diff options
6 files changed, 509 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c new file mode 100644 index 000000000000..87c29dde1cf9 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c @@ -0,0 +1,409 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2020 Facebook */ +#include <test_progs.h> +#include "bpf_iter_ipv6_route.skel.h" +#include "bpf_iter_netlink.skel.h" +#include "bpf_iter_bpf_map.skel.h" +#include "bpf_iter_task.skel.h" +#include "bpf_iter_task_file.skel.h" +#include "bpf_iter_test_kern1.skel.h" +#include "bpf_iter_test_kern2.skel.h" +#include "bpf_iter_test_kern3.skel.h" +#include "bpf_iter_test_kern4.skel.h" + +static int duration; + +static void test_btf_id_or_null(void) +{ + struct bpf_iter_test_kern3 *skel; + + skel = bpf_iter_test_kern3__open_and_load(); + if (CHECK(skel, "bpf_iter_test_kern3__open_and_load", + "skeleton open_and_load unexpectedly succeeded\n")) { + bpf_iter_test_kern3__destroy(skel); + return; + } +} + +static void do_dummy_read(struct bpf_program *prog) +{ + struct bpf_link *link; + char buf[16] = {}; + int iter_fd, len; + + link = bpf_program__attach_iter(prog, NULL); + if (CHECK(IS_ERR(link), "attach_iter", "attach_iter failed\n")) + return; + + iter_fd = bpf_iter_create(bpf_link__fd(link)); + if (CHECK(iter_fd < 0, "create_iter", "create_iter failed\n")) + goto free_link; + + /* not check contents, but ensure read() ends without error */ + while ((len = read(iter_fd, buf, sizeof(buf))) > 0) + ; + CHECK(len < 0, "read", "read failed: %s\n", strerror(errno)); + + close(iter_fd); + +free_link: + bpf_link__destroy(link); +} + +static void test_ipv6_route(void) +{ + struct bpf_iter_ipv6_route *skel; + + skel = bpf_iter_ipv6_route__open_and_load(); + if (CHECK(!skel, "bpf_iter_ipv6_route__open_and_load", + "skeleton open_and_load failed\n")) + return; + + do_dummy_read(skel->progs.dump_ipv6_route); + + bpf_iter_ipv6_route__destroy(skel); +} + +static void test_netlink(void) +{ + struct bpf_iter_netlink *skel; + + skel = bpf_iter_netlink__open_and_load(); + if (CHECK(!skel, "bpf_iter_netlink__open_and_load", + "skeleton open_and_load failed\n")) + return; + + do_dummy_read(skel->progs.dump_netlink); + + bpf_iter_netlink__destroy(skel); +} + +static void test_bpf_map(void) +{ + struct bpf_iter_bpf_map *skel; + + skel = bpf_iter_bpf_map__open_and_load(); + if (CHECK(!skel, "bpf_iter_bpf_map__open_and_load", + "skeleton open_and_load failed\n")) + return; + + do_dummy_read(skel->progs.dump_bpf_map); + + bpf_iter_bpf_map__destroy(skel); +} + +static void test_task(void) +{ + struct bpf_iter_task *skel; + + skel = bpf_iter_task__open_and_load(); + if (CHECK(!skel, "bpf_iter_task__open_and_load", + "skeleton open_and_load failed\n")) + return; + + do_dummy_read(skel->progs.dump_task); + + bpf_iter_task__destroy(skel); +} + +static void test_task_file(void) +{ + struct bpf_iter_task_file *skel; + + skel = bpf_iter_task_file__open_and_load(); + if (CHECK(!skel, "bpf_iter_task_file__open_and_load", + "skeleton open_and_load failed\n")) + return; + + do_dummy_read(skel->progs.dump_task_file); + + bpf_iter_task_file__destroy(skel); +} + +/* The expected string is less than 16 bytes */ +static int do_read_with_fd(int iter_fd, const char *expected, + bool read_one_char) +{ + int err = -1, len, read_buf_len, start; + char buf[16] = {}; + + read_buf_len = read_one_char ? 1 : 16; + start = 0; + while ((len = read(iter_fd, buf + start, read_buf_len)) > 0) { + start += len; + if (CHECK(start >= 16, "read", "read len %d\n", len)) + return -1; + read_buf_len = read_one_char ? 