include/linux/filter.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Linux Socket Filter Data Structures
   4  */
   5 #ifndef __LINUX_FILTER_H__
   6 #define __LINUX_FILTER_H__
   7
   8 #include <linux/atomic.h>
   9 #include <linux/bpf.h>
  10 #include <linux/refcount.h>
  11 #include <linux/compat.h>
  12 #include <linux/skbuff.h>
  13 #include <linux/linkage.h>
  14 #include <linux/printk.h>
  15 #include <linux/workqueue.h>
  16 #include <linux/sched.h>
  17 #include <linux/sched/clock.h>
  18 #include <linux/capability.h>
  19 #include <linux/set_memory.h>
  20 #include <linux/kallsyms.h>
  21 #include <linux/if_vlan.h>
  22 #include <linux/vmalloc.h>
  23 #include <linux/sockptr.h>
  24 #include <crypto/sha1.h>
  25 #include <linux/u64_stats_sync.h>
  26
  27 #include <net/sch_generic.h>
  28
  29 #include <asm/byteorder.h>
  30 #include <uapi/linux/filter.h>
  31
  32 struct sk_buff;
  33 struct sock;
  34 struct seccomp_data;
  35 struct bpf_prog_aux;
  36 struct xdp_rxq_info;
  37 struct xdp_buff;
  38 struct sock_reuseport;
  39 struct ctl_table;
  40 struct ctl_table_header;
  41
  42 /* ArgX, context and stack frame pointer register positions. Note,
  43  * Arg1, Arg2, Arg3, etc are used as argument mappings of function
  44  * calls in BPF_CALL instruction.
  45  */
  46 #define BPF_REG_ARG1    BPF_REG_1
  47 #define BPF_REG_ARG2    BPF_REG_2
  48 #define BPF_REG_ARG3    BPF_REG_3
  49 #define BPF_REG_ARG4    BPF_REG_4
  50 #define BPF_REG_ARG5    BPF_REG_5
  51 #define BPF_REG_CTX     BPF_REG_6
  52 #define BPF_REG_FP      BPF_REG_10
  53
  54 /* Additional register mappings for converted user programs. */
  55 #define BPF_REG_A       BPF_REG_0
  56 #define BPF_REG_X       BPF_REG_7
  57 #define BPF_REG_TMP     BPF_REG_2       /* scratch reg */
  58 #define BPF_REG_D       BPF_REG_8       /* data, callee-saved */
  59 #define BPF_REG_H       BPF_REG_9       /* hlen, callee-saved */
  60
  61 /* Kernel hidden auxiliary/helper register. */
  62 #define BPF_REG_AX              MAX_BPF_REG
  63 #define MAX_BPF_EXT_REG         (MAX_BPF_REG + 1)
  64 #define MAX_BPF_JIT_REG         MAX_BPF_EXT_REG
  65
  66 /* unused opcode to mark special call to bpf_tail_call() helper */
  67 #define BPF_TAIL_CALL   0xf0
  68
  69 /* unused opcode to mark special load instruction. Same as BPF_ABS */
  70 #define BPF_PROBE_MEM   0x20
  71
  72 /* unused opcode to mark special ldsx instruction. Same as BPF_IND */
  73 #define BPF_PROBE_MEMSX 0x40
  74
  75 /* unused opcode to mark special load instruction. Same as BPF_MSH */
  76 #define BPF_PROBE_MEM32 0xa0
  77
  78 /* unused opcode to mark special atomic instruction */
  79 #define BPF_PROBE_ATOMIC 0xe0
  80
  81 /* unused opcode to mark call to interpreter with arguments */
  82 #define BPF_CALL_ARGS   0xe0
  83
  84 /* unused opcode to mark speculation barrier for mitigating
  85  * Speculative Store Bypass
  86  */
  87 #define BPF_NOSPEC      0xc0
  88
  89 /* As per nm, we expose JITed images as text (code) section for
  90  * kallsyms. That way, tools like perf can find it to match
  91  * addresses.
  92  */
  93 #define BPF_SYM_ELF_TYPE        't'
  94
  95 /* BPF program can access up to 512 bytes of stack space. */
  96 #define MAX_BPF_STACK   512
  97
  98 /* Helper macros for filter block array initializers. */
  99
 100 /* ALU ops on registers, bpf_add|sub|...: dst_reg += src_reg */
 101
 102 #define BPF_ALU64_REG_OFF(OP, DST, SRC, OFF)                    \
 103         ((struct bpf_insn) {                                    \
 104                 .code  = BPF_ALU64 | BPF_OP(OP) | BPF_X,        \
 105                 .dst_reg = DST,                                 \
 106                 .src_reg = SRC,                                 \
 107                 .off   = OFF,                                   \
 108                 .imm   = 0 })
 109
 110 #define BPF_ALU64_REG(OP, DST, SRC)                             \
 111         BPF_ALU64_REG_OFF(OP, DST, SRC, 0)
 112
 113 #define BPF_ALU32_REG_OFF(OP, DST, SRC, OFF)                    \
 114         ((struct bpf_insn) {                                    \
 115                 .code  = BPF_ALU | BPF_OP(OP) | BPF_X,          \
 116                 .dst_reg = DST,                                 \
 117                 .src_reg = SRC,                                 \
 118                 .off   = OFF,                                   \
 119                 .imm   = 0 })
 120
 121 #define BPF_ALU32_REG(OP, DST, SRC)                             \
 122         BPF_ALU32_REG_OFF(OP, DST, SRC, 0)
 123
 124 /* ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 */
 125
 126 #define BPF_ALU64_IMM_OFF(OP, DST, IMM, OFF)                    \
 127         ((struct bpf_insn) {                                    \
 128                 .code  = BPF_ALU64 | BPF_OP(OP) | BPF_K,        \
 129                 .dst_reg = DST,                                 \
 130                 .src_reg = 0,                                   \
 131                 .off   = OFF,                                   \
 132                 .imm   = IMM })
 133 #define BPF_ALU64_IMM(OP, DST, IMM)                             \
 134         BPF_ALU64_IMM_OFF(OP, DST, IMM, 0)
 135
 136 #define BPF_ALU32_IMM_OFF(OP, DST, IMM, OFF)                    \
 137         ((struct bpf_insn) {                                    \
 138                 .code  = BPF_ALU | BPF_OP(OP) | BPF_K,          \
 139                 .dst_reg = DST,                                 \
 140                 .src_reg = 0,                                   \
 141                 .off   = OFF,                                   \
 142                 .imm   = IMM })
 143 #define BPF_ALU32_IMM(OP, DST, IMM)                             \
 144         BPF_ALU32_IMM_OFF(OP, DST, IMM, 0)
 145
 146 /* Endianess conversion, cpu_to_{l,b}e(), {l,b}e_to_cpu() */
 147
 148 #define BPF_ENDIAN(TYPE, DST, LEN)                              \
 149         ((struct bpf_insn) {                                    \
 150                 .code  = BPF_ALU | BPF_END | BPF_SRC(TYPE),     \
 151                 .dst_reg = DST,                                 \
 152                 .src_reg = 0,                                   \
 153                 .off   = 0,                                     \
 154                 .imm   = LEN })
 155
 156 /* Byte Swap, bswap16/32/64 */
 157
 158 #define BPF_BSWAP(DST, LEN)                                     \
 159         ((struct bpf_insn) {                                    \
 160                 .code  = BPF_ALU64 | BPF_END | BPF_SRC(BPF_TO_LE),      \
 161                 .dst_reg = DST,                                 \
 162                 .src_reg = 0,                                   \
 163                 .off   = 0,                                     \
 164                 .imm   = LEN })
 165
 166 /* Short form of mov, dst_reg = src_reg */
 167
 168 #define BPF_MOV64_REG(DST, SRC)                                 \
 169         ((struct bpf_insn) {                                    \
 170                 .code  = BPF_ALU64 | BPF_MOV | BPF_X,           \
 171                 .dst_reg = DST,                                 \
 172                 .src_reg = SRC,                                 \
 173                 .off   = 0,                                     \
 174                 .imm   = 0 })
 175
 176 #define BPF_MOV32_REG(DST, SRC)                                 \
 177         ((struct bpf_insn) {                                    \
 178                 .code  = BPF_ALU | BPF_MOV | BPF_X,             \
 179                 .dst_reg = DST,                                 \
 180                 .src_reg = SRC,                                 \
 181                 .off   = 0,                                     \
 182                 .imm   = 0 })
 183
 184 /* Special (internal-only) form of mov, used to resolve per-CPU addrs:
 185  * dst_reg = src_reg + <percpu_base_off>
 186  * BPF_ADDR_PERCPU is used as a special insn->off value.
