1 // SPDX-License-Identifier: GPL-2.0-only 2 /* Copyright (c) 2017 Facebook 3 */ 4 #include <linux/bpf.h> 5 #include <linux/slab.h> 6 #include <linux/vmalloc.h> 7 #include <linux/etherdevice.h> 8 #include <linux/filter.h> 9 #include <linux/sched/signal.h> 10 #include <net/bpf_sk_storage.h> 11 #include <net/sock.h> 12 #include <net/tcp.h> 13 14 #define CREATE_TRACE_POINTS 15 #include <trace/events/bpf_test_run.h> 16 17 static int bpf_test_run(struct bpf_prog *prog, void *ctx, u32 repeat, 18 u32 *retval, u32 *time, bool xdp) 19 { 20 struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE] = { NULL }; 21 enum bpf_cgroup_storage_type stype; 22 u64 time_start, time_spent = 0; 23 int ret = 0; 24 u32 i; 25 26 for_each_cgroup_storage_type(stype) { 27 storage[stype] = bpf_cgroup_storage_alloc(prog, stype); 28 if (IS_ERR(storage[stype])) { 29 storage[stype] = NULL; 30 for_each_cgroup_storage_type(stype) 31 bpf_cgroup_storage_free(storage[stype]); 32 return -ENOMEM; 33 } 34 } 35 36 if (!repeat) 37 repeat = 1; 38 39 rcu_read_lock(); 40 preempt_disable(); 41 time_start = ktime_get_ns(); 42 for (i = 0; i < repeat; i++) { 43 bpf_cgroup_storage_set(storage); 44 45 if (xdp) 46 *retval = bpf_prog_run_xdp(prog, ctx); 47 else 48 *retval = BPF_PROG_RUN(prog, ctx); 49 50 if (signal_pending(current)) { 51 ret = -EINTR; 52 break; 53 } 54 55 if (need_resched()) { 56 time_spent += ktime_get_ns() - time_start; 57 preempt_enable(); 58 rcu_read_unlock(); 59 60 cond_resched(); 61 62 rcu_read_lock(); 63 preempt_disable(); 64 time_start = ktime_get_ns(); 65 } 66 } 67 time_spent += ktime_get_ns() - time_start; 68 preempt_enable(); 69 rcu_read_unlock(); 70 71 do_div(time_spent, repeat); 72 *time = time_spent > U32_MAX ? U32_MAX : (u32)time_spent; 73 74 for_each_cgroup_storage_type(stype) 75 bpf_cgroup_storage_free(storage[stype]); 76 77 return ret; 78 } 79 80 static int bpf_test_finish(const union bpf_attr *kattr, 81 union bpf_attr __user *uattr, const void *data, 82 u32 size, u32 retval, u32 duration) 83 { 84 void __user *data_out = u64_to_user_ptr(kattr->test.data_out); 85 int err = -EFAULT; 86 u32 copy_size = size; 87 88 /* Clamp copy if the user has provided a size hint, but copy the full 89 * buffer if not to retain old behaviour. 90 */ 91 if (kattr->test.data_size_out && 92 copy_size > kattr->test.data_size_out) { 93 copy_size = kattr->test.data_size_out; 94 err = -ENOSPC; 95 } 96 97 if (data_out && copy_to_user(data_out, data, copy_size)) 98 goto out; 99 if (copy_to_user(&uattr->test.data_size_out, &size, sizeof(size))) 100 goto out; 101 if (copy_to_user(&uattr->test.retval, &retval, sizeof(retval))) 102 goto out; 103 if (copy_to_user(&uattr->test.duration, &duration, sizeof(duration))) 104 goto out; 105 if (err != -ENOSPC) 106 err = 0; 107 out: 108 trace_bpf_test_finish(&err); 109 return err; 110 } 111 112 /* Integer types of various sizes and pointer combinations cover variety of 113 * architecture dependent calling conventions. 