net/bpf/test_run.c

   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 #include <linux/error-injection.h>
  14 #include <linux/smp.h>
  15
  16 #define CREATE_TRACE_POINTS
  17 #include <trace/events/bpf_test_run.h>
  18
  19 static int bpf_test_run(struct bpf_prog *prog, void *ctx, u32 repeat,
  20                         u32 *retval, u32 *time, bool xdp)
  21 {
  22         struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE] = { NULL };
  23         enum bpf_cgroup_storage_type stype;
  24         u64 time_start, time_spent = 0;
  25         int ret = 0;
  26         u32 i;
  27
  28         for_each_cgroup_storage_type(stype) {
  29                 storage[stype] = bpf_cgroup_storage_alloc(prog, stype);
  30                 if (IS_ERR(storage[stype])) {
  31                         storage[stype] = NULL;
  32                         for_each_cgroup_storage_type(stype)
  33                                 bpf_cgroup_storage_free(storage[stype]);
  34                         return -ENOMEM;
  35                 }
  36         }
  37
  38         if (!repeat)
  39                 repeat = 1;
  40
  41         rcu_read_lock();
  42         migrate_disable();
  43         time_start = ktime_get_ns();
  44         for (i = 0; i < repeat; i++) {
  45                 bpf_cgroup_storage_set(storage);
  46
  47                 if (xdp)
  48                         *retval = bpf_prog_run_xdp(prog, ctx);
  49                 else
  50                         *retval = BPF_PROG_RUN(prog, ctx);
  51
  52                 if (signal_pending(current)) {
  53                         ret = -EINTR;
  54                         break;
  55                 }
  56
  57                 if (need_resched()) {
  58                         time_spent += ktime_get_ns() - time_start;
  59                         migrate_enable();
  60                         rcu_read_unlock();
  61
  62                         cond_resched();
  63
  64                         rcu_read_lock();
  65                         migrate_disable();
  66                         time_start = ktime_get_ns();
  67                 }
  68         }
  69         time_spent += ktime_get_ns() - time_start;
  70         migrate_enable();
  71         rcu_read_unlock();
  72
  73         do_div(time_spent, repeat);
  74         *time = time_spent > U32_MAX ? U32_MAX : (u32)time_spent;
  75
  76         for_each_cgroup_storage_type(stype)
  77                 bpf_cgroup_storage_free(storage[stype]);
  78
  79         return ret;
  80 }
  81
  82 static int bpf_test_finish(const union bpf_attr *kattr,
  83                            union bpf_attr __user *uattr, const void *data,
  84                            u32 size, u32 retval, u32 duration)
  85 {
  86         void __user *data_out = u64_to_user_ptr(kattr->test.data_out);
  87         int err = -EFAULT;
  88         u32 copy_size = size;
  89
  90         /* Clamp copy if the user has provided a size hint, but copy the full
  91          * buffer if not to retain old behaviour.
  92          */
  93         if (kattr->test.data_size_out &&
  94             copy_size > kattr->test.data_size_out) {
  95                 copy_size = kattr->test.data_size_out;
  96                 err = -ENOSPC;
  97         }
  98
  99         if (data_out && copy_to_user(data_out, data, copy_size))
 100                 goto out;
 101         if (copy_to_user(&uattr->test.data_size_out, &size, sizeof(size)))
 102                 goto out;
 103         if (copy_to_user(&uattr->test.retval, &retval, sizeof(retval)))
 104                 goto out;
 105         if (copy_to_user(&uattr->test.duration, &duration, sizeof(duration)))
 106                 goto out;
 107         if (err != -ENOSPC)
 108                 err = 0;
 109 out:
 110         trace_bpf_test_finish(&err);
 111         return err;
 112 }
 113
 114 /* Integer types of various sizes and pointer combinations cover variety of
 115  * architecture dependent calling conventions. 7+ can be supported in the
 116  * future.