 187  */
 188 #define BPF_ADDR_PERCPU (-1)
 189
 190 #define BPF_MOV64_PERCPU_REG(DST, SRC)                          \
 191         ((struct bpf_insn) {                                    \
 192                 .code  = BPF_ALU64 | BPF_MOV | BPF_X,           \
 193                 .dst_reg = DST,                                 \
 194                 .src_reg = SRC,                                 \
 195                 .off   = BPF_ADDR_PERCPU,                       \
 196                 .imm   = 0 })
 197
 198 static inline bool insn_is_mov_percpu_addr(const struct bpf_insn *insn)
 199 {
 200         return insn->code == (BPF_ALU64 | BPF_MOV | BPF_X) && insn->off == BPF_ADDR_PERCPU;
 201 }
 202
 203 /* Short form of mov, dst_reg = imm32 */
 204
 205 #define BPF_MOV64_IMM(DST, IMM)                                 \
 206         ((struct bpf_insn) {                                    \
 207                 .code  = BPF_ALU64 | BPF_MOV | BPF_K,           \
 208                 .dst_reg = DST,                                 \
 209                 .src_reg = 0,                                   \
 210                 .off   = 0,                                     \
 211                 .imm   = IMM })
 212
 213 #define BPF_MOV32_IMM(DST, IMM)                                 \
 214         ((struct bpf_insn) {                                    \
 215                 .code  = BPF_ALU | BPF_MOV | BPF_K,             \
 216                 .dst_reg = DST,                                 \
 217                 .src_reg = 0,                                   \
 218                 .off   = 0,                                     \
 219                 .imm   = IMM })
 220
 221 /* Short form of movsx, dst_reg = (s8,s16,s32)src_reg */
 222
 223 #define BPF_MOVSX64_REG(DST, SRC, OFF)                          \
 224         ((struct bpf_insn) {                                    \
 225                 .code  = BPF_ALU64 | BPF_MOV | BPF_X,           \
 226                 .dst_reg = DST,                                 \
 227                 .src_reg = SRC,                                 \
 228                 .off   = OFF,                                   \
 229                 .imm   = 0 })
 230
 231 #define BPF_MOVSX32_REG(DST, SRC, OFF)                          \
 232         ((struct bpf_insn) {                                    \
 233                 .code  = BPF_ALU | BPF_MOV | BPF_X,             \
 234                 .dst_reg = DST,                                 \
 235                 .src_reg = SRC,                                 \
 236                 .off   = OFF,                                   \
 237                 .imm   = 0 })
 238
 239 /* Special form of mov32, used for doing explicit zero extension on dst. */
 240 #define BPF_ZEXT_REG(DST)                                       \
 241         ((struct bpf_insn) {                                    \
 242                 .code  = BPF_ALU | BPF_MOV | BPF_X,             \
 243                 .dst_reg = DST,                                 \
 244                 .src_reg = DST,                                 \
 245                 .off   = 0,                                     \
 246                 .imm   = 1 })
 247
 248 static inline bool insn_is_zext(const struct bpf_insn *insn)
 249 {
 250         return insn->code == (BPF_ALU | BPF_MOV | BPF_X) && insn->imm == 1;
 251 }
 252
 253 /* addr_space_cast from as(0) to as(1) is for converting bpf arena pointers
 254  * to pointers in user vma.
 255  */
 256 static inline bool insn_is_cast_user(const struct bpf_insn *insn)
 257 {
 258         return insn->code == (BPF_ALU64 | BPF_MOV | BPF_X) &&
 259                               insn->off == BPF_ADDR_SPACE_CAST &&
 260                               insn->imm == 1U << 16;
 261 }
 262
 263 /* BPF_LD_IMM64 macro encodes single 'load 64-bit immediate' insn */
 264 #define BPF_LD_IMM64(DST, IMM)                                  \
 265         BPF_LD_IMM64_RAW(DST, 0, IMM)
 266
 267 #define BPF_LD_IMM64_RAW(DST, SRC, IMM)                         \
 268         ((struct bpf_insn) {                                    \
 269                 .code  = BPF_LD | BPF_DW | BPF_IMM,             \
 270                 .dst_reg = DST,                                 \
 271                 .src_reg = SRC,                                 \
 272                 .off   = 0,                                     \
 273                 .imm   = (__u32) (IMM) }),                      \
 274         ((struct bpf_insn) {                                    \
 275                 .code  = 0, /* zero is reserved opcode */       \
 276                 .dst_reg = 0,                                   \
 277                 .src_reg = 0,                                   \
 278                 .off   = 0,                                     \
 279                 .imm   = ((__u64) (IMM)) >> 32 })
 280
 281 /* pseudo BPF_LD_IMM64 insn used to refer to process-local map_fd */
 282 #define BPF_LD_MAP_FD(DST, MAP_FD)                              \
 283         BPF_LD_IMM64_RAW(DST, BPF_PSEUDO_MAP_FD, MAP_FD)
 284
 285 /* Short form of mov based on type, BPF_X: dst_reg = src_reg, BPF_K: dst_reg = imm32 */
 286
 287 #define BPF_MOV64_RAW(TYPE, DST, SRC, IMM)                      \
 288         ((struct bpf_insn) {                                    \
 289                 .code  = BPF_ALU64 | BPF_MOV | BPF_SRC(TYPE),   \
 290                 .dst_reg = DST,                                 \
 291                 .src_reg = SRC,                                 \
 292                 .off   = 0,                                     \
 293                 .imm   = IMM })
 294
 295 #define BPF_MOV32_RAW(TYPE, DST, SRC, IMM)                      \
 296         ((struct bpf_insn) {                                    \
 297                 .code  = BPF_ALU | BPF_MOV | BPF_SRC(TYPE),     \
 298                 .dst_reg = DST,                                 \
 299                 .src_reg = SRC,                                 \
 300                 .off   = 0,                                     \
 301                 .imm   = IMM })
 302
 303 /* Direct packet access, R0 = *(uint *) (skb->data + imm32) */
 304
 305 #define BPF_LD_ABS(SIZE, IMM)                                   \
 306         ((struct bpf_insn) {                                    \
 307                 .code  = BPF_LD | BPF_SIZE(SIZE) | BPF_ABS,     \
 308                 .dst_reg = 0,                                   \
 309                 .src_reg = 0,                                   \
 310                 .off   = 0,                                     \
 311                 .imm   = IMM })
 312
 313 /* Indirect packet access, R0 = *(uint *) (skb->data + src_reg + imm32) */
 314
 315 #define BPF_LD_IND(SIZE, SRC, IMM)                              \
 316         ((struct bpf_insn) {                                    \
 317                 .code  = BPF_LD | BPF_SIZE(SIZE) | BPF_IND,     \
 318                 .dst_reg = 0,                                   \
 319                 .src_reg = SRC,                                 \
 320                 .off   = 0,                                     \
 321                 .imm   = IMM })
 322
 323 /* Memory load, dst_reg = *(uint *) (src_reg + off16) */
 324
 325 #define BPF_LDX_MEM(SIZE, DST, SRC, OFF)                        \
 326         ((struct bpf_insn) {                                    \
 327                 .code  = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEM,    \
 328                 .dst_reg = DST,                                 \