1 : 16 - start; + } + if (CHECK(len < 0, "read", "read failed: %s\n", strerror(errno))) + return -1; + + err = strcmp(buf, expected); + if (CHECK(err, "read", "incorrect read result: buf %s, expected %s\n", + buf, expected)) + return -1; + + return 0; +} + +static void test_anon_iter(bool read_one_char) +{ + struct bpf_iter_test_kern1 *skel; + struct bpf_link *link; + int iter_fd, err; + + skel = bpf_iter_test_kern1__open_and_load(); + if (CHECK(!skel, "bpf_iter_test_kern1__open_and_load", + "skeleton open_and_load failed\n")) + return; + + err = bpf_iter_test_kern1__attach(skel); + if (CHECK(err, "bpf_iter_test_kern1__attach", + "skeleton attach failed\n")) { + goto out; + } + + link = skel->links.dump_task; + iter_fd = bpf_iter_create(bpf_link__fd(link)); + if (CHECK(iter_fd < 0, "create_iter", "create_iter failed\n")) + goto out; + + do_read_with_fd(iter_fd, "abcd", read_one_char); + close(iter_fd); + +out: + bpf_iter_test_kern1__destroy(skel); +} + +static int do_read(const char *path, const char *expected) +{ + int err, iter_fd; + + iter_fd = open(path, O_RDONLY); + if (CHECK(iter_fd < 0, "open", "open %s failed: %s\n", + path, strerror(errno))) + return -1; + + err = do_read_with_fd(iter_fd, expected, false); + close(iter_fd); + return err; +} + +static void test_file_iter(void) +{ + const char *path = "/sys/fs/bpf/bpf_iter_test1"; + struct bpf_iter_test_kern1 *skel1; + struct bpf_iter_test_kern2 *skel2; + struct bpf_link *link; + int err; + + skel1 = bpf_iter_test_kern1__open_and_load(); + if (CHECK(!skel1, "bpf_iter_test_kern1__open_and_load", + "skeleton open_and_load failed\n")) + return; + + link = bpf_program__attach_iter(skel1->progs.dump_task, NULL); + if (CHECK(IS_ERR(link), "attach_iter", "attach_iter failed\n")) + goto out; + + /* unlink this path if it exists. */ + unlink(path); + + err = bpf_link__pin(link, path); + if (CHECK(err, "pin_iter", "pin_iter to %s failed: %d\n", path, err)) + goto free_link; + + err = do_read(path, "abcd"); + if (err) + goto unlink_path; + + /* file based iterator seems working fine. Let us a link update + * of the underlying link and `cat` the iterator again, its content + * should change. + */ + skel2 = bpf_iter_test_kern2__open_and_load(); + if (CHECK(!skel2, "bpf_iter_test_kern2__open_and_load", + "skeleton open_and_load failed\n")) + goto unlink_path; + + err = bpf_link__update_program(link, skel2->progs.dump_task); + if (CHECK(err, "update_prog", "update_prog failed\n")) + goto destroy_skel2; + + do_read(path, "ABCD"); + +destroy_skel2: + bpf_iter_test_kern2__destroy(skel2); +unlink_path: + unlink(path); +free_link: + bpf_link__destroy(link); +out: + bpf_iter_test_kern1__destroy(skel1); +} + +static void test_overflow(bool test_e2big_overflow, bool ret1) +{ + __u32 map_info_len, total_read_len, expected_read_len; + int err, iter_fd, map1_fd, map2_fd, len; + struct bpf_map_info map_info = {}; + struct bpf_iter_test_kern4 *skel; + struct bpf_link *link; + __u32 page_size; + char *buf; + + skel = bpf_iter_test_kern4__open(); + if (CHECK(!skel, "bpf_iter_test_kern4__open", + "skeleton open failed\n")) + return; + + /* create two maps: bpf program will only do bpf_seq_write + * for these two maps. The goal is one map output almost + * fills seq_file buffer and then the other will trigger + * overflow and needs restart. + */ + map1_fd = bpf_create_map(BPF_MAP_TYPE_ARRAY, 4, 8, 1, 0); + if (CHECK(map1_fd < 0, "bpf_create_map", + "map_creation failed: %s\n", strerror(errno))) + goto out; + map2_fd = bpf_create_map(BPF_MAP_TYPE_ARRAY, 4, 8, 1, 0); + if (CHECK(map2_fd < 0, "bpf_create_map", + "map_creation failed: %s\n", strerror(errno))) + goto free_map1; + + /* bpf_seq_printf kernel buffer is one page, so one map + * bpf_seq_write will mostly fill it, and the other