1// SPDX-License-Identifier: GPL-2.0 2#include <test_progs.h> 3#include <sys/mman.h> 4#include "test_mmap.skel.h" 5 6struct map_data { 7 __u64 val[512 * 4]; 8}; 9 10static size_t roundup_page(size_t sz) 11{ 12 long page_size = sysconf(_SC_PAGE_SIZE); 13 return (sz + page_size - 1) / page_size * page_size; 14} 15 16void test_mmap(void) 17{ 18 const size_t bss_sz = roundup_page(sizeof(struct test_mmap__bss)); 19 const size_t map_sz = roundup_page(sizeof(struct map_data)); 20 const int zero = 0, one = 1, two = 2, far = 1500; 21 const long page_size = sysconf(_SC_PAGE_SIZE); 22 int err, duration = 0, i, data_map_fd, data_map_id, tmp_fd, rdmap_fd; 23 struct bpf_map *data_map, *bss_map; 24 void *bss_mmaped = NULL, *map_mmaped = NULL, *tmp0, *tmp1, *tmp2; 25 struct test_mmap__bss *bss_data; 26 struct bpf_map_info map_info; 27 __u32 map_info_sz = sizeof(map_info); 28 struct map_data *map_data; 29 struct test_mmap *skel; 30 __u64 val = 0; 31 32 skel = test_mmap__open_and_load(); 33 if (CHECK(!skel, "skel_open_and_load", "skeleton open/load failed\n")) 34 return; 35 36 bss_map = skel->maps.bss; 37 data_map = skel->maps.data_map; 38 data_map_fd = bpf_map__fd(data_map); 39 40 rdmap_fd = bpf_map__fd(skel->maps.rdonly_map); 41 tmp1 = mmap(NULL, 4096, PROT_READ | PROT_WRITE, MAP_SHARED, rdmap_fd, 0); 42 if (CHECK(tmp1 != MAP_FAILED, "rdonly_write_mmap", "unexpected success\n")) { 43 munmap(tmp1, 4096); 44 goto cleanup; 45 } 46 /* now double-check if it's mmap()'able at all */ 47 tmp1 = mmap(NULL, 4096, PROT_READ, MAP_SHARED, rdmap_fd, 0); 48 if (CHECK(tmp1 == MAP_FAILED, "rdonly_read_mmap", "failed: %d\n", errno)) 49 goto cleanup; 50 51 /* get map's ID */ 52 memset(&map_info, 0, map_info_sz); 53 err = bpf_obj_get_info_by_fd(data_map_fd, &map_info, &map_info_sz); 54 if (CHECK(err, "map_get_info", "failed %d\n", errno)) 55 goto cleanup; 56 data_map_id = map_info.id; 57 58 /* mmap BSS map */ 59 bss_mmaped = mmap(NULL, bss_sz, PROT_READ | PROT_WRITE, MAP_SHARED, 60 bpf_map__fd(bss_map), 0); 61 if (CHECK(bss_mmaped == MAP_FAILED, "bss_mmap", 62 ".bss mmap failed: %d\n", errno)) { 63 bss_mmaped = NULL; 64 goto cleanup; 65 } 66 /* map as R/W first */ 67 map_mmaped = mmap(NULL, map_sz, PROT_READ | PROT_WRITE, MAP_SHARED, 68 data_map_fd, 0); 69 if (CHECK(map_mmaped == MAP_FAILED, "data_mmap", 70 "data_map mmap failed: %d\n", errno)) { 71 map_mmaped = NULL; 72 goto cleanup; 73 } 74 75 bss_data = bss_mmaped; 76 map_data = map_mmaped; 77 78 CHECK_FAIL(bss_data->in_val); 79 CHECK_FAIL(bss_data->out_val); 80 CHECK_FAIL(skel->bss->in_val); 81 CHECK_FAIL(skel->bss->out_val); 82 CHECK_FAIL(map_data->val[0]); 83 CHECK_FAIL(map_data->val[1]); 84 CHECK_FAIL(map_data->val[2]); 85 CHECK_FAIL(map_data->val[far]); 86 87 err = test_mmap__attach(skel); 88 if (CHECK(err, "attach_raw_tp", "err %d\n", err)) 89 goto cleanup; 90 91 bss_data->in_val = 123; 92 val = 111; 93 CHECK_FAIL(bpf_map_update_elem(data_map_fd, &zero, &val, 0)); 94 95 usleep(1); 96 97 CHECK_FAIL(bss_data->in_val != 123); 98 CHECK_FAIL(bss_data->out_val != 123); 99 CHECK_FAIL(skel->bss->in_val != 123); 100 CHECK_FAIL(skel->bss->out_val != 123); 101 CHECK_FAIL(map_data->val[0] != 111); 