 329                 .src_reg = SRC,                                 \
 330                 .off   = OFF,                                   \
 331                 .imm   = 0 })
 332
 333 /* Memory load, dst_reg = *(signed size *) (src_reg + off16) */
 334
 335 #define BPF_LDX_MEMSX(SIZE, DST, SRC, OFF)                      \
 336         ((struct bpf_insn) {                                    \
 337                 .code  = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEMSX,  \
 338                 .dst_reg = DST,                                 \
 339                 .src_reg = SRC,                                 \
 340                 .off   = OFF,                                   \
 341                 .imm   = 0 })
 342
 343 /* Memory store, *(uint *) (dst_reg + off16) = src_reg */
 344
 345 #define BPF_STX_MEM(SIZE, DST, SRC, OFF)                        \
 346         ((struct bpf_insn) {                                    \
 347                 .code  = BPF_STX | BPF_SIZE(SIZE) | BPF_MEM,    \
 348                 .dst_reg = DST,                                 \
 349                 .src_reg = SRC,                                 \
 350                 .off   = OFF,                                   \
 351                 .imm   = 0 })
 352
 353
 354 /*
 355  * Atomic operations:
 356  *
 357  *   BPF_ADD                  *(uint *) (dst_reg + off16) += src_reg
 358  *   BPF_AND                  *(uint *) (dst_reg + off16) &= src_reg
 359  *   BPF_OR                   *(uint *) (dst_reg + off16) |= src_reg
 360  *   BPF_XOR                  *(uint *) (dst_reg + off16) ^= src_reg
 361  *   BPF_ADD | BPF_FETCH      src_reg = atomic_fetch_add(dst_reg + off16, src_reg);
 362  *   BPF_AND | BPF_FETCH      src_reg = atomic_fetch_and(dst_reg + off16, src_reg);
 363  *   BPF_OR | BPF_FETCH       src_reg = atomic_fetch_or(dst_reg + off16, src_reg);
 364  *   BPF_XOR | BPF_FETCH      src_reg = atomic_fetch_xor(dst_reg + off16, src_reg);
 365  *   BPF_XCHG                 src_reg = atomic_xchg(dst_reg + off16, src_reg)
 366  *   BPF_CMPXCHG              r0 = atomic_cmpxchg(dst_reg + off16, r0, src_reg)
 367  */
 368
 369 #define BPF_ATOMIC_OP(SIZE, OP, DST, SRC, OFF)                  \
 370         ((struct bpf_insn) {                                    \
 371                 .code  = BPF_STX | BPF_SIZE(SIZE) | BPF_ATOMIC, \
 372                 .dst_reg = DST,                                 \
 373                 .src_reg = SRC,                                 \
 374                 .off   = OFF,                                   \
 375                 .imm   = OP })
 376
 377 /* Legacy alias */
 378 #define BPF_STX_XADD(SIZE, DST, SRC, OFF) BPF_ATOMIC_OP(SIZE, BPF_ADD, DST, SRC, OFF)
 379
 380 /* Memory store, *(uint *) (dst_reg + off16) = imm32 */
 381
 382 #define BPF_ST_MEM(SIZE, DST, OFF, IMM)                         \
 383         ((struct bpf_insn) {                                    \
 384                 .code  = BPF_ST | BPF_SIZE(SIZE) | BPF_MEM,     \
 385                 .dst_reg = DST,                                 \
 386                 .src_reg = 0,                                   \
 387                 .off   = OFF,                                   \
 388                 .imm   = IMM })
 389
 390 /* Conditional jumps against registers, if (dst_reg 'op' src_reg) goto pc + off16 */
 391
 392 #define BPF_JMP_REG(OP, DST, SRC, OFF)                          \
 393         ((struct bpf_insn) {                                    \
 394                 .code  = BPF_JMP | BPF_OP(OP) | BPF_X,          \
 395                 .dst_reg = DST,                                 \
 396                 .src_reg = SRC,                                 \
 397                 .off   = OFF,                                   \
 398                 .imm   = 0 })
 399
 400 /* Conditional jumps against immediates, if (dst_reg 'op' imm32) goto pc + off16 */
 401
 402 #define BPF_JMP_IMM(OP, DST, IMM, OFF)                          \
 403         ((struct bpf_insn) {                                    \
 404                 .code  = BPF_JMP | BPF_OP(OP) | BPF_K,          \
 405                 .dst_reg = DST,                                 \
 406                 .src_reg = 0,                                   \
 407                 .off   = OFF,                                   \
 408                 .imm   = IMM })
 409
 410 /* Like BPF_JMP_REG, but with 32-bit wide operands for comparison. */
 411
 412 #define BPF_JMP32_REG(OP, DST, SRC, OFF)                        \
 413         ((struct bpf_insn) {                                    \
 414                 .code  = BPF_JMP32 | BPF_OP(OP) | BPF_X,        \
 415                 .dst_reg = DST,                                 \
 416                 .src_reg = SRC,                                 \
 417                 .off   = OFF,                                   \
 418                 .imm   = 0 })
 419
 420 /* Like BPF_JMP_IMM, but with 32-bit wide operands for comparison. */
 421
 422 #define BPF_JMP32_IMM(OP, DST, IMM, OFF)                        \
 423         ((struct bpf_insn) {                                    \
 424                 .code  = BPF_JMP32 | BPF_OP(OP) | BPF_K,        \
 425                 .dst_reg = DST,                                 \
 426                 .src_reg = 0,                                   \
 427                 .off   = OFF,                                   \
 428                 .imm   = IMM })
 429
 430 /* Unconditional jumps, goto pc + off16 */
 431
 432 #define BPF_JMP_A(OFF)                                          \
 433         ((struct bpf_insn) {                                    \
 434                 .code  = BPF_JMP | BPF_JA,                      \
 435                 .dst_reg = 0,                                   \
 436                 .src_reg = 0,                                   \
 437                 .off   = OFF,                                   \
 438                 .imm   = 0 })
 439
 440 /* Relative call */
 441
 442 #define BPF_CALL_REL(TGT)                                       \
 443         ((struct bpf_insn) {                                    \
 444                 .code  = BPF_JMP | BPF_CALL,                    \
 445                 .dst_reg = 0,                                   \
 446                 .src_reg = BPF_PSEUDO_CALL,                     \
 447                 .off   = 0,                                     \
 448                 .imm   = TGT })
 449
 450 /* Convert function address to BPF immediate */
 451
 452 #define BPF_CALL_IMM(x) ((void *)(x) - (void *)__bpf_call_base)
 453
 454 #define BPF_EMIT_CALL(FUNC)                                     \
 455         ((struct bpf_insn) {                                    \
 456                 .code  = BPF_JMP | BPF_CALL,                    \
 457                 .dst_reg = 0,                                   \
 458                 .src_reg = 0,                                   \
 459                 .off   = 0,                                     \
 460                 .imm   = BPF_CALL_IMM(FUNC) })
 461
 462 /* Raw code statement block */
 463
 464 #define BPF_RAW_INSN(CODE, DST, SRC, OFF, IMM)                  \
 465         ((struct bpf_insn) {                                    \
 466                 .code  = CODE,                                  \
 467                 .dst_reg = DST,                                 \
 468                 .src_reg = SRC,                                 \
 469                 .off   = OFF,                                   \