7+ can be supported in the 114 * future. 115 */ 116 int noinline bpf_fentry_test1(int a) 117 { 118 return a + 1; 119 } 120 121 int noinline bpf_fentry_test2(int a, u64 b) 122 { 123 return a + b; 124 } 125 126 int noinline bpf_fentry_test3(char a, int b, u64 c) 127 { 128 return a + b + c; 129 } 130 131 int noinline bpf_fentry_test4(void *a, char b, int c, u64 d) 132 { 133 return (long)a + b + c + d; 134 } 135 136 int noinline bpf_fentry_test5(u64 a, void *b, short c, int d, u64 e) 137 { 138 return a + (long)b + c + d + e; 139 } 140 141 int noinline bpf_fentry_test6(u64 a, void *b, short c, int d, void *e, u64 f) 142 { 143 return a + (long)b + c + d + (long)e + f; 144 } 145 146 static void *bpf_test_init(const union bpf_attr *kattr, u32 size, 147 u32 headroom, u32 tailroom) 148 { 149 void __user *data_in = u64_to_user_ptr(kattr->test.data_in); 150 void *data; 151 152 if (size < ETH_HLEN || size > PAGE_SIZE - headroom - tailroom) 153 return ERR_PTR(-EINVAL); 154 155 data = kzalloc(size + headroom + tailroom, GFP_USER); 156 if (!data) 157 return ERR_PTR(-ENOMEM); 158 159 if (copy_from_user(data + headroom, data_in, size)) { 160 kfree(data); 161 return ERR_PTR(-EFAULT); 162 } 163 if (bpf_fentry_test1(1) != 2 || 164 bpf_fentry_test2(2, 3) != 5 || 165 bpf_fentry_test3(4, 5, 6) != 15 || 166 bpf_fentry_test4((void *)7, 8, 9, 10) != 34 || 167 bpf_fentry_test5(11, (void *)12, 13, 14, 15) != 65 || 168 bpf_fentry_test6(16, (void *)17, 18, 19, (void *)20, 21) != 111) { 169 kfree(data); 170 return ERR_PTR(-EFAULT); 171 } 172 return data; 173 } 174 175 static void *bpf_ctx_init(const union bpf_attr *kattr, u32 max_size) 176 { 177 void __user *data_in = u64_to_user_ptr(kattr->test.ctx_in); 178 void __user *data_out = u64_to_user_ptr(kattr->test.ctx_out); 179 u32 size = kattr->test.ctx_size_in; 180 void *data; 181 int err; 182 183 if (!data_in && !data_out) 184 return NULL; 185 186 data = kzalloc(max_size, GFP_USER); 187 if (!data) 188 return ERR_PTR(-ENOMEM); 189 190 if (data_in) { 191 err = bpf_check_uarg_tail_zero(data_in, max_size, size); 192 if (err) { 193 kfree(data); 194 return ERR_PTR(err); 195 } 196 197 size = min_t(u32, max_size, size); 198 if (copy_from_user(data, data_in, size)) { 199 kfree(data); 200 return ERR_PTR(-EFAULT); 201 } 202 } 203 return data; 204 } 205 206 static int bpf_ctx_finish(const union bpf_attr *kattr, 207 union bpf_attr __user *uattr, const void *data, 208 u32 size) 209 { 210 void __user *data_out = u64_to_user_ptr(kattr->test.ctx_out); 211 int err = -EFAULT; 212 u32 copy_size = size; 213 214 if (!data || !data_out) 215 return 0; 216 217 if (copy_size > kattr->test.ctx_size_out) { 218 copy_size = kattr->test.ctx_size_out; 219 err = -ENOSPC; 220 } 221 222 if (copy_to_user(data_out, data, copy_size)) 223 goto out; 224 if (copy_to_user(&uattr->test.ctx_size_out, &size, sizeof(size))) 225 goto out; 226 if (err != -ENOSPC) 227 err = 0; 228 out: 229 return err; 230 } 231 232 /** 233 * range_is_zero - test whether buffer is initialized 234 * @buf: buffer to check 235 * @from: check from this position 236 * @to: check up until (excluding) this position 237 * 238 * This function returns true if the there is a non-zero byte 239 * in the buf in the range [from,to). 