 117  */
 118 __diag_push();
 119 __diag_ignore(GCC, 8, "-Wmissing-prototypes",
 120               "Global functions as their definitions will be in vmlinux BTF");
 121 int noinline bpf_fentry_test1(int a)
 122 {
 123         return a + 1;
 124 }
 125
 126 int noinline bpf_fentry_test2(int a, u64 b)
 127 {
 128         return a + b;
 129 }
 130
 131 int noinline bpf_fentry_test3(char a, int b, u64 c)
 132 {
 133         return a + b + c;
 134 }
 135
 136 int noinline bpf_fentry_test4(void *a, char b, int c, u64 d)
 137 {
 138         return (long)a + b + c + d;
 139 }
 140
 141 int noinline bpf_fentry_test5(u64 a, void *b, short c, int d, u64 e)
 142 {
 143         return a + (long)b + c + d + e;
 144 }
 145
 146 int noinline bpf_fentry_test6(u64 a, void *b, short c, int d, void *e, u64 f)
 147 {
 148         return a + (long)b + c + d + (long)e + f;
 149 }
 150
 151 struct bpf_fentry_test_t {
 152         struct bpf_fentry_test_t *a;
 153 };
 154
 155 int noinline bpf_fentry_test7(struct bpf_fentry_test_t *arg)
 156 {
 157         return (long)arg;
 158 }
 159
 160 int noinline bpf_fentry_test8(struct bpf_fentry_test_t *arg)
 161 {
 162         return (long)arg->a;
 163 }
 164
 165 int noinline bpf_modify_return_test(int a, int *b)
 166 {
 167         *b += 1;
 168         return a + *b;
 169 }
 170 __diag_pop();
 171
 172 ALLOW_ERROR_INJECTION(bpf_modify_return_test, ERRNO);
 173
 174 static void *bpf_test_init(const union bpf_attr *kattr, u32 size,
 175                            u32 headroom, u32 tailroom)
 176 {
 177         void __user *data_in = u64_to_user_ptr(kattr->test.data_in);
 178         u32 user_size = kattr->test.data_size_in;
 179         void *data;
 180
 181         if (size < ETH_HLEN || size > PAGE_SIZE - headroom - tailroom)
 182                 return ERR_PTR(-EINVAL);
 183
 184         if (user_size > size)
 185                 return ERR_PTR(-EMSGSIZE);
 186
 187         data = kzalloc(size + headroom + tailroom, GFP_USER);
 188         if (!data)
 189                 return ERR_PTR(-ENOMEM);
 190
 191         if (copy_from_user(data + headroom, data_in, user_size)) {
 192                 kfree(data);
 193                 return ERR_PTR(-EFAULT);
 194         }
 195
 196         return data;
 197 }
 198
 199 int bpf_prog_test_run_tracing(struct bpf_prog *prog,
 200                               const union bpf_attr *kattr,
 201                               union bpf_attr __user *uattr)
 202 {
 203         struct bpf_fentry_test_t arg = {};
 204         u16 side_effect = 0, ret = 0;
 205         int b = 2, err = -EFAULT;
 206         u32 retval = 0;
 207
 208         if (kattr->test.flags || kattr->test.cpu)
 209                 return -EINVAL;
 210
 211         switch (prog->expected_attach_type) {
 212         case BPF_TRACE_FENTRY:
 213         case BPF_TRACE_FEXIT:
 214                 if (bpf_fentry_test1(1) != 2 ||
 215                     bpf_fentry_test2(2, 3) != 5 ||
 216                     bpf_fentry_test3(4, 5, 6) != 15 ||
 217                     bpf_fentry_test4((void *)7, 8, 9, 10) != 34 ||
 218                     bpf_fentry_test5(11, (void *)12, 13, 14, 15) != 65 ||
 219                     bpf_fentry_test6(16, (void *)17, 18, 19, (void *)20, 21) != 111 ||
 220                     bpf_fentry_test7((struct bpf_fentry_test_t *)0) != 0 ||
 221                     bpf_fentry_test8(&arg) != 0)
 222                         goto out;
 223                 break;
 224         case BPF_MODIFY_RETURN:
 225                 ret = bpf_modify_return_test(1, &b);
 226                 if (b != 2)
 227                         side_effect = 1;
 228                 break;
 229         default:
 230                 goto out;
 231         }
 232
 233         retval = ((u32)side_effect << 16) | ret;
 234         if (copy_to_user(&uattr->test.retval, &retval, sizeof(retval)))
 235                 goto out;
 236
 237         err = 0;