 470                 .imm   = IMM })
 471
 472 /* Program exit */
 473
 474 #define BPF_EXIT_INSN()                                         \
 475         ((struct bpf_insn) {                                    \
 476                 .code  = BPF_JMP | BPF_EXIT,                    \
 477                 .dst_reg = 0,                                   \
 478                 .src_reg = 0,                                   \
 479                 .off   = 0,                                     \
 480                 .imm   = 0 })
 481
 482 /* Speculation barrier */
 483
 484 #define BPF_ST_NOSPEC()                                         \
 485         ((struct bpf_insn) {                                    \
 486                 .code  = BPF_ST | BPF_NOSPEC,                   \
 487                 .dst_reg = 0,                                   \
 488                 .src_reg = 0,                                   \
 489                 .off   = 0,                                     \
 490                 .imm   = 0 })
 491
 492 /* Internal classic blocks for direct assignment */
 493
 494 #define __BPF_STMT(CODE, K)                                     \
 495         ((struct sock_filter) BPF_STMT(CODE, K))
 496
 497 #define __BPF_JUMP(CODE, K, JT, JF)                             \
 498         ((struct sock_filter) BPF_JUMP(CODE, K, JT, JF))
 499
 500 #define bytes_to_bpf_size(bytes)                                \
 501 ({                                                              \
 502         int bpf_size = -EINVAL;                                 \
 503                                                                 \
 504         if (bytes == sizeof(u8))                                \
 505                 bpf_size = BPF_B;                               \
 506         else if (bytes == sizeof(u16))                          \
 507                 bpf_size = BPF_H;                               \
 508         else if (bytes == sizeof(u32))                          \
 509                 bpf_size = BPF_W;                               \
 510         else if (bytes == sizeof(u64))                          \
 511                 bpf_size = BPF_DW;                              \
 512                                                                 \
 513         bpf_size;                                               \
 514 })
 515
 516 #define bpf_size_to_bytes(bpf_size)                             \
 517 ({                                                              \
 518         int bytes = -EINVAL;                                    \
 519                                                                 \
 520         if (bpf_size == BPF_B)                                  \
 521                 bytes = sizeof(u8);                             \
 522         else if (bpf_size == BPF_H)                             \
 523                 bytes = sizeof(u16);                            \
 524         else if (bpf_size == BPF_W)                             \
 525                 bytes = sizeof(u32);                            \
 526         else if (bpf_size == BPF_DW)                            \
 527                 bytes = sizeof(u64);                            \
 528                                                                 \
 529         bytes;                                                  \
 530 })
 531
 532 #define BPF_SIZEOF(type)                                        \
 533         ({                                                      \
 534                 const int __size = bytes_to_bpf_size(sizeof(type)); \
 535                 BUILD_BUG_ON(__size < 0);                       \
 536                 __size;                                         \
 537         })
 538
 539 #define BPF_FIELD_SIZEOF(type, field)                           \
 540         ({                                                      \
 541                 const int __size = bytes_to_bpf_size(sizeof_field(type, field)); \
 542                 BUILD_BUG_ON(__size < 0);                       \
 543                 __size;                                         \
 544         })
 545
 546 #define BPF_LDST_BYTES(insn)                                    \
 547         ({                                                      \
 548                 const int __size = bpf_size_to_bytes(BPF_SIZE((insn)->code)); \
 549                 WARN_ON(__size < 0);                            \
 550                 __size;                                         \
 551         })
 552
 553 #define __BPF_MAP_0(m, v, ...) v
 554 #define __BPF_MAP_1(m, v, t, a, ...) m(t, a)
 555 #define __BPF_MAP_2(m, v, t, a, ...) m(t, a), __BPF_MAP_1(m, v, __VA_ARGS__)
 556 #define __BPF_MAP_3(m, v, t, a, ...) m(t, a), __BPF_MAP_2(m, v, __VA_ARGS__)
 557 #define __BPF_MAP_4(m, v, t, a, ...) m(t, a), __BPF_MAP_3(m, v, __VA_ARGS__)
 558 #define __BPF_MAP_5(m, v, t, a, ...) m(t, a), __BPF_MAP_4(m, v, __VA_ARGS__)
 559
 560 #define __BPF_REG_0(...) __BPF_PAD(5)
 561 #define __BPF_REG_1(...) __BPF_MAP(1, __VA_ARGS__), __BPF_PAD(4)
 562 #define __BPF_REG_2(...) __BPF_MAP(2, __VA_ARGS__), __BPF_PAD(3)
 563 #define __BPF_REG_3(...) __BPF_MAP(3, __VA_ARGS__), __BPF_PAD(2)
 564 #define __BPF_REG_4(...) __BPF_MAP(4, __VA_ARGS__), __BPF_PAD(1)
 565 #define __BPF_REG_5(...) __BPF_MAP(5, __VA_ARGS__)
 566
 567 #define __BPF_MAP(n, ...) __BPF_MAP_##n(__VA_ARGS__)
 568 #define __BPF_REG(n, ...) __BPF_REG_##n(__VA_ARGS__)
 569
 570 #define __BPF_CAST(t, a)                                                       \
 571         (__force t)                                                            \
 572         (__force                                                               \
 573          typeof(__builtin_choose_expr(sizeof(t) == sizeof(unsigned long),      \
 574                                       (unsigned long)0, (t)0))) a
 575 #define __BPF_V void
 576 #define __BPF_N
 577
 578 #define __BPF_DECL_ARGS(t, a) t   a
 579 #define __BPF_DECL_REGS(t, a) u64 a
 580
 581 #define __BPF_PAD(n)                                                           \
 582         __BPF_MAP(n, __BPF_DECL_ARGS, __BPF_N, u64, __ur_1, u64, __ur_2,       \
 583                   u64, __ur_3, u64, __ur_4, u64, __ur_5)
 584
 585 #define BPF_CALL_x(x, attr, name, ...)                                         \
 586         static __always_inline                                                 \
 587         u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__));   \
 588         typedef u64 (*btf_##name)(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__)); \
 589         attr u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__));    \
 590         attr u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__))     \
 591         {                                                                      \
 592                 return ((btf_##name)____##name)(__BPF_MAP(x,__BPF_CAST,__BPF_N,__VA_ARGS__));\
 593         }                                                                      \
 594         static __always_inline                                                 \
 595         u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__))
 596
 597 #define __NOATTR
 598 #define BPF_CALL_0(name, ...)   BPF_CALL_x(0, __NOATTR, name, __VA_ARGS__)
 599 #define BPF_CALL_1(name, ...)   BPF_CALL_x(1, __NOATTR, name, __VA_ARGS__)
 600 #define BPF_CALL_2(name, ...)   BPF_CALL_x(2, __NOATTR, name, __VA_ARGS__)
 601 #define BPF_CALL_3(name, ...)   BPF_CALL_x(3, __NOATTR, name, __VA_ARGS__)