map + * will partially fill and then trigger overflow and need + * bpf_seq_read restart. + */ + page_size = sysconf(_SC_PAGE_SIZE); + + if (test_e2big_overflow) { + skel->rodata->print_len = (page_size + 8) / 8; + expected_read_len = 2 * (page_size + 8); + } else if (!ret1) { + skel->rodata->print_len = (page_size - 8) / 8; + expected_read_len = 2 * (page_size - 8); + } else { + skel->rodata->print_len = 1; + expected_read_len = 2 * 8; + } + skel->rodata->ret1 = ret1; + + if (CHECK(bpf_iter_test_kern4__load(skel), + "bpf_iter_test_kern4__load", "skeleton load failed\n")) + goto free_map2; + + /* setup filtering map_id in bpf program */ + map_info_len = sizeof(map_info); + err = bpf_obj_get_info_by_fd(map1_fd, &map_info, &map_info_len); + if (CHECK(err, "get_map_info", "get map info failed: %s\n", + strerror(errno))) + goto free_map2; + skel->bss->map1_id = map_info.id; + + err = bpf_obj_get_info_by_fd(map2_fd, &map_info, &map_info_len); + if (CHECK(err, "get_map_info", "get map info failed: %s\n", + strerror(errno))) + goto free_map2; + skel->bss->map2_id = map_info.id; + + link = bpf_program__attach_iter(skel->progs.dump_bpf_map, NULL); + if (CHECK(IS_ERR(link), "attach_iter", "attach_iter failed\n")) + goto free_map2; + + iter_fd = bpf_iter_create(bpf_link__fd(link)); + if (CHECK(iter_fd < 0, "create_iter", "create_iter failed\n")) + goto free_link; + + buf = malloc(expected_read_len); + if (!buf) + goto close_iter; + + /* do read */ + total_read_len = 0; + if (test_e2big_overflow) { + while ((len = read(iter_fd, buf, expected_read_len)) > 0) + total_read_len += len; + + CHECK(len != -1 || errno != E2BIG, "read", + "expected ret -1, errno E2BIG, but get ret %d, error %s\n", + len, strerror(errno)); + goto free_buf; + } else if (!ret1) { + while ((len = read(iter_fd, buf, expected_read_len)) > 0) + total_read_len += len; + + if (CHECK(len < 0, "read", "read failed: %s\n", + strerror(errno))) + goto free_buf; + } else { + do { + len = read(iter_fd, buf, expected_read_len); + if (len > 0) + total_read_len += len; + } while (len > 0 || len == -EAGAIN); + + if (CHECK(len < 0, "read", "read failed: %s\n", + strerror(errno))) + goto free_buf; + } + + if (CHECK(total_read_len != expected_read_len, "read", + "total len %u, expected len %u\n", total_read_len, + expected_read_len)) + goto free_buf; + + if (CHECK(skel->bss->map1_accessed != 1, "map1_accessed", + "expected 1 actual %d\n", skel->bss->map1_accessed)) + goto free_buf; + + if (CHECK(skel->bss->map2_accessed != 2, "map2_accessed", + "expected 2 actual %d\n", skel->bss->map2_accessed)) + goto free_buf; + + CHECK(skel->bss->map2_seqnum1 != skel->bss->map2_seqnum2, + "map2_seqnum", "two different seqnum %lld %lld\n", + skel->bss->map2_seqnum1, skel->bss->map2_seqnum2); + +free_buf: + free(buf); +close_iter: + close(iter_fd); +free_link: + bpf_link__destroy(link); +free_map2: + close(map2_fd); +free_map1: + close(map1_fd); +out: + bpf_iter_test_kern4__destroy(skel); +} + +void test_bpf_iter(void) +{ + if (test__start_subtest("btf_id_or_null")) + test_btf_id_or_null(); + if (test__start_subtest("ipv6_route")) + test_ipv6_route(); + if (test__start_subtest("netlink")) + test_netlink(); + if (test__start_subtest("bpf_map")) + test_bpf_map(); + if (test__start_subtest("task")) + test_task(); + if (test__start_subtest("task_file")) + test_task_file(); + if (test__start_subtest("anon")) + test_anon_iter(false); + if (test__start_subtest("anon-read-one-char")) + test_anon_iter(true); + if (test__start_subtest("file")) + test_file_iter(); + if (test__start_subtest("overflow")) + test_overflow(false, false); + if (test__start_subtest("overflow-e2big")) + test_overflow(true, false); + if (test__start_subtest("prog-ret-1")) + test_overflow(false, true); +} diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_test_kern1.c b/tools/testing/selftests/bpf/progs/bpf_iter_test_kern1.c new file mode 100644 index 000000000000..c71a7c283108 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/bpf_iter_test_kern1.c @@ -0,0 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2020 Facebook */ +#define START_CHAR 'a' +#include "bpf_iter_test_kern_common.h" diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_test_kern2.c b/tools/testing/selftests/bpf/progs/bpf_iter_test_kern2.c new file mode 100644 index 000000000000..8bdc8dc07444 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/bpf_iter_test_kern2.c @@ -0,0 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2020 Facebook */ +#define START_CHAR 'A' +#include "bpf_iter_test_kern_common.h" diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_test_kern3.c b/tools/testing/selftests/bpf/progs/bpf_iter_test_kern3.c new file mode 100644 index 000000000000..636a00fa074d --- /dev/null +++ b/tools/testing/selftests/bpf/progs/bpf_iter_test_kern3.c @@ -0,0 +1,18 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2020 Facebook */ +#include "vmlinux.h" +#include <bpf/bpf_helpers.h> + +char _license[] SEC("license") = "GPL"; + +SEC("iter/task") +int dump_task(struct bpf_iter__task *ctx) +{ + struct seq_file *seq = ctx->meta->seq; + struct task_struct *task = ctx->task; + int tgid; + + tgid = task->tgid; + bpf_seq_write(seq, &tgid, sizeof(tgid)); + return 0; +} diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_test_kern4.c b/tools/testing/selftests/bpf/progs/bpf_iter_test_kern4.c new file mode 100644 index 000000000000..b18dc0471d07 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/bpf_iter_test_kern4.c @@ -0,0 +1,52 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2020 Facebook */ +#include "vmlinux.h" +#include <bpf/bpf_helpers.h> + +char _license[] SEC("license") = "GPL"; + +__u32 map1_id = 0, map2_id = 0; +__u32 map1_accessed = 0, map2_accessed = 0; +__u64 map1_seqnum = 0, map2_seqnum1 = 0, map2_seqnum2 = 0; + +static volatile const __u32 print_len; +static volatile const __u32 ret1; + +SEC("iter/bpf_map") +int dump_bpf_map(struct bpf_iter__bpf_map *ctx) +{ + struct seq_file *seq = ctx->meta->seq; + struct bpf_map *map = ctx->map; + __u64 seq_num; + int i, ret = 0; + + if (map == (void *)0) + return 0; + + /* only dump map1_id and map2_id */ + if (map->id != map1_id && map->id != map2_id) + return 0; + + seq_num = ctx->meta->seq_num; + if (map->id == map1_id) { + map1_seqnum = seq_num; + map1_accessed++; + } + + if (map->id == map2_id) { + if (map2_accessed == 0) { + map2_seqnum1 = seq_num; + if (ret1) + ret = 1; + } else { + map2_seqnum2 = seq_num; + } + map2_accessed++; + } + + /* fill seq_file buffer */ + for (i = 0; i < print_len; i++) + bpf_seq_write(seq, &seq_num, sizeof(seq_num)); + + return ret; +} diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_test_kern_common.h b/tools/testing/selftests/bpf/progs/bpf_iter_test_kern_common.h new file mode 100644 index 000000000000..bdd51cf14b54 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/bpf_iter_test_kern_common.h @@ -0,0 +1,22 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Copyright (c) 2020 Facebook */ +#include "vmlinux.h" +#include <bpf/bpf_helpers.h> + +char _license[] SEC("license") = "GPL"; +int count = 0; + +SEC("iter/task") +int dump_task(struct bpf_iter__task *ctx) +{ + struct seq_file *seq = ctx->meta->seq; + char c; + + if (count < 4) { + c = START_CHAR + count; + bpf_seq_write(seq, &c, sizeof(c)); + count++; + } + + return 0; +} |