diff options
Diffstat (limited to 'tools/testing/selftests/bpf/prog_tests/mmap.c')
| -rw-r--r-- | tools/testing/selftests/bpf/prog_tests/mmap.c | 290 |
1 files changed, 290 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/mmap.c b/tools/testing/selftests/bpf/prog_tests/mmap.c new file mode 100644 index 000000000..9c3c5c0f0 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/mmap.c @@ -0,0 +1,290 @@ +// 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_and_load(); + if (CHECK(!skel, "skel_open_and_load", "skeleton open/load failed\n")) + return; + + 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, 4096, PROT_READ | PROT_WRITE, MAP_SHARED, rdmap_fd, 0); + if (CHECK(tmp1 != MAP_FAILED, "rdonly_write_mmap", "unexpected success\n")) { + munmap(tmp1, 4096); + goto cleanup; + } + /* now double-check if it's mmap()'able at all */ + tmp1 = mmap(NULL, 4096, 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); +} |