| // SPDX-License-Identifier: GPL-2.0 |
| #include <test_progs.h> |
| #include <sys/mman.h> |
| #include "test_mmap.skel.h" |
| |
| struct map_data { |
| __u64 val[512 * 4]; |
| }; |
| |
| static size_t roundup_page(size_t sz) |
| { |
| long page_size = sysconf(_SC_PAGE_SIZE); |
| return (sz + page_size - 1) / page_size * page_size; |
| } |
| |
| void test_mmap(void) |
| { |
| const size_t bss_sz = roundup_page(sizeof(struct test_mmap__bss)); |
| const size_t map_sz = roundup_page(sizeof(struct map_data)); |
| const int zero = 0, one = 1, two = 2, far = 1500; |
| const long page_size = sysconf(_SC_PAGE_SIZE); |
| int err, duration = 0, i, data_map_fd, data_map_id, tmp_fd, rdmap_fd; |
| struct bpf_map *data_map, *bss_map; |
| void *bss_mmaped = NULL, *map_mmaped = NULL, *tmp0, *tmp1, *tmp2; |
| struct test_mmap__bss *bss_data; |
| struct bpf_map_info map_info; |
| __u32 map_info_sz = sizeof(map_info); |
| struct map_data *map_data; |
| struct test_mmap *skel; |
| __u64 val = 0; |
| |
| skel = test_mmap__open(); |
| if (CHECK(!skel, "skel_open", "skeleton open failed\n")) |
| return; |
| |
| err = bpf_map__set_max_entries(skel->maps.rdonly_map, page_size); |
| if (CHECK(err != 0, "bpf_map__set_max_entries", "bpf_map__set_max_entries failed\n")) |
| goto cleanup; |
| |
| /* at least 4 pages of data */ |
| err = bpf_map__set_max_entries(skel->maps.data_map, |
| 4 * (page_size / sizeof(u64))); |
| if (CHECK(err != 0, "bpf_map__set_max_entries", "bpf_map__set_max_entries failed\n")) |
| goto cleanup; |
| |
| err = test_mmap__load(skel); |
| if (CHECK(err != 0, "skel_load", "skeleton load failed\n")) |
| goto cleanup; |
| |
| bss_map = skel->maps.bss; |
| data_map = skel->maps.data_map; |
| data_map_fd = bpf_map__fd(data_map); |
| |
| rdmap_fd = bpf_map__fd(skel->maps.rdonly_map); |
| tmp1 = mmap(NULL, page_size, PROT_READ | PROT_WRITE, MAP_SHARED, rdmap_fd, 0); |
| if (CHECK(tmp1 != MAP_FAILED, "rdonly_write_mmap", "unexpected success\n")) { |
| munmap(tmp1, page_size); |
| goto cleanup; |
| } |
| /* now double-check if it's mmap()'able at all */ |
| tmp1 = mmap(NULL, page_size, PROT_READ, MAP_SHARED, rdmap_fd, 0); |
| if (CHECK(tmp1 == MAP_FAILED, "rdonly_read_mmap", "failed: %d\n", errno)) |
| goto cleanup; |
| |
| /* get map's ID */ |
| memset(&map_info, 0, map_info_sz); |
| err = bpf_obj_get_info_by_fd(data_map_fd, &map_info, &map_info_sz); |
| if (CHECK(err, "map_get_info", "failed %d\n", errno)) |
| goto cleanup; |
| data_map_id = map_info.id; |
| |
| /* mmap BSS map */ |
| bss_mmaped = mmap(NULL, bss_sz, PROT_READ | PROT_WRITE, MAP_SHARED, |
| bpf_map__fd(bss_map), 0); |
| if (CHECK(bss_mmaped == MAP_FAILED, "bss_mmap", |
| ".bss mmap failed: %d\n", errno)) { |
| bss_mmaped = NULL; |
| goto cleanup; |
| } |
| /* map as R/W first */ |
| map_mmaped = mmap(NULL, map_sz, PROT_READ | PROT_WRITE, MAP_SHARED, |
| data_map_fd, 0); |
| if (CHECK(map_mmaped == MAP_FAILED, "data_mmap", |
| "data_map mmap failed: %d\n", errno)) { |
| map_mmaped = NULL; |
| goto cleanup; |
| } |
| |
| bss_data = bss_mmaped; |
| map_data = map_mmaped; |
| |
| CHECK_FAIL(bss_data->in_val); |
| CHECK_FAIL(bss_data->out_val); |
| CHECK_FAIL(skel->bss->in_val); |
| CHECK_FAIL(skel->bss->out_val); |
| CHECK_FAIL(map_data->val[0]); |
| CHECK_FAIL(map_data->val[1]); |
| CHECK_FAIL(map_data->val[2]); |
| CHECK_FAIL(map_data->val[far]); |
| |
| err = test_mmap__attach(skel); |