240 */ 241 static inline bool range_is_zero(void *buf, size_t from, size_t to) 242 { 243 return !memchr_inv((u8 *)buf + from, 0, to - from); 244 } 245 246 static int convert___skb_to_skb(struct sk_buff *skb, struct __sk_buff *__skb) 247 { 248 struct qdisc_skb_cb *cb = (struct qdisc_skb_cb *)skb->cb; 249 250 if (!__skb) 251 return 0; 252 253 /* make sure the fields we don't use are zeroed */ 254 if (!range_is_zero(__skb, 0, offsetof(struct __sk_buff, priority))) 255 return -EINVAL; 256 257 /* priority is allowed */ 258 259 if (!range_is_zero(__skb, offsetofend(struct __sk_buff, priority), 260 offsetof(struct __sk_buff, cb))) 261 return -EINVAL; 262 263 /* cb is allowed */ 264 265 if (!range_is_zero(__skb, offsetofend(struct __sk_buff, cb), 266 offsetof(struct __sk_buff, tstamp))) 267 return -EINVAL; 268 269 /* tstamp is allowed */ 270 /* wire_len is allowed */ 271 /* gso_segs is allowed */ 272 273 if (!range_is_zero(__skb, offsetofend(struct __sk_buff, gso_segs), 274 sizeof(struct __sk_buff))) 275 return -EINVAL; 276 277 skb->priority = __skb->priority; 278 skb->tstamp = __skb->tstamp; 279 memcpy(&cb->data, __skb->cb, QDISC_CB_PRIV_LEN); 280 281 if (__skb->wire_len == 0) { 282 cb->pkt_len = skb->len; 283 } else { 284 if (__skb->wire_len < skb->len || 285 __skb->wire_len > GSO_MAX_SIZE) 286 return -EINVAL; 287 cb->pkt_len = __skb->wire_len; 288 } 289 290 if (__skb->gso_segs > GSO_MAX_SEGS) 291 return -EINVAL; 292 skb_shinfo(skb)->gso_segs = __skb->gso_segs; 293 294 return 0; 295 } 296 297 static void convert_skb_to___skb(struct sk_buff *skb, struct __sk_buff *__skb) 298 { 299 struct qdisc_skb_cb *cb = (struct qdisc_skb_cb *)skb->cb; 300 301 if (!__skb) 302 return; 303 304 __skb->priority = skb->priority; 305 __skb->tstamp = skb->tstamp; 306 memcpy(__skb->cb, &cb->data, QDISC_CB_PRIV_LEN); 307 __skb->wire_len = cb->pkt_len; 308 __skb->gso_segs = skb_shinfo(skb)->gso_segs; 309 } 310 311 int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr, 312 union bpf_attr __user *uattr) 313 { 314 bool is_l2 = false, is_direct_pkt_access = false; 315 u32 size = kattr->test.data_size_in; 316 u32 repeat = kattr->test.repeat; 317 struct __sk_buff *ctx = NULL; 318 u32 retval, duration; 319 int hh_len = ETH_HLEN; 320 struct sk_buff *skb; 321 struct sock *sk; 322 void *data; 323 int ret; 324 325 data = bpf_test_init(kattr, size, NET_SKB_PAD + NET_IP_ALIGN, 326 SKB_DATA_ALIGN(sizeof(struct skb_shared_info))); 327 if (IS_ERR(data)) 328 return PTR_ERR(data); 329 330 ctx = bpf_ctx_init(kattr, sizeof(struct __sk_buff)); 331 if (IS_ERR(ctx)) { 332 kfree(data); 333 return PTR_ERR(ctx); 334 } 335 336 switch (prog->type) { 337 case BPF_PROG_TYPE_SCHED_CLS: 338 case BPF_PROG_TYPE_SCHED_ACT: 339 is_l2 = true; 340 /* fall through */ 341 case BPF_PROG_TYPE_LWT_IN: 342 case BPF_PROG_TYPE_LWT_OUT: 343 case BPF_PROG_TYPE_LWT_XMIT: 344 is_direct_pkt_access = true; 345 break; 346 default: 347 break; 348 } 349 350 sk = kzalloc(sizeof(struct sock), GFP_USER); 351 if (!sk) { 352 kfree(data); 353 kfree(ctx); 354 return -ENOMEM; 355 } 356 sock_net_set(sk, current->nsproxy->net_ns); 357 sock_init_data(NULL, sk); 358 359 skb = build_skb(data, 0); 360 if (!skb) { 361 kfree(data); 362 kfree(ctx); 363 kfree(sk); 364 return -ENOMEM; 365 } 366 skb->sk = sk; 367 368 skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN); 369 __skb_put(skb, size); 370 skb->protocol = eth_type_trans(skb, current->nsproxy->net_ns->loopback_dev); 371 skb_reset_network_header(skb); 372 373 if (is_l2) 374 __skb_push(skb, hh_len); 375 if (is_direct_pkt_access) 376 bpf_compute_data_pointers(skb); 377 ret = convert___skb_to_skb(skb, ctx); 378 if (ret) 379 goto out; 380 ret = bpf_test_run(prog, skb, repeat, &retval, &duration, false); 381 if (ret) 382 goto out; 383 if (!is_l2) { 384 if (skb_headroom(skb) < hh_len) { 385 int nhead = HH_DATA_ALIGN(hh_len - skb_headroom(skb)); 386 387 if (pskb_expand_head(skb, nhead, 0, GFP_USER)) { 388 ret = -ENOMEM; 389 goto out; 390 } 391 } 392 memset(__skb_push(skb, hh_len), 0, hh_len); 393 } 394 convert_skb_to___skb(skb, ctx); 395 396 size = skb->len; 397 /* bpf program can never convert linear skb to non-linear */ 398 if (WARN_ON_ONCE(skb_is_nonlinear(skb))) 399 size = skb_headlen(skb); 400 ret = bpf_test_finish(kattr, uattr, skb->data, size, retval, duration); 401 if (!ret) 402 ret = bpf_ctx_finish(kattr, uattr, ctx, 403 sizeof(struct __sk_buff)); 404 out: 405 kfree_skb(skb); 406 bpf_sk_storage_free(sk); 407 kfree(sk); 408 kfree(ctx); 409 return ret; 410 } 411 412 int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr, 413 union bpf_attr __user *uattr) 414 { 415 u32 size = kattr->test.data_size_in; 416 u32 repeat = kattr->test.repeat; 417 struct netdev_rx_queue *rxqueue; 418 struct xdp_buff xdp = {}; 419 u32 retval, duration; 420 void *data; 421 int ret; 422 423 if (kattr->test.ctx_in || kattr->test.ctx_out) 424 return -EINVAL; 425 426 data = bpf_test_init(kattr, size, XDP_PACKET_HEADROOM + NET_IP_ALIGN, 0); 427 if (IS_ERR(data)) 428 return PTR_ERR(data); 429 430 xdp.data_hard_start = data; 431 xdp.data = data + XDP_PACKET_HEADROOM + NET_IP_ALIGN; 432 xdp.data_meta = xdp.data; 433 xdp.data_end = xdp.data + size; 434 435 rxqueue = __netif_get_rx_queue(current->nsproxy->net_ns->loopback_dev, 0); 436 xdp.rxq = &rxqueue->xdp_rxq; 437 bpf_prog_change_xdp(NULL, prog); 438 ret = bpf_test_run(prog, &xdp, repeat, &retval, &duration, true); 439 if (ret) 440 goto