsigned int)geteuid());

2517 - return 3;

2518 - }

2581

2582 // set name

2583 program_name = "ebpf.plugin";

@@ -2527,11 +2589,8 @@ int main(int argc, char **argv)

2589 error_log_errors_per_period = 100;

2590 error_log_throttle_period = 3600;

2591

2530 - struct rlimit r = { RLIM_INFINITY, RLIM_INFINITY };

2531 - if (setrlimit(RLIMIT_MEMLOCK, &r)) {

2532 - error("Setrlimit(RLIMIT_MEMLOCK)");

2533 - return 4;

2534 - }

2592 + if (ebpf_adjust_memory_limit())

2593 + return 3;

2594

2595 signal(SIGINT, ebpf_stop_threads);

2596 signal(SIGQUIT, ebpf_stop_threads);

collectors/ebpf.plugin/ebpf.h

+4 -1

@@ -119,7 +119,8 @@ enum ebpf_main_index {

119 EBPF_OPTION_GLOBAL_CHART,

120 EBPF_OPTION_RETURN_MODE,

121 EBPF_OPTION_LEGACY,

122 - EBPF_OPTION_CORE

122 + EBPF_OPTION_CORE,

123 + EBPF_OPTION_UNITTEST

124 };

125

126 typedef struct ebpf_tracepoint {

@@ -308,6 +309,8 @@ void ebpf_write_chart_obsolete(char *type, char *id, char *title, char *units, c

309 void write_histogram_chart(char *family, char *name, const netdata_idx_t *hist, char **dimensions, uint32_t end);

310 void ebpf_update_disabled_plugin_stats(ebpf_module_t *em);

311 ARAL *ebpf_allocate_pid_aral(char *name, size_t size);

312 +void ebpf_unload_legacy_code(struct bpf_object *objects, struct bpf_link **probe_links);

313 +

314 extern ebpf_filesystem_partitions_t localfs[];

315 extern ebpf_sync_syscalls_t local_syscalls[];

316 extern int ebpf_exit_plugin;

collectors/ebpf.plugin/ebpf_process.c

+1 -3

@@ -1265,8 +1265,7 @@ void *ebpf_process_thread(void *ptr)

1265 set_local_pointers();

1266 em->probe_links = ebpf_load_program(ebpf_plugin_dir, em, running_on_kernel, isrh, &em->objects);

1267 if (!em->probe_links) {

1268 - pthread_mutex_unlock(&lock);

1269 - goto endprocess;

1268 + em->enabled = em->global_charts = em->apps_charts = em->cgroup_charts = NETDATA_THREAD_EBPF_STOPPING;

1269 }

1270

1271 int algorithms[NETDATA_KEY_PUBLISH_PROCESS_END] = {

@@ -1295,7 +1294,6 @@ void *ebpf_process_thread(void *ptr)

1294

1295 process_collector(em);

1296

1298 -endprocess:

1297 pthread_mutex_lock(&ebpf_exit_cleanup);

1298 if (em->enabled == NETDATA_THREAD_EBPF_RUNNING)

1299 ebpf_update_disabled_plugin_stats(em);

collectors/ebpf.plugin/ebpf_unittest.c new

+83

@@ -0,0 +1,83 @@

1 +// SPDX-License-Identifier: GPL-3.0-or-later

2 +

3 +#include "ebpf_unittest.h"

4 +

5 +ebpf_module_t test_em;

6 +

7 +/**

8 + * Initialize structure

9 + *

10 + * Initialize structure used to run unittests

11 + */

12 +void ebpf_ut_initialize_structure(netdata_run_mode_t mode)

13 +{

14 + memset(&test_em, 0, sizeof(ebpf_module_t));

15 + test_em.thread_name = strdupz("process");

16 + test_em.config_name = test_em.thread_name;

18 + NETDATA_V5_14;

19 + test_em.pid_map_size = ND_EBPF_DEFAULT_PID_SIZE;

20 + test_em.apps_level = NETDATA_APPS_LEVEL_REAL_PARENT;

21 + test_em.mode = mode;

22 +}

23 +

24 +/**

25 + * Clean UP Memory

26 + *

27 + * Clean up allocated data during unit test;

28 + */

29 +void ebpf_ut_cleanup_memory()

30 +{

31 + freez((void *)test_em.thread_name);

32 +}

33 +

34 +/**

35 + * Load Binary

36 + *

37 + * Test load of legacy eBPF programs.

38 + *

39 + * @return It returns 0 on success and -1 otherwise.

40 + */

41 +static int ebpf_ut_load_binary()

42 +{

43 + test_em.probe_links = ebpf_load_program(ebpf_plugin_dir, &test_em, running_on_kernel, isrh, &test_em.objects);

44 + if (!test_em.probe_links)

45 + return -1;

46 +

47 + ebpf_unload_legacy_code(test_em.objects, test_em.probe_links);

48 +

49 + return 0;

50 +}

51 +

52 +/**

53 + * Load Real Binary

54 + *

55 + * Load an existent binary inside plugin directory.

56 + *

57 + * @return It returns 0 on success and -1 otherwise.

58 + */

59 +int ebpf_ut_load_real_binary()

60 +{

61 + return ebpf_ut_load_binary();

62 +}

63 +/**

64 + * Load fake Binary

65 + *

66 + * Try to load a binary not generated by netdata.

67 + *

68 + * @return It returns 0 on success and -1 otherwise. The success for this function means we could work properly with

69 + * expected fails.

70 + */

71 +int ebpf_ut_load_fake_binary()

72 +{

73 + const char *original = test_em.thread_name;

74 +

75 + test_em.thread_name = strdupz("I_am_not_here");

76 + int ret = ebpf_ut_load_binary();

77 +

78 + ebpf_ut_cleanup_memory();

79 +

80 + test_em.thread_name = original;

81 +

82 + return !ret;

83 +}

collectors/ebpf.plugin/ebpf_unittest.h new

+10

@@ -0,0 +1,10 @@

1 +#ifndef NETDATA_EBPF_PLUGIN_UNITTEST_H_

2 +# define NETDATA_EBPF_PLUGIN_UNITTEST_H_ 1

3 +

4 +#include "ebpf.h"

5 +

6 +void ebpf_ut_initialize_structure(netdata_run_mode_t mode);

7 +int ebpf_ut_load_real_binary();

8 +int ebpf_ut_load_fake_binary();

9 +void ebpf_ut_cleanup_memory();

10 +#endif

libnetdata/ebpf/ebpf.c

+3 -1

@@ -856,8 +856,10 @@ struct bpf_link **ebpf_load_program(char *plugins_dir, ebpf_module_t *em, int kv

856 em->load |= EBPF_LOAD_LEGACY;

857

858 *obj = bpf_object__open_file(lpath, NULL);

859 + if (!*obj)

860 + return NULL;

861 +

862 if (libbpf_get_error(obj)) {

860 - error("Cannot open BPF object %s", lpath);

863 bpf_object__close(*obj);

864 return NULL;

865 }