| if (CHECK(err, "attach_raw_tp", "err %d\n", err)) |
| goto cleanup; |
| |
| bss_data->in_val = 123; |
| val = 111; |
| CHECK_FAIL(bpf_map_update_elem(data_map_fd, &zero, &val, 0)); |
| |
| usleep(1); |
| |
| CHECK_FAIL(bss_data->in_val != 123); |
| CHECK_FAIL(bss_data->out_val != 123); |
| CHECK_FAIL(skel->bss->in_val != 123); |
| CHECK_FAIL(skel->bss->out_val != 123); |
| CHECK_FAIL(map_data->val[0] != 111); |
| CHECK_FAIL(map_data->val[1] != 222); |
| CHECK_FAIL(map_data->val[2] != 123); |
| CHECK_FAIL(map_data->val[far] != 3 * 123); |
| |
| CHECK_FAIL(bpf_map_lookup_elem(data_map_fd, &zero, &val)); |
| CHECK_FAIL(val != 111); |
| CHECK_FAIL(bpf_map_lookup_elem(data_map_fd, &one, &val)); |
| CHECK_FAIL(val != 222); |
| CHECK_FAIL(bpf_map_lookup_elem(data_map_fd, &two, &val)); |
| CHECK_FAIL(val != 123); |
| CHECK_FAIL(bpf_map_lookup_elem(data_map_fd, &far, &val)); |
| CHECK_FAIL(val != 3 * 123); |
| |
| /* data_map freeze should fail due to R/W mmap() */ |
| err = bpf_map_freeze(data_map_fd); |
| if (CHECK(!err || errno != EBUSY, "no_freeze", |
| "data_map freeze succeeded: err=%d, errno=%d\n", err, errno)) |
| goto cleanup; |
| |
| err = mprotect(map_mmaped, map_sz, PROT_READ); |
| if (CHECK(err, "mprotect_ro", "mprotect to r/o failed %d\n", errno)) |
| goto cleanup; |
| |
| /* unmap R/W mapping */ |
| err = munmap(map_mmaped, map_sz); |
| map_mmaped = NULL; |
| if (CHECK(err, "data_map_munmap", "data_map munmap failed: %d\n", errno)) |
| goto cleanup; |
| |
| /* re-map as R/O now */ |
| map_mmaped = mmap(NULL, map_sz, PROT_READ, MAP_SHARED, data_map_fd, 0); |
| if (CHECK(map_mmaped == MAP_FAILED, "data_mmap", |
| "data_map R/O mmap failed: %d\n", errno)) { |
| map_mmaped = NULL; |
| goto cleanup; |
| } |
| err = mprotect(map_mmaped, map_sz, PROT_WRITE); |
| if (CHECK(!err, "mprotect_wr", "mprotect() succeeded unexpectedly!\n")) |
| goto cleanup; |
| err = mprotect(map_mmaped, map_sz, PROT_EXEC); |
| if (CHECK(!err, "mprotect_ex", "mprotect() succeeded unexpectedly!\n")) |
| goto cleanup; |
| map_data = map_mmaped; |
| |
| /* map/unmap in a loop to test ref counting */ |
| for (i = 0; i < 10; i++) { |
| int flags = i % 2 ? PROT_READ : PROT_WRITE; |
| void *p; |
| |
| p = mmap(NULL, map_sz, flags, MAP_SHARED, data_map_fd, 0); |
| if (CHECK_FAIL(p == MAP_FAILED)) |
| goto cleanup; |
| err = munmap(p, map_sz); |
| if (CHECK_FAIL(err)) |
| goto cleanup; |
| } |
| |
| /* data_map freeze should now succeed due to no R/W mapping */ |
| err = bpf_map_freeze(data_map_fd); |
| if (CHECK(err, "freeze", "data_map freeze failed: err=%d, errno=%d\n", |
| err, errno)) |
| goto cleanup; |
| |
| /* mapping as R/W now should fail */ |
| tmp1 = mmap(NULL, map_sz, PROT_READ | PROT_WRITE, MAP_SHARED, |
| data_map_fd, 0); |
| if (CHECK(tmp1 != MAP_FAILED, "data_mmap", "mmap succeeded\n")) { |
| munmap(tmp1, map_sz); |
| goto cleanup; |
| } |
| |
| bss_data->in_val = 321; |
| usleep(1); |
| CHECK_FAIL(bss_data->in_val != 321); |
| CHECK_FAIL(bss_data->out_val != 321); |
| CHECK_FAIL(skel->bss->in_val != 321); |
| CHECK_FAIL(skel->bss->out_val != 321); |
| CHECK_FAIL(map_data->val[0] != 111); |
| CHECK_FAIL(map_data->val[1] != 222); |
| CHECK_FAIL(map_data->val[2] != 321); |
| CHECK_FAIL(map_data->val[far] != 3 * 321); |
| |
| /* check some more advanced mmap() manipulations */ |
| |
| tmp0 = mmap(NULL, 4 * page_size, PROT_READ, MAP_SHARED | MAP_ANONYMOUS, |