out; 441 if (xdp.data != data + XDP_PACKET_HEADROOM + NET_IP_ALIGN || 442 xdp.data_end != xdp.data + size) 443 size = xdp.data_end - xdp.data; 444 ret = bpf_test_finish(kattr, uattr, xdp.data, size, retval, duration); 445 out: 446 bpf_prog_change_xdp(prog, NULL); 447 kfree(data); 448 return ret; 449 } 450 451 static int verify_user_bpf_flow_keys(struct bpf_flow_keys *ctx) 452 { 453 /* make sure the fields we don't use are zeroed */ 454 if (!range_is_zero(ctx, 0, offsetof(struct bpf_flow_keys, flags))) 455 return -EINVAL; 456 457 /* flags is allowed */ 458 459 if (!range_is_zero(ctx, offsetofend(struct bpf_flow_keys, flags), 460 sizeof(struct bpf_flow_keys))) 461 return -EINVAL; 462 463 return 0; 464 } 465 466 int bpf_prog_test_run_flow_dissector(struct bpf_prog *prog, 467 const union bpf_attr *kattr, 468 union bpf_attr __user *uattr) 469 { 470 u32 size = kattr->test.data_size_in; 471 struct bpf_flow_dissector ctx = {}; 472 u32 repeat = kattr->test.repeat; 473 struct bpf_flow_keys *user_ctx; 474 struct bpf_flow_keys flow_keys; 475 u64 time_start, time_spent = 0; 476 const struct ethhdr *eth; 477 unsigned int flags = 0; 478 u32 retval, duration; 479 void *data; 480 int ret; 481 u32 i; 482 483 if (prog->type != BPF_PROG_TYPE_FLOW_DISSECTOR) 484 return -EINVAL; 485 486 if (size < ETH_HLEN) 487 return -EINVAL; 488 489 data = bpf_test_init(kattr, size, 0, 0); 490 if (IS_ERR(data)) 491 return PTR_ERR(data); 492 493 eth = (struct ethhdr *)data; 494 495 if (!repeat) 496 repeat = 1; 497 498 user_ctx = bpf_ctx_init(kattr, sizeof(struct bpf_flow_keys)); 499 if (IS_ERR(user_ctx)) { 500 kfree(data); 501 return PTR_ERR(user_ctx); 502 } 503 if (user_ctx) { 504 ret = verify_user_bpf_flow_keys(user_ctx); 505 if (ret) 506 goto out; 507 flags = user_ctx->flags; 508 } 509 510 ctx.flow_keys = &flow_keys; 511 ctx.data = data; 512 ctx.data_end = (__u8 *)data + size; 513 514 rcu_read_lock(); 515 preempt_disable(); 516 time_start = ktime_get_ns(); 517 for (i = 0; i < repeat; i++) { 518 retval = bpf_flow_dissect(prog, &ctx, eth->h_proto, ETH_HLEN, 519 size, flags); 520 521 if (signal_pending(current)) { 522 preempt_enable(); 523 rcu_read_unlock(); 524 525 ret = -EINTR; 526 goto out; 527 } 528 529 if (need_resched()) { 530 time_spent += ktime_get_ns() - time_start; 531 preempt_enable(); 532 rcu_read_unlock(); 533 534 cond_resched(); 535 536 rcu_read_lock(); 537 preempt_disable(); 538 time_start = ktime_get_ns(); 539 } 540 } 541 time_spent += ktime_get_ns() - time_start; 542 preempt_enable(); 543 rcu_read_unlock(); 544 545 do_div(time_spent, repeat); 546 duration = time_spent > U32_MAX ? U32_MAX : (u32)time_spent; 547 548 ret = bpf_test_finish(kattr, uattr, &flow_keys, sizeof(flow_keys), 549 retval, duration); 550 if (!ret) 551 ret = bpf_ctx_finish(kattr, uattr, user_ctx, 552 sizeof(struct bpf_flow_keys)); 553 554 out: 555 kfree(user_ctx); 556 kfree(data); 557 return ret; 558 } 559