 238 out:
 239         trace_bpf_test_finish(&err);
 240         return err;
 241 }
 242
 243 struct bpf_raw_tp_test_run_info {
 244         struct bpf_prog *prog;
 245         void *ctx;
 246         u32 retval;
 247 };
 248
 249 static void
 250 __bpf_prog_test_run_raw_tp(void *data)
 251 {
 252         struct bpf_raw_tp_test_run_info *info = data;
 253
 254         rcu_read_lock();
 255         info->retval = BPF_PROG_RUN(info->prog, info->ctx);
 256         rcu_read_unlock();
 257 }
 258
 259 int bpf_prog_test_run_raw_tp(struct bpf_prog *prog,
 260                              const union bpf_attr *kattr,
 261                              union bpf_attr __user *uattr)
 262 {
 263         void __user *ctx_in = u64_to_user_ptr(kattr->test.ctx_in);
 264         __u32 ctx_size_in = kattr->test.ctx_size_in;
 265         struct bpf_raw_tp_test_run_info info;
 266         int cpu = kattr->test.cpu, err = 0;
 267         int current_cpu;
 268
 269         /* doesn't support data_in/out, ctx_out, duration, or repeat */
 270         if (kattr->test.data_in || kattr->test.data_out ||
 271             kattr->test.ctx_out || kattr->test.duration ||
 272             kattr->test.repeat)
 273                 return -EINVAL;
 274
 275         if (ctx_size_in < prog->aux->max_ctx_offset ||
 276             ctx_size_in > MAX_BPF_FUNC_ARGS * sizeof(u64))
 277                 return -EINVAL;
 278
 279         if ((kattr->test.flags & BPF_F_TEST_RUN_ON_CPU) == 0 && cpu != 0)
 280                 return -EINVAL;
 281
 282         if (ctx_size_in) {
 283                 info.ctx = kzalloc(ctx_size_in, GFP_USER);
 284                 if (!info.ctx)
 285                         return -ENOMEM;
 286                 if (copy_from_user(info.ctx, ctx_in, ctx_size_in)) {
 287                         err = -EFAULT;
 288                         goto out;
 289                 }
 290         } else {
 291                 info.ctx = NULL;
 292         }
 293
 294         info.prog = prog;
 295
 296         current_cpu = get_cpu();
 297         if ((kattr->test.flags & BPF_F_TEST_RUN_ON_CPU) == 0 ||
 298             cpu == current_cpu) {
 299                 __bpf_prog_test_run_raw_tp(&info);
 300         } else if (cpu >= nr_cpu_ids || !cpu_online(cpu)) {
 301                 /* smp_call_function_single() also checks cpu_online()
 302                  * after csd_lock(). However, since cpu is from user
 303                  * space, let's do an extra quick check to filter out
 304                  * invalid value before smp_call_function_single().
 305                  */
 306                 err = -ENXIO;
 307         } else {
 308                 err = smp_call_function_single(cpu, __bpf_prog_test_run_raw_tp,
 309                                                &info, 1);
 310         }
 311         put_cpu();
 312
 313         if (!err &&
 314             copy_to_user(&uattr->test.retval, &info.retval, sizeof(u32)))
 315                 err = -EFAULT;
 316
 317 out:
 318         kfree(info.ctx);
 319         return err;
 320 }
 321
 322 static void *bpf_ctx_init(const union bpf_attr *kattr, u32 max_size)
 323 {
 324         void __user *data_in = u64_to_user_ptr(kattr->test.ctx_in);
 325         void __user *data_out = u64_to_user_ptr(kattr->test.ctx_out);
 326         u32 size = kattr->test.ctx_size_in;
 327         void *data;
 328         int err;
 329
 330         if (!data_in && !data_out)
 331                 return NULL;
 332
 333         data = kzalloc(max_size, GFP_USER);
 334         if (!data)
 335                 return ERR_PTR(-ENOMEM);
 336
 337         if (data_in) {
 338                 err = bpf_check_uarg_tail_zero(data_in, max_size, size);
 339                 if (err) {
 340                         kfree(data);
 341                         return ERR_PTR(err);
 342                 }
 343
 344                 size = min_t(u32, max_size, size);