102 CHECK_FAIL(map_data->val[1] != 222); 103 CHECK_FAIL(map_data->val[2] != 123); 104 CHECK_FAIL(map_data->val[far] != 3 * 123); 105 106 CHECK_FAIL(bpf_map_lookup_elem(data_map_fd, &zero, &val)); 107 CHECK_FAIL(val != 111); 108 CHECK_FAIL(bpf_map_lookup_elem(data_map_fd, &one, &val)); 109 CHECK_FAIL(val != 222); 110 CHECK_FAIL(bpf_map_lookup_elem(data_map_fd, &two, &val)); 111 CHECK_FAIL(val != 123); 112 CHECK_FAIL(bpf_map_lookup_elem(data_map_fd, &far, &val)); 113 CHECK_FAIL(val != 3 * 123); 114 115 /* data_map freeze should fail due to R/W mmap() */ 116 err = bpf_map_freeze(data_map_fd); 117 if (CHECK(!err || errno != EBUSY, "no_freeze", 118 "data_map freeze succeeded: err=%d, errno=%d\n", err, errno)) 119 goto cleanup; 120 121 err = mprotect(map_mmaped, map_sz, PROT_READ); 122 if (CHECK(err, "mprotect_ro", "mprotect to r/o failed %d\n", errno)) 123 goto cleanup; 124 125 /* unmap R/W mapping */ 126 err = munmap(map_mmaped, map_sz); 127 map_mmaped = NULL; 128 if (CHECK(err, "data_map_munmap", "data_map munmap failed: %d\n", errno)) 129 goto cleanup; 130 131 /* re-map as R/O now */ 132 map_mmaped = mmap(NULL, map_sz, PROT_READ, MAP_SHARED, data_map_fd, 0); 133 if (CHECK(map_mmaped == MAP_FAILED, "data_mmap", 134 "data_map R/O mmap failed: %d\n", errno)) { 135 map_mmaped = NULL; 136 goto cleanup; 137 } 138 err = mprotect(map_mmaped, map_sz, PROT_WRITE); 139 if (CHECK(!err, "mprotect_wr", "mprotect() succeeded unexpectedly!\n")) 140 goto cleanup; 141 err = mprotect(map_mmaped, map_sz, PROT_EXEC); 142 if (CHECK(!err, "mprotect_ex", "mprotect() succeeded unexpectedly!\n")) 143 goto cleanup; 144 map_data = map_mmaped; 145 146 /* map/unmap in a loop to test ref counting */ 147 for (i = 0; i < 10; i++) { 148 int flags = i % 2 ? PROT_READ : PROT_WRITE; 149 void *p; 150 151 p = mmap(NULL, map_sz, flags, MAP_SHARED, data_map_fd, 0); 152 if (CHECK_FAIL(p == MAP_FAILED)) 153 goto cleanup; 154 err = munmap(p, map_sz); 155 if (CHECK_FAIL(err)) 156 goto cleanup; 157 } 158 159 /* data_map freeze should now succeed due to no R/W mapping */ 160 err = bpf_map_freeze(data_map_fd); 161 if (CHECK(err, "freeze", "data_map freeze failed: err=%d, errno=%d\n", 162 err, errno)) 163 goto cleanup; 164 165 /* mapping as R/W now should fail */ 166 tmp1 = mmap(NULL, map_sz, PROT_READ | PROT_WRITE, MAP_SHARED, 167 data_map_fd, 0); 168 if (CHECK(tmp1 != MAP_FAILED, "data_mmap", "mmap succeeded\n")) { 169 munmap(tmp1, map_sz); 170 goto cleanup; 171 } 172 173 bss_data->in_val = 321; 174 usleep(1); 175 CHECK_FAIL(bss_data->in_val != 321); 176 CHECK_FAIL(bss_data->out_val != 321); 177 CHECK_FAIL(skel->bss->in_val != 321); 178 CHECK_FAIL(skel->bss->out_val != 321); 179 CHECK_FAIL(map_data->val[0] != 111); 180 CHECK_FAIL(map_data->val[1] != 222); 181 CHECK_FAIL(map_data->val[2] != 321); 182 CHECK_FAIL(map_data->val[far] != 3 * 321); 183 184 /* check some more advanced mmap() manipulations */ 185 186 tmp0 = mmap(NULL, 4 * page_size, PROT_READ, MAP_SHARED | MAP_ANONYMOUS, 187 -1, 0); 188 if (CHECK(tmp0 == MAP_FAILED, "adv_mmap0", "errno %d\n", errno)) 189 goto cleanup; 190 191 /* map all but last page: pages 1-3 mapped */ 192 tmp1 = mmap(tmp0, 3 * page_size, PROT_READ, MAP_SHARED | MAP_FIXED, 193 data_map_fd, 0); 194 if (CHECK(tmp0 != tmp1, "adv_mmap1", "tmp0: %p, tmp1: %p\n", tmp0, tmp1)) { 195 munmap(tmp0, 4 * page_size); 196 goto cleanup; 197 } 198 199 /* unmap second page: pages 1, 3 mapped */ 200 err = munmap(tmp1 + page_size, page_size); 201 if (CHECK(err, "adv_mmap2", "errno %d\n", errno)) { 202 munmap(tmp1, 4 * page_size); 203 goto cleanup; 204 } 205 206 /* map page 2 back */ 207 tmp2 = mmap(tmp1 + page_size, page_size, PROT_READ, 208 MAP_SHARED | MAP_FIXED, data_map_fd, 0); 209 if (CHECK(tmp2 == MAP_FAILED, "adv_mmap3", "errno %d\n", errno)) { 210 munmap(tmp1, page_size); 211 munmap(tmp1 + 2*page_size, 2 * page_size); 212 goto cleanup; 213 } 214 CHECK(tmp1 + page_size != tmp2, "adv_mmap4", 215 "tmp1: %p, tmp2: %p\n", tmp1, tmp2); 216 217 /* re-map all 4 pages */ 218 tmp2 = mmap(tmp1, 4 * page_size, PROT_READ, MAP_SHARED | MAP_FIXED, 219 data_map_fd, 0); 220 if (CHECK(tmp2 == MAP_FAILED, "adv_mmap5", "errno %d\n", errno)) { 221 munmap(tmp1, 4 * page_size); /* unmap page 1 */ 222 goto cleanup; 223 } 224 CHECK(tmp1 != tmp2, "adv_mmap6", "tmp1: %p, tmp2: %p\n", tmp1, tmp2); 225 226 map_data = tmp2; 227 CHECK_FAIL(bss_data->in_val != 321); 228 CHECK_FAIL(bss_data->out_val != 321); 229 CHECK_FAIL(skel->bss->in_val != 321); 230 CHECK_FAIL(skel->bss->out_val != 321); 231 CHECK_FAIL(map_data->val[0] != 111); 232 CHECK_FAIL(map_data->val[1] != 222); 233 CHECK_FAIL(map_data->val[2] != 321); 234 CHECK_FAIL(map_data->val[far] != 3 * 321); 235 236 munmap(tmp2, 4 * page_size); 237 238 /* map all 4 pages, but with pg_off=1 page, should fail */ 239 tmp1 = mmap(NULL, 4 * page_size, PROT_READ, MAP_SHARED | MAP_FIXED, 240 data_map_fd, page_size /* initial page shift */); 241 if (CHECK(tmp1 != MAP_FAILED, "adv_mmap7", "unexpected success")) { 242 munmap(tmp1, 4 * page_size); 243 goto cleanup; 244 } 245 246 tmp1 = mmap(NULL, map_sz, PROT_READ, MAP_SHARED, data_map_fd, 0); 247 if (CHECK(tmp1 == MAP_FAILED, "last_mmap", "failed %d\n", errno)) 248 goto cleanup; 249 250 test_mmap__destroy(skel); 251 skel = NULL; 252 CHECK_FAIL(munmap(bss_mmaped, bss_sz)); 253 bss_mmaped = NULL; 254 CHECK_FAIL(munmap(map_mmaped, map_sz)); 255 map_mmaped = NULL; 256 257 /* map should be still held by active mmap */ 258 tmp_fd = bpf_map_get_fd_by_id(data_map_id); 259 if (CHECK(tmp_fd < 0, "get_map_by_id", "failed %d\n", errno)) { 260 munmap(tmp1, map_sz); 261 goto cleanup; 262 } 263 close(tmp_fd); 264 265 /* this should release data map finally */ 266 munmap(tmp1, map_sz); 267 268 /* we need to wait for RCU grace period */ 269 for (i = 0; i < 10000; i++) { 270 __u32 id = data_map_id - 1; 271 if (bpf_map_get_next_id(id, &id) || id > data_map_id) 272 break; 273 usleep(1); 274 } 275 276 /* should fail to get map FD by non-existing ID */ 277 tmp_fd = bpf_map_get_fd_by_id(data_map_id); 278 if (CHECK(tmp_fd >= 0, "get_map_by_id_after", 279 "unexpectedly succeeded %d\n", tmp_fd)) { 280 close(tmp_fd); 281 goto cleanup; 282 } 283 284cleanup: 285 if (bss_mmaped) 286 CHECK_FAIL(munmap(bss_mmaped, bss_sz)); 287 if (map_mmaped) 288 CHECK_FAIL(munmap(map_mmaped, map_sz)); 289 test_mmap__destroy(skel); 290} 291