| -1, 0); |
| if (CHECK(tmp0 == MAP_FAILED, "adv_mmap0", "errno %d\n", errno)) |
| goto cleanup; |
| |
| /* map all but last page: pages 1-3 mapped */ |
| tmp1 = mmap(tmp0, 3 * page_size, PROT_READ, MAP_SHARED | MAP_FIXED, |
| data_map_fd, 0); |
| if (CHECK(tmp0 != tmp1, "adv_mmap1", "tmp0: %p, tmp1: %p\n", tmp0, tmp1)) { |
| munmap(tmp0, 4 * page_size); |
| goto cleanup; |
| } |
| |
| /* unmap second page: pages 1, 3 mapped */ |
| err = munmap(tmp1 + page_size, page_size); |
| if (CHECK(err, "adv_mmap2", "errno %d\n", errno)) { |
| munmap(tmp1, 4 * page_size); |
| goto cleanup; |
| } |
| |
| /* map page 2 back */ |
| tmp2 = mmap(tmp1 + page_size, page_size, PROT_READ, |
| MAP_SHARED | MAP_FIXED, data_map_fd, 0); |
| if (CHECK(tmp2 == MAP_FAILED, "adv_mmap3", "errno %d\n", errno)) { |
| munmap(tmp1, page_size); |
| munmap(tmp1 + 2*page_size, 2 * page_size); |
| goto cleanup; |
| } |
| CHECK(tmp1 + page_size != tmp2, "adv_mmap4", |
| "tmp1: %p, tmp2: %p\n", tmp1, tmp2); |
| |
| /* re-map all 4 pages */ |
| tmp2 = mmap(tmp1, 4 * page_size, PROT_READ, MAP_SHARED | MAP_FIXED, |
| data_map_fd, 0); |
| if (CHECK(tmp2 == MAP_FAILED, "adv_mmap5", "errno %d\n", errno)) { |
| munmap(tmp1, 4 * page_size); /* unmap page 1 */ |
| goto cleanup; |
| } |
| CHECK(tmp1 != tmp2, "adv_mmap6", "tmp1: %p, tmp2: %p\n", tmp1, tmp2); |
| |
| map_data = tmp2; |
| CHECK_FAIL(bss_data->in_val != 321); |
| CHECK_FAIL(bss_data->out_val != 321); |
| CHECK_FAIL(skel->bss->in_val != 321); |
| CHECK_FAIL(skel->bss->out_val != 321); |
| CHECK_FAIL(map_data->val[0] != 111); |
| CHECK_FAIL(map_data->val[1] != 222); |
| CHECK_FAIL(map_data->val[2] != 321); |
| CHECK_FAIL(map_data->val[far] != 3 * 321); |
| |
| munmap(tmp2, 4 * page_size); |
| |
| /* map all 4 pages, but with pg_off=1 page, should fail */ |
| tmp1 = mmap(NULL, 4 * page_size, PROT_READ, MAP_SHARED | MAP_FIXED, |
| data_map_fd, page_size /* initial page shift */); |
| if (CHECK(tmp1 != MAP_FAILED, "adv_mmap7", "unexpected success")) { |
| munmap(tmp1, 4 * page_size); |
| goto cleanup; |
| } |
| |
| tmp1 = mmap(NULL, map_sz, PROT_READ, MAP_SHARED, data_map_fd, 0); |
| if (CHECK(tmp1 == MAP_FAILED, "last_mmap", "failed %d\n", errno)) |
| goto cleanup; |
| |
| test_mmap__destroy(skel); |
| skel = NULL; |
| CHECK_FAIL(munmap(bss_mmaped, bss_sz)); |
| bss_mmaped = NULL; |
| CHECK_FAIL(munmap(map_mmaped, map_sz)); |
| map_mmaped = NULL; |
| |
| /* map should be still held by active mmap */ |
| tmp_fd = bpf_map_get_fd_by_id(data_map_id); |
| if (CHECK(tmp_fd < 0, "get_map_by_id", "failed %d\n", errno)) { |
| munmap(tmp1, map_sz); |
| goto cleanup; |
| } |
| close(tmp_fd); |
| |
| /* this should release data map finally */ |
| munmap(tmp1, map_sz); |
| |
| /* we need to wait for RCU grace period */ |
| for (i = 0; i < 10000; i++) { |
| __u32 id = data_map_id - 1; |
| if (bpf_map_get_next_id(id, &id) || id > data_map_id) |
| break; |
| usleep(1); |
| } |
| |
| /* should fail to get map FD by non-existing ID */ |
| tmp_fd = bpf_map_get_fd_by_id(data_map_id); |
| if (CHECK(tmp_fd >= 0, "get_map_by_id_after", |
| "unexpectedly succeeded %d\n", tmp_fd)) { |
| close(tmp_fd); |
| goto cleanup; |
| } |
| |
| cleanup: |
| if (bss_mmaped) |
| CHECK_FAIL(munmap(bss_mmaped, bss_sz)); |
| if (map_mmaped) |
| CHECK_FAIL(munmap(map_mmaped, map_sz)); |
| test_mmap__destroy(skel); |
| } |