 345                 if (copy_from_user(data, data_in, size)) {
 346                         kfree(data);
 347                         return ERR_PTR(-EFAULT);
 348                 }
 349         }
 350         return data;
 351 }
 352
 353 static int bpf_ctx_finish(const union bpf_attr *kattr,
 354                           union bpf_attr __user *uattr, const void *data,
 355                           u32 size)
 356 {
 357         void __user *data_out = u64_to_user_ptr(kattr->test.ctx_out);
 358         int err = -EFAULT;
 359         u32 copy_size = size;
 360
 361         if (!data || !data_out)
 362                 return 0;
 363
 364         if (copy_size > kattr->test.ctx_size_out) {
 365                 copy_size = kattr->test.ctx_size_out;
 366                 err = -ENOSPC;
 367         }
 368
 369         if (copy_to_user(data_out, data, copy_size))
 370                 goto out;
 371         if (copy_to_user(&uattr->test.ctx_size_out, &size, sizeof(size)))
 372                 goto out;
 373         if (err != -ENOSPC)
 374                 err = 0;
 375 out:
 376         return err;
 377 }
 378
 379 /**
 380  * range_is_zero - test whether buffer is initialized
 381  * @buf: buffer to check
 382  * @from: check from this position
 383  * @to: check up until (excluding) this position
 384  *
 385  * This function returns true if the there is a non-zero byte
 386  * in the buf in the range [from,to).
 387  */
 388 static inline bool range_is_zero(void *buf, size_t from, size_t to)
 389 {
 390         return !memchr_inv((u8 *)buf + from, 0, to - from);
 391 }
 392
 393 static int convert___skb_to_skb(struct sk_buff *skb, struct __sk_buff *__skb)
 394 {
 395         struct qdisc_skb_cb *cb = (struct qdisc_skb_cb *)skb->cb;
 396
 397         if (!__skb)
 398                 return 0;
 399
 400         /* make sure the fields we don't use are zeroed */
 401         if (!range_is_zero(__skb, 0, offsetof(struct __sk_buff, mark)))
 402                 return -EINVAL;
 403
 404         /* mark is allowed */
 405
 406         if (!range_is_zero(__skb, offsetofend(struct __sk_buff, mark),
 407                            offsetof(struct __sk_buff, priority)))
 408                 return -EINVAL;
 409
 410         /* priority is allowed */
 411
 412         if (!range_is_zero(__skb, offsetofend(struct __sk_buff, priority),
 413                            offsetof(struct __sk_buff, ifindex)))
 414                 return -EINVAL;
 415
 416         /* ifindex is allowed */
 417
 418         if (!range_is_zero(__skb, offsetofend(struct __sk_buff, ifindex),
 419                            offsetof(struct __sk_buff, cb)))
 420                 return -EINVAL;
 421
 422         /* cb is allowed */
 423
 424         if (!range_is_zero(__skb, offsetofend(struct __sk_buff, cb),
 425                            offsetof(struct __sk_buff, tstamp)))
 426                 return -EINVAL;
 427
 428         /* tstamp is allowed */
 429         /* wire_len is allowed */
 430         /* gso_segs is allowed */
 431
 432         if (!range_is_zero(__skb, offsetofend(struct __sk_buff, gso_segs),
 433                            offsetof(struct __sk_buff, gso_size)))
 434                 return -EINVAL;
 435
 436         /* gso_size is allowed */
 437
 438         if (!range_is_zero(__skb, offsetofend(struct __sk_buff, gso_size),
 439                            sizeof(struct __sk_buff)))
 440                 return -EINVAL;
 441
 442         skb->mark = __skb->mark;
 443         skb->priority = __skb->priority;
 444         skb->tstamp = __skb->tstamp;
 445         memcpy(&cb->data, __skb->cb, QDISC_CB_PRIV_LEN);
 446
 447         if (__skb->wire_len == 0) {
 448                 cb->pkt_len = skb->len;
 449         } else {
 450                 if (__skb->wire_len < skb->len ||
 451                     __skb->wire_len > GSO_MAX_SIZE)
 452                         return -EINVAL;