 602 #define BPF_CALL_4(name, ...)   BPF_CALL_x(4, __NOATTR, name, __VA_ARGS__)
 603 #define BPF_CALL_5(name, ...)   BPF_CALL_x(5, __NOATTR, name, __VA_ARGS__)
 604
 605 #define NOTRACE_BPF_CALL_1(name, ...)   BPF_CALL_x(1, notrace, name, __VA_ARGS__)
 606
 607 #define bpf_ctx_range(TYPE, MEMBER)                                             \
 608         offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1
 609 #define bpf_ctx_range_till(TYPE, MEMBER1, MEMBER2)                              \
 610         offsetof(TYPE, MEMBER1) ... offsetofend(TYPE, MEMBER2) - 1
 611 #if BITS_PER_LONG == 64
 612 # define bpf_ctx_range_ptr(TYPE, MEMBER)                                        \
 613         offsetof(TYPE, MEMBER) ... offsetofend(TYPE, MEMBER) - 1
 614 #else
 615 # define bpf_ctx_range_ptr(TYPE, MEMBER)                                        \
 616         offsetof(TYPE, MEMBER) ... offsetof(TYPE, MEMBER) + 8 - 1
 617 #endif /* BITS_PER_LONG == 64 */
 618
 619 #define bpf_target_off(TYPE, MEMBER, SIZE, PTR_SIZE)                            \
 620         ({                                                                      \
 621                 BUILD_BUG_ON(sizeof_field(TYPE, MEMBER) != (SIZE));             \
 622                 *(PTR_SIZE) = (SIZE);                                           \
 623                 offsetof(TYPE, MEMBER);                                         \
 624         })
 625
 626 /* A struct sock_filter is architecture independent. */
 627 struct compat_sock_fprog {
 628         u16             len;
 629         compat_uptr_t   filter; /* struct sock_filter * */
 630 };
 631
 632 struct sock_fprog_kern {
 633         u16                     len;
 634         struct sock_filter      *filter;
 635 };
 636
 637 /* Some arches need doubleword alignment for their instructions and/or data */
 638 #define BPF_IMAGE_ALIGNMENT 8
 639
 640 struct bpf_binary_header {
 641         u32 size;
 642         u8 image[] __aligned(BPF_IMAGE_ALIGNMENT);
 643 };
 644
 645 struct bpf_prog_stats {
 646         u64_stats_t cnt;
 647         u64_stats_t nsecs;
 648         u64_stats_t misses;
 649         struct u64_stats_sync syncp;
 650 } __aligned(2 * sizeof(u64));
 651
 652 struct sk_filter {
 653         refcount_t      refcnt;
 654         struct rcu_head rcu;
 655         struct bpf_prog *prog;
 656 };
 657
 658 DECLARE_STATIC_KEY_FALSE(bpf_stats_enabled_key);
 659
 660 extern struct mutex nf_conn_btf_access_lock;
 661 extern int (*nfct_btf_struct_access)(struct bpf_verifier_log *log,
 662                                      const struct bpf_reg_state *reg,
 663                                      int off, int size);
 664
 665 typedef unsigned int (*bpf_dispatcher_fn)(const void *ctx,
 666                                           const struct bpf_insn *insnsi,
 667                                           unsigned int (*bpf_func)(const void *,
 668                                                                    const struct bpf_insn *));
 669
 670 static __always_inline u32 __bpf_prog_run(const struct bpf_prog *prog,
 671                                           const void *ctx,
 672                                           bpf_dispatcher_fn dfunc)
 673 {
 674         u32 ret;
 675
 676         cant_migrate();
 677         if (static_branch_unlikely(&bpf_stats_enabled_key)) {
 678                 struct bpf_prog_stats *stats;
 679                 u64 duration, start = sched_clock();
 680                 unsigned long flags;
 681
 682                 ret = dfunc(ctx, prog->insnsi, prog->bpf_func);
 683
 684                 duration = sched_clock() - start;
 685                 stats = this_cpu_ptr(prog->stats);
 686                 flags = u64_stats_update_begin_irqsave(&stats->syncp);
 687                 u64_stats_inc(&stats->cnt);
 688                 u64_stats_add(&stats->nsecs, duration);
 689                 u64_stats_update_end_irqrestore(&stats->syncp, flags);
 690         } else {
 691                 ret = dfunc(ctx, prog->insnsi, prog->bpf_func);
 692         }
 693         return ret;
 694 }
 695
 696 static __always_inline u32 bpf_prog_run(const struct bpf_prog *prog, const void *ctx)
 697 {
 698         return __bpf_prog_run(prog, ctx, bpf_dispatcher_nop_func);
 699 }
 700
 701 /*
 702  * Use in preemptible and therefore migratable context to make sure that
 703  * the execution of the BPF program runs on one CPU.
 704  *
 705  * This uses migrate_disable/enable() explicitly to document that the
 706  * invocation of a BPF program does not require reentrancy protection
 707  * against a BPF program which is invoked from a preempting task.
 708  */
 709 static inline u32 bpf_prog_run_pin_on_cpu(const struct bpf_prog *prog,
 710                                           const void *ctx)
 711 {
 712         u32 ret;
 713
 714         migrate_disable();
 715         ret = bpf_prog_run(prog, ctx);
 716         migrate_enable();
 717         return ret;
 718 }
 719
 720 #define BPF_SKB_CB_LEN QDISC_CB_PRIV_LEN
 721
 722 struct bpf_skb_data_end {
 723         struct qdisc_skb_cb qdisc_cb;
 724         void *data_meta;
 725         void *data_end;
 726 };
 727
 728 struct bpf_nh_params {
 729         u32 nh_family;
 730         union {
 731                 u32 ipv4_nh;
 732                 struct in6_addr ipv6_nh;
 733         };
 734 };
 735
 736 struct bpf_redirect_info {
 737         u64 tgt_index;
 738         void *tgt_value;
 739         struct bpf_map *map;
 740         u32 flags;
 741         u32 kern_flags;
 742         u32 map_id;
 743         enum bpf_map_type map_type;
 744         struct bpf_nh_params nh;
 745 };
 746
 747 DECLARE_PER_CPU(struct bpf_redirect_info, bpf_redirect_info);
 748
 749 /* flags for bpf_redirect_info kern_flags */
 750 #define BPF_RI_F_RF_NO_DIRECT   BIT(0)  /* no napi_direct on return_frame */
 751
 752 /* Compute the linear packet data range [data, data_end) which
 753  * will be accessed by various program types (cls_bpf, act_bpf,
 754  * lwt, ...). Subsystems allowing direct data access must (!)
 755  * ensure that cb[] area can be written to when BPF program is
 756  * invoked (otherwise cb[] save/restore is necessary).
 757  */
 758 static inline void bpf_compute_data_pointers(struct sk_buff *skb)
 759 {
 760         struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
 761
 762         BUILD_BUG_ON(sizeof(*cb) > sizeof_field(struct sk_buff, cb));
 763         cb->data_meta = skb->data - skb_metadata_len(skb);
 764         cb->data_end  = skb->data + skb_headlen(skb);
 765 }
 766
 767 /* Similar to bpf_compute_data_pointers(), except that save orginal
 768  * data in cb->data and cb->meta_data for restore.
 769  */
 770 static inline void bpf_compute_and_save_data_end(
 771         struct sk_buff *skb, void **saved_data_end)
 772 {
 773         struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
 774
 775         *saved_data_end = cb->data_end;
 776         cb->data_end  = skb->data + skb_headlen(skb);
 777 }
 778
 779 /* Restore data saved by bpf_compute_and_save_data_end(). */
 780 static inline void bpf_restore_data_end(
 781         struct sk_buff *skb, void *saved_data_end)
 782 {
 783         struct bpf_skb_data_end *cb = (struct bpf_skb_data_end *)skb->cb;
 784
 785         cb->data_end = saved_data_end;
 786 }
 787
 788 static inline u8 *bpf_skb_cb(const struct sk_buff *skb)
 789 {
 790         /* eBPF programs may read/write skb->cb[] area to transfer meta
 791          * data between tail calls. Since this also needs to work with
 792          * tc, that scratch memory is mapped to qdisc_skb_cb's data area.
