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