 453                 cb->pkt_len = __skb->wire_len;
 454         }
 455
 456         if (__skb->gso_segs > GSO_MAX_SEGS)
 457                 return -EINVAL;
 458         skb_shinfo(skb)->gso_segs = __skb->gso_segs;
 459         skb_shinfo(skb)->gso_size = __skb->gso_size;
 460
 461         return 0;
 462 }
 463
 464 static void convert_skb_to___skb(struct sk_buff *skb, struct __sk_buff *__skb)
 465 {
 466         struct qdisc_skb_cb *cb = (struct qdisc_skb_cb *)skb->cb;
 467
 468         if (!__skb)
 469                 return;
 470
 471         __skb->mark = skb->mark;
 472         __skb->priority = skb->priority;
 473         __skb->ifindex = skb->dev->ifindex;
 474         __skb->tstamp = skb->tstamp;
 475         memcpy(__skb->cb, &cb->data, QDISC_CB_PRIV_LEN);
 476         __skb->wire_len = cb->pkt_len;
 477         __skb->gso_segs = skb_shinfo(skb)->gso_segs;
 478 }
 479
 480 int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr,
 481                           union bpf_attr __user *uattr)
 482 {
 483         bool is_l2 = false, is_direct_pkt_access = false;
 484         struct net *net = current->nsproxy->net_ns;
 485         struct net_device *dev = net->loopback_dev;
 486         u32 size = kattr->test.data_size_in;
 487         u32 repeat = kattr->test.repeat;
 488         struct __sk_buff *ctx = NULL;
 489         u32 retval, duration;
 490         int hh_len = ETH_HLEN;
 491         struct sk_buff *skb;
 492         struct sock *sk;
 493         void *data;
 494         int ret;
 495
 496         if (kattr->test.flags || kattr->test.cpu)
 497                 return -EINVAL;
 498
 499         data = bpf_test_init(kattr, size, NET_SKB_PAD + NET_IP_ALIGN,
 500                              SKB_DATA_ALIGN(sizeof(struct skb_shared_info)));
 501         if (IS_ERR(data))
 502                 return PTR_ERR(data);
 503
 504         ctx = bpf_ctx_init(kattr, sizeof(struct __sk_buff));
 505         if (IS_ERR(ctx)) {
 506                 kfree(data);
 507                 return PTR_ERR(ctx);
 508         }
 509
 510         switch (prog->type) {
 511         case BPF_PROG_TYPE_SCHED_CLS:
 512         case BPF_PROG_TYPE_SCHED_ACT:
 513                 is_l2 = true;
 514                 fallthrough;
 515         case BPF_PROG_TYPE_LWT_IN:
 516         case BPF_PROG_TYPE_LWT_OUT:
 517         case BPF_PROG_TYPE_LWT_XMIT:
 518                 is_direct_pkt_access = true;
 519                 break;
 520         default:
 521                 break;
 522         }
 523
 524         sk = kzalloc(sizeof(struct sock), GFP_USER);
 525         if (!sk) {
 526                 kfree(data);
 527                 kfree(ctx);
 528                 return -ENOMEM;
 529         }
 530         sock_net_set(sk, net);
 531         sock_init_data(NULL, sk);
 532
 533         skb = build_skb(data, 0);
 534         if (!skb) {
 535                 kfree(data);
 536                 kfree(ctx);
 537                 kfree(sk);
 538                 return -ENOMEM;
 539         }
 540         skb->sk = sk;
 541
 542         skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN);
 543         __skb_put(skb, size);
 544         if (ctx && ctx->ifindex > 1) {
 545                 dev = dev_get_by_index(net, ctx->ifindex);
 546                 if (!dev) {
 547                         ret = -ENODEV;
 548                         goto out;
 549                 }
 550         }
 551         skb->protocol = eth_type_trans(skb, dev);
 552         skb_reset_network_header(skb);
 553
 554         switch (skb->protocol) {
 555         case htons(ETH_P_IP):
 556                 sk->sk_family = AF_INET;
 557                 if (sizeof(struct iphdr) <= skb_headlen(skb)) {
 558                         sk->sk_rcv_saddr = ip_hdr(skb)->saddr;
 559                         sk->sk_daddr = ip_hdr(skb)->daddr;
 560                 }
 561                 break;
 562 #if IS_ENABLED(CONFIG_IPV6)