 793          *
 794          * In some socket filter cases, the cb unfortunately needs to be
 795          * saved/restored so that protocol specific skb->cb[] data won't
 796          * be lost. In any case, due to unpriviledged eBPF programs
 797          * attached to sockets, we need to clear the bpf_skb_cb() area
 798          * to not leak previous contents to user space.
 799          */
 800         BUILD_BUG_ON(sizeof_field(struct __sk_buff, cb) != BPF_SKB_CB_LEN);
 801         BUILD_BUG_ON(sizeof_field(struct __sk_buff, cb) !=
 802                      sizeof_field(struct qdisc_skb_cb, data));
 803
 804         return qdisc_skb_cb(skb)->data;
 805 }
 806
 807 /* Must be invoked with migration disabled */
 808 static inline u32 __bpf_prog_run_save_cb(const struct bpf_prog *prog,
 809                                          const void *ctx)
 810 {
 811         const struct sk_buff *skb = ctx;
 812         u8 *cb_data = bpf_skb_cb(skb);
 813         u8 cb_saved[BPF_SKB_CB_LEN];
 814         u32 res;
 815
 816         if (unlikely(prog->cb_access)) {
 817                 memcpy(cb_saved, cb_data, sizeof(cb_saved));
 818                 memset(cb_data, 0, sizeof(cb_saved));
 819         }
 820
 821         res = bpf_prog_run(prog, skb);
 822
 823         if (unlikely(prog->cb_access))
 824                 memcpy(cb_data, cb_saved, sizeof(cb_saved));
 825
 826         return res;
 827 }
 828
 829 static inline u32 bpf_prog_run_save_cb(const struct bpf_prog *prog,
 830                                        struct sk_buff *skb)
 831 {
 832         u32 res;
 833
 834         migrate_disable();
 835         res = __bpf_prog_run_save_cb(prog, skb);
 836         migrate_enable();
 837         return res;
 838 }
 839
 840 static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog,
 841                                         struct sk_buff *skb)
 842 {
 843         u8 *cb_data = bpf_skb_cb(skb);
 844         u32 res;
 845
 846         if (unlikely(prog->cb_access))
 847                 memset(cb_data, 0, BPF_SKB_CB_LEN);
 848
 849         res = bpf_prog_run_pin_on_cpu(prog, skb);
 850         return res;
 851 }
 852
 853 DECLARE_BPF_DISPATCHER(xdp)
 854
 855 DECLARE_STATIC_KEY_FALSE(bpf_master_redirect_enabled_key);
 856
 857 u32 xdp_master_redirect(struct xdp_buff *xdp);
 858
 859 void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog);
 860
 861 static inline u32 bpf_prog_insn_size(const struct bpf_prog *prog)
 862 {
 863         return prog->len * sizeof(struct bpf_insn);
 864 }
 865
 866 static inline u32 bpf_prog_tag_scratch_size(const struct bpf_prog *prog)
 867 {
 868         return round_up(bpf_prog_insn_size(prog) +
 869                         sizeof(__be64) + 1, SHA1_BLOCK_SIZE);
 870 }
 871
 872 static inline unsigned int bpf_prog_size(unsigned int proglen)
 873 {
 874         return max(sizeof(struct bpf_prog),
 875                    offsetof(struct bpf_prog, insns[proglen]));
 876 }
 877
 878 static inline bool bpf_prog_was_classic(const struct bpf_prog *prog)
 879 {
 880         /* When classic BPF programs have been loaded and the arch
 881          * does not have a classic BPF JIT (anymore), they have been
 882          * converted via bpf_migrate_filter() to eBPF and thus always
 883          * have an unspec program type.
 884          */
 885         return prog->type == BPF_PROG_TYPE_UNSPEC;
 886 }
 887
 888 static inline u32 bpf_ctx_off_adjust_machine(u32 size)
 889 {
 890         const u32 size_machine = sizeof(unsigned long);
 891
 892         if (size > size_machine && size % size_machine == 0)
 893                 size = size_machine;
 894
 895         return size;
 896 }
 897
 898 static inline bool
 899 bpf_ctx_narrow_access_ok(u32 off, u32 size, u32 size_default)
 900 {
 901         return size <= size_default && (size & (size - 1)) == 0;
 902 }
 903
 904 static inline u8
 905 bpf_ctx_narrow_access_offset(u32 off, u32 size, u32 size_default)
 906 {
 907         u8 access_off = off & (size_default - 1);
 908
 909 #ifdef __LITTLE_ENDIAN
 910         return access_off;
 911 #else
 912         return size_default - (access_off + size);
 913 #endif
 914 }
 915
 916 #define bpf_ctx_wide_access_ok(off, size, type, field)                  \
 917         (size == sizeof(__u64) &&                                       \
 918         off >= offsetof(type, field) &&                                 \
 919         off + sizeof(__u64) <= offsetofend(type, field) &&              \
 920         off % sizeof(__u64) == 0)
 921
 922 #define bpf_classic_proglen(fprog) (fprog->len * sizeof(fprog->filter[0]))
 923
 924 static inline int __must_check bpf_prog_lock_ro(struct bpf_prog *fp)
 925 {
 926 #ifndef CONFIG_BPF_JIT_ALWAYS_ON
 927         if (!fp->jited) {
 928                 set_vm_flush_reset_perms(fp);
 929                 return set_memory_ro((unsigned long)fp, fp->pages);
 930         }
 931 #endif
 932         return 0;
 933 }
 934
 935 static inline int __must_check
 936 bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr)
 937 {
 938         set_vm_flush_reset_perms(hdr);
 939         return set_memory_rox((unsigned long)hdr, hdr->size >> PAGE_SHIFT);
 940 }
 941
 942 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap);
 943 static inline int sk_filter(struct sock *sk, struct sk_buff *skb)
 944 {
 945         return sk_filter_trim_cap(sk, skb, 1);
 946 }
 947
 948 struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err);
 949 void bpf_prog_free(struct bpf_prog *fp);
 950
 951 bool bpf_opcode_in_insntable(u8 code);
 952
 953 void bpf_prog_fill_jited_linfo(struct bpf_prog *prog,
 954                                const u32 *insn_to_jit_off);
 955 int bpf_prog_alloc_jited_linfo(struct bpf_prog *prog);
 956 void bpf_prog_jit_attempt_done(struct bpf_prog *prog);
 957
 958 struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags);
 959 struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flags);
 960 struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
 961                                   gfp_t gfp_extra_flags);
 962 void __bpf_prog_free(struct bpf_prog *fp);
 963
 964 static inline void bpf_prog_unlock_free(struct bpf_prog *fp)
 965 {
 966         __bpf_prog_free(fp);
 967 }
 968
 969 typedef int (*bpf_aux_classic_check_t)(struct sock_filter *filter,
 970                                        unsigned int flen);
 971
 972 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog);
 973 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
 974                               bpf_aux_classic_check_t trans, bool save_orig);
 975 void bpf_prog_destroy(struct bpf_prog *fp);
 976
 977 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk);
 978 int sk_attach_bpf(u32 ufd, struct sock *sk);
 979 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk);
 980 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk);
 981 void sk_reuseport_prog_free(struct bpf_prog *prog);
 982 int sk_detach_filter(struct sock *sk);
 983 int sk_get_filter(struct sock *sk, sockptr_t optval, unsigned int len);
 984
 985 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp);
 986 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp);
 987
 988 u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
 989 #define __bpf_call_base_args \
 990         ((u64 (*)(u64, u64, u64, u64, u64, const struct bpf_insn *)) \
 991          (void *)__bpf_call_base)
 992
 993 struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog);
 994 void bpf_jit_compile(struct bpf_prog *prog);
 995 bool bpf_jit_needs_zext(void);
 996 bool bpf_jit_inlines_helper_call(s32 imm);
 997 bool bpf_jit_supports_subprog_tailcalls(void);
 998 bool bpf_jit_supports_percpu_insn(void);
 999 bool bpf_jit_supports_kfunc_call(void);
1000 bool bpf_jit_supports_far_kfunc_call(void);
1001 bool bpf_jit_supports_exceptions(void);
1002 bool bpf_jit_supports_ptr_xchg(void);
1003 bool bpf_jit_supports_arena(void);
1004 bool bpf_jit_supports_insn(struct bpf_insn *insn, bool in_arena);
1005 u64 bpf_arch_uaddress_limit(void);
1006 void arch_bpf_stack_walk(bool (*consume_fn)(void *cookie, u64 ip, u64 sp, u64 bp), void *cookie);
1007 bool bpf_helper_changes_pkt_data(void *func);
1008
1009 static inline bool bpf_dump_raw_ok(const struct cred *cred)
1010 {
1011         /* Reconstruction of call-sites is dependent on kallsyms,
1012          * thus make dump the same restriction.