 563         case htons(ETH_P_IPV6):
 564                 sk->sk_family = AF_INET6;
 565                 if (sizeof(struct ipv6hdr) <= skb_headlen(skb)) {
 566                         sk->sk_v6_rcv_saddr = ipv6_hdr(skb)->saddr;
 567                         sk->sk_v6_daddr = ipv6_hdr(skb)->daddr;
 568                 }
 569                 break;
 570 #endif
 571         default:
 572                 break;
 573         }
 574
 575         if (is_l2)
 576                 __skb_push(skb, hh_len);
 577         if (is_direct_pkt_access)
 578                 bpf_compute_data_pointers(skb);
 579         ret = convert___skb_to_skb(skb, ctx);
 580         if (ret)
 581                 goto out;
 582         ret = bpf_test_run(prog, skb, repeat, &retval, &duration, false);
 583         if (ret)
 584                 goto out;
 585         if (!is_l2) {
 586                 if (skb_headroom(skb) < hh_len) {
 587                         int nhead = HH_DATA_ALIGN(hh_len - skb_headroom(skb));
 588
 589                         if (pskb_expand_head(skb, nhead, 0, GFP_USER)) {
 590                                 ret = -ENOMEM;
 591                                 goto out;
 592                         }
 593                 }
 594                 memset(__skb_push(skb, hh_len), 0, hh_len);
 595         }
 596         convert_skb_to___skb(skb, ctx);
 597
 598         size = skb->len;
 599         /* bpf program can never convert linear skb to non-linear */
 600         if (WARN_ON_ONCE(skb_is_nonlinear(skb)))
 601                 size = skb_headlen(skb);
 602         ret = bpf_test_finish(kattr, uattr, skb->data, size, retval, duration);
 603         if (!ret)
 604                 ret = bpf_ctx_finish(kattr, uattr, ctx,
 605                                      sizeof(struct __sk_buff));
 606 out:
 607         if (dev && dev != net->loopback_dev)
 608                 dev_put(dev);
 609         kfree_skb(skb);
 610         bpf_sk_storage_free(sk);
 611         kfree(sk);
 612         kfree(ctx);
 613         return ret;
 614 }
 615
 616 int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr,
 617                           union bpf_attr __user *uattr)
 618 {
 619         u32 tailroom = SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
 620         u32 headroom = XDP_PACKET_HEADROOM;
 621         u32 size = kattr->test.data_size_in;
 622         u32 repeat = kattr->test.repeat;
 623         struct netdev_rx_queue *rxqueue;
 624         struct xdp_buff xdp = {};
 625         u32 retval, duration;
 626         u32 max_data_sz;
 627         void *data;
 628         int ret;
 629
 630         if (kattr->test.ctx_in || kattr->test.ctx_out)
 631                 return -EINVAL;
 632
 633         /* XDP have extra tailroom as (most) drivers use full page */
 634         max_data_sz = 4096 - headroom - tailroom;
 635
 636         data = bpf_test_init(kattr, max_data_sz, headroom, tailroom);
 637         if (IS_ERR(data))
 638                 return PTR_ERR(data);
 639
 640         xdp.data_hard_start = data;
 641         xdp.data = data + headroom;
 642         xdp.data_meta = xdp.data;
 643         xdp.data_end = xdp.data + size;
 644         xdp.frame_sz = headroom + max_data_sz + tailroom;
 645
 646         rxqueue = __netif_get_rx_queue(current->nsproxy->net_ns->loopback_dev, 0);
 647         xdp.rxq = &rxqueue->xdp_rxq;
 648         bpf_prog_change_xdp(NULL, prog);
 649         ret = bpf_test_run(prog, &xdp, repeat, &retval, &duration, true);
 650         if (ret)
 651                 goto out;
 652         if (xdp.data != data + headroom || xdp.data_end != xdp.data + size)
 653                 size = xdp.data_end - xdp.data;
 654         ret = bpf_test_finish(kattr, uattr, xdp.data, size, retval, duration);
 655 out:
 656         bpf_prog_change_xdp(prog, NULL);
 657         kfree(data);
 658         return ret;
 659 }
 660
 661 static int verify_user_bpf_flow_keys(struct bpf_flow_keys *ctx)
 662 {
 663         /* make sure the fields we don't use are zeroed */
 664         if (!range_is_zero(ctx, 0, offsetof(struct bpf_flow_keys, flags)))
 665                 return -EINVAL;
 666
 667         /* flags is allowed */
 668
 669         if (!range_is_zero(ctx, offsetofend(struct bpf_flow_keys, flags),
 670                            sizeof(struct bpf_flow_keys)))
 671                 return -EINVAL;
 672
 673         return 0;
 674 }
 675
 676 int bpf_prog_test_run_flow_dissector(struct bpf_prog *prog,
 677                                      const union bpf_attr *kattr,
 678                                      union bpf_attr __user *uattr)
 679 {
 680         u32 size = kattr->test.data_size_in;
 681         struct bpf_flow_dissector ctx = {};
 682         u32 repeat = kattr->test.repeat;
 683         struct bpf_flow_keys *user_ctx;
 684         struct bpf_flow_keys flow_keys;
 685         u64 time_start, time_spent = 0;
 686         const struct ethhdr *eth;
 687         unsigned int flags = 0;
 688         u32 retval, duration;
 689         void *data;
 690         int ret;
 691         u32 i;
 692
 693         if (prog->type != BPF_PROG_TYPE_FLOW_DISSECTOR)
 694                 return -EINVAL;
 695
 696         if (kattr->test.flags || kattr->test.cpu)
 697                 return -EINVAL;
 698
 699         if (size < ETH_HLEN)
 700                 return -EINVAL;
 701
 702         data = bpf_test_init(kattr, size, 0, 0);
 703         if (IS_ERR(data))
 704                 return PTR_ERR(data);
 705
 706         eth = (struct ethhdr *)data;
 707
 708         if (!repeat)
 709                 repeat = 1;
 710
 711         user_ctx = bpf_ctx_init(kattr, sizeof(struct bpf_flow_keys));
 712         if (IS_ERR(user_ctx)) {
 713                 kfree(data);
 714                 return PTR_ERR(user_ctx);
 715         }
 716         if (user_ctx) {
 717                 ret = verify_user_bpf_flow_keys(user_ctx);
 718                 if (ret)
 719                         goto out;
 720                 flags = user_ctx->flags;
 721         }
 722
 723         ctx.flow_keys = &flow_keys;
 724         ctx.data = data;
 725         ctx.data_end = (__u8 *)data + size;
 726
 727         rcu_read_lock();
 728         preempt_disable();
 729         time_start = ktime_get_ns();
 730         for (i = 0; i < repeat; i++) {
 731                 retval = bpf_flow_dissect(prog, &ctx, eth->h_proto, ETH_HLEN,
 732                                           size, flags);
 733
 734                 if (signal_pending(current)) {
 735                         preempt_enable();
 736                         rcu_read_unlock();
 737
 738                         ret = -EINTR;
 739                         goto out;
 740                 }
 741
 742                 if (need_resched()) {
 743                         time_spent += ktime_get_ns() - time_start;
 744                         preempt_enable();
 745                         rcu_read_unlock();
 746
 747                         cond_resched();
 748
 749                         rcu_read_lock();
 750                         preempt_disable();
 751                         time_start = ktime_get_ns();
 752                 }
 753         }
 754         time_spent += ktime_get_ns() - time_start;
 755         preempt_enable();
 756         rcu_read_unlock();
 757
 758         do_div(time_spent, repeat);
 759         duration = time_spent > U32_MAX ? U32_MAX : (u32)time_spent;
 760
 761         ret = bpf_test_finish(kattr, uattr, &flow_keys, sizeof(flow_keys),
 762                               retval, duration);
 763         if (!ret)
 764                 ret = bpf_ctx_finish(kattr, uattr, user_ctx,
 765                                      sizeof(struct bpf_flow_keys));
 766
 767 out:
 768         kfree(user_ctx);
 769         kfree(data);
 770         return ret;
 771 }