1013          */
1014         return kallsyms_show_value(cred);
1015 }
1016
1017 struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off,
1018                                        const struct bpf_insn *patch, u32 len);
1019 int bpf_remove_insns(struct bpf_prog *prog, u32 off, u32 cnt);
1020
1021 void bpf_clear_redirect_map(struct bpf_map *map);
1022
1023 static inline bool xdp_return_frame_no_direct(void)
1024 {
1025         struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
1026
1027         return ri->kern_flags & BPF_RI_F_RF_NO_DIRECT;
1028 }
1029
1030 static inline void xdp_set_return_frame_no_direct(void)
1031 {
1032         struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
1033
1034         ri->kern_flags |= BPF_RI_F_RF_NO_DIRECT;
1035 }
1036
1037 static inline void xdp_clear_return_frame_no_direct(void)
1038 {
1039         struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
1040
1041         ri->kern_flags &= ~BPF_RI_F_RF_NO_DIRECT;
1042 }
1043
1044 static inline int xdp_ok_fwd_dev(const struct net_device *fwd,
1045                                  unsigned int pktlen)
1046 {
1047         unsigned int len;
1048
1049         if (unlikely(!(fwd->flags & IFF_UP)))
1050                 return -ENETDOWN;
1051
1052         len = fwd->mtu + fwd->hard_header_len + VLAN_HLEN;
1053         if (pktlen > len)
1054                 return -EMSGSIZE;
1055
1056         return 0;
1057 }
1058
1059 /* The pair of xdp_do_redirect and xdp_do_flush MUST be called in the
1060  * same cpu context. Further for best results no more than a single map
1061  * for the do_redirect/do_flush pair should be used. This limitation is
1062  * because we only track one map and force a flush when the map changes.
1063  * This does not appear to be a real limitation for existing software.
1064  */
1065 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
1066                             struct xdp_buff *xdp, struct bpf_prog *prog);
1067 int xdp_do_redirect(struct net_device *dev,
1068                     struct xdp_buff *xdp,
1069                     struct bpf_prog *prog);
1070 int xdp_do_redirect_frame(struct net_device *dev,
1071                           struct xdp_buff *xdp,
1072                           struct xdp_frame *xdpf,
1073                           struct bpf_prog *prog);
1074 void xdp_do_flush(void);
1075
1076 void bpf_warn_invalid_xdp_action(struct net_device *dev, struct bpf_prog *prog, u32 act);
1077
1078 #ifdef CONFIG_INET
1079 struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
1080                                   struct bpf_prog *prog, struct sk_buff *skb,
1081                                   struct sock *migrating_sk,
1082                                   u32 hash);
1083 #else
1084 static inline struct sock *
1085 bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
1086                      struct bpf_prog *prog, struct sk_buff *skb,
1087                      struct sock *migrating_sk,
1088                      u32 hash)
1089 {
1090         return NULL;
1091 }
1092 #endif
1093
1094 #ifdef CONFIG_BPF_JIT
1095 extern int bpf_jit_enable;
1096 extern int bpf_jit_harden;
1097 extern int bpf_jit_kallsyms;
1098 extern long bpf_jit_limit;
1099 extern long bpf_jit_limit_max;
1100
1101 typedef void (*bpf_jit_fill_hole_t)(void *area, unsigned int size);
1102
1103 void bpf_jit_fill_hole_with_zero(void *area, unsigned int size);
1104
1105 struct bpf_binary_header *
1106 bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr,
1107                      unsigned int alignment,
1108                      bpf_jit_fill_hole_t bpf_fill_ill_insns);
1109 void bpf_jit_binary_free(struct bpf_binary_header *hdr);
1110 u64 bpf_jit_alloc_exec_limit(void);
1111 void *bpf_jit_alloc_exec(unsigned long size);
1112 void bpf_jit_free_exec(void *addr);
1113 void bpf_jit_free(struct bpf_prog *fp);
1114 struct bpf_binary_header *
1115 bpf_jit_binary_pack_hdr(const struct bpf_prog *fp);
1116
1117 void *bpf_prog_pack_alloc(u32 size, bpf_jit_fill_hole_t bpf_fill_ill_insns);
1118 void bpf_prog_pack_free(void *ptr, u32 size);
1119
1120 static inline bool bpf_prog_kallsyms_verify_off(const struct bpf_prog *fp)
1121 {
1122         return list_empty(&fp->aux->ksym.lnode) ||
1123                fp->aux->ksym.lnode.prev == LIST_POISON2;
1124 }
1125
1126 struct bpf_binary_header *
1127 bpf_jit_binary_pack_alloc(unsigned int proglen, u8 **ro_image,
1128                           unsigned int alignment,
1129                           struct bpf_binary_header **rw_hdr,
1130                           u8 **rw_image,
1131                           bpf_jit_fill_hole_t bpf_fill_ill_insns);
1132 int bpf_jit_binary_pack_finalize(struct bpf_prog *prog,
1133                                  struct bpf_binary_header *ro_header,
1134                                  struct bpf_binary_header *rw_header);
1135 void bpf_jit_binary_pack_free(struct bpf_binary_header *ro_header,
1136                               struct bpf_binary_header *rw_header);
1137
1138 int bpf_jit_add_poke_descriptor(struct bpf_prog *prog,
1139                                 struct bpf_jit_poke_descriptor *poke);
1140
1141 int bpf_jit_get_func_addr(const struct bpf_prog *prog,
1142                           const struct bpf_insn *insn, bool extra_pass,
1143                           u64 *func_addr, bool *func_addr_fixed);
1144
1145 struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *fp);
1146 void bpf_jit_prog_release_other(struct bpf_prog *fp, struct bpf_prog *fp_other);
1147
1148 static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen,
1149                                 u32 pass, void *image)
1150 {
1151         pr_err("flen=%u proglen=%u pass=%u image=%pK from=%s pid=%d\n", flen,
1152                proglen, pass, image, current->comm, task_pid_nr(current));
1153
1154         if (image)
1155                 print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET,
1156                                16, 1, image, proglen, false);
1157 }
1158
1159 static inline bool bpf_jit_is_ebpf(void)
1160 {
1161 # ifdef CONFIG_HAVE_EBPF_JIT
1162         return true;
1163 # else
1164         return false;
1165 # endif
1166 }
1167
1168 static inline bool ebpf_jit_enabled(void)
1169 {
1170         return bpf_jit_enable && bpf_jit_is_ebpf();
1171 }
1172
1173 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp)
1174 {
1175         return fp->jited && bpf_jit_is_ebpf();
1176 }
1177
1178 static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog)
1179 {
1180         /* These are the prerequisites, should someone ever have the
1181          * idea to call blinding outside of them, we make sure to
1182          * bail out.
1183          */
1184         if (!bpf_jit_is_ebpf())
1185                 return false;
1186         if (!prog->jit_requested)
1187                 return false;
1188         if (!bpf_jit_harden)
1189                 return false;
1190         if (bpf_jit_harden == 1 && bpf_token_capable(prog->aux->token, CAP_BPF))
1191                 return false;
1192
1193         return true;
1194 }
1195
1196 static inline bool bpf_jit_kallsyms_enabled(void)
1197 {
1198         /* There are a couple of corner cases where kallsyms should
1199          * not be enabled f.e. on hardening.
1200          */
1201         if (bpf_jit_harden)
1202                 return false;
1203         if (!bpf_jit_kallsyms)
1204                 return false;
1205         if (bpf_jit_kallsyms == 1)
1206                 return true;
1207
1208         return false;
1209 }
1210
1211 const char *__bpf_address_lookup(unsigned long addr, unsigned long *size,
1212                                  unsigned long *off, char *sym);
1213 bool is_bpf_text_address(unsigned long addr);
1214 int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
1215                     char *sym);
1216 struct bpf_prog *bpf_prog_ksym_find(unsigned long addr);
1217
1218 static inline const char *
1219 bpf_address_lookup(unsigned long addr, unsigned long *size,
1220                    unsigned long *off, char **modname, char *sym)
1221 {
1222         const char *ret = __bpf_address_lookup(addr, size, off, sym);
1223
1224         if (ret && modname)
1225                 *modname = NULL;
1226         return ret;
1227 }
1228
1229 void bpf_prog_kallsyms_add(struct bpf_prog *fp);
1230 void bpf_prog_kallsyms_del(struct bpf_prog *fp);
1231
1232 #else /* CONFIG_BPF_JIT */
1233
1234 static inline bool ebpf_jit_enabled(void)
1235 {
1236         return false;
1237 }
1238
1239 static inline bool bpf_jit_blinding_enabled(struct bpf_prog *prog)
1240 {
1241         return false;
1242 }
1243
1244 static inline bool bpf_prog_ebpf_jited(const struct bpf_prog *fp)
1245 {
1246         return false;
1247 }
1248
1249 static inline int
1250 bpf_jit_add_poke_descriptor(struct bpf_prog *prog,
1251                             struct bpf_jit_poke_descriptor *poke)
1252 {
1253         return -ENOTSUPP;
1254 }
1255
1256 static inline void bpf_jit_free(struct bpf_prog *fp)
1257 {
1258         bpf_prog_unlock_free(fp);
1259 }
1260
1261 static inline bool bpf_jit_kallsyms_enabled(void)
1262 {
1263         return false;
1264 }
1265
1266 static inline const char *
1267 __bpf_address_lookup(unsigned long addr, unsigned long *size,
1268                      unsigned long *off, char *sym)
1269 {
1270         return NULL;
1271 }
1272
1273 static inline bool is_bpf_text_address(unsigned long addr)
1274 {
1275         return false;
1276 }
1277
1278 static inline int bpf_get_kallsym(unsigned int symnum, unsigned long *value,
1279                                   char *type, char *sym)
1280 {
1281         return -ERANGE;
1282 }
1283
1284 static inline struct bpf_prog *bpf_prog_ksym_find(unsigned long addr)
1285 {
1286         return NULL;
1287 }
1288
1289 static inline const char *
1290 bpf_address_lookup(unsigned long addr, unsigned long *size,
1291                    unsigned long *off, char **modname, char *sym)
1292 {
1293         return NULL;
1294 }
1295
1296 static inline void bpf_prog_kallsyms_add(struct bpf_prog *fp)
1297 {
1298 }
1299
1300 static inline void bpf_prog_kallsyms_del(struct bpf_prog *fp)
1301 {
1302 }
1303
1304 #endif /* CONFIG_BPF_JIT */
1305
1306 void bpf_prog_kallsyms_del_all(struct bpf_prog *fp);
1307
1308 #define BPF_ANC         BIT(15)
1309
1310 static inline bool bpf_needs_clear_a(const struct sock_filter *first)
1311 {
1312         switch (first->code) {
1313         case BPF_RET | BPF_K:
1314         case BPF_LD | BPF_W | BPF_LEN:
1315                 return false;
1316
1317         case BPF_LD | BPF_W | BPF_ABS:
1318         case BPF_LD | BPF_H | BPF_ABS:
1319         case BPF_LD | BPF_B | BPF_ABS:
1320                 if (first->k == SKF_AD_OFF + SKF_AD_ALU_XOR_X)
1321                         return true;
1322                 return false;
1323
1324         default:
1325                 return true;
1326         }
1327 }
1328
1329 static inline u16 bpf_anc_helper(const struct sock_filter *ftest)
1330 {
1331         BUG_ON(ftest->code & BPF_ANC);
1332
1333         switch (ftest->code) {
1334         case BPF_LD | BPF_W | BPF_ABS:
1335         case BPF_LD | BPF_H | BPF_ABS:
1336         case BPF_LD | BPF_B | BPF_ABS:
1337 #define BPF_ANCILLARY(CODE)     case SKF_AD_OFF + SKF_AD_##CODE:        \
1338                                 return BPF_ANC | SKF_AD_##CODE
1339                 switch (ftest->k) {
1340                 BPF_ANCILLARY(PROTOCOL);
1341                 BPF_ANCILLARY(PKTTYPE);
1342                 BPF_ANCILLARY(IFINDEX);
1343                 BPF_ANCILLARY(NLATTR);
1344                 BPF_ANCILLARY(NLATTR_NEST);
1345                 BPF_ANCILLARY(MARK);
1346                 BPF_ANCILLARY(QUEUE);
1347                 BPF_ANCILLARY(HATYPE);
1348                 BPF_ANCILLARY(RXHASH);
1349                 BPF_ANCILLARY(CPU);
1350                 BPF_ANCILLARY(ALU_XOR_X);
1351                 BPF_ANCILLARY(VLAN_TAG);
1352                 BPF_ANCILLARY(VLAN_TAG_PRESENT);
1353                 BPF_ANCILLARY(PAY_OFFSET);
1354                 BPF_ANCILLARY(RANDOM);
1355                 BPF_ANCILLARY(VLAN_TPID);
1356                 }
1357                 fallthrough;
1358         default:
1359                 return ftest->code;
1360         }
1361 }
1362
1363 void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb,
1364                                            int k, unsigned int size);
1365
1366 static inline int bpf_tell_extensions(void)
1367 {
1368         return SKF_AD_MAX;
1369 }
1370
1371 struct bpf_sock_addr_kern {
1372         struct sock *sk;
1373         struct sockaddr *uaddr;
1374         /* Temporary "register" to make indirect stores to nested structures
1375          * defined above. We need three registers to make such a store, but
1376          * only two (src and dst) are available at convert_ctx_access time
1377          */
1378         u64 tmp_reg;
1379         void *t_ctx;    /* Attach type specific context. */
1380         u32 uaddrlen;
1381 };
1382
1383 struct bpf_sock_ops_kern {
1384         struct  sock *sk;
1385         union {
1386                 u32 args[4];
1387                 u32 reply;
1388                 u32 replylong[4];
1389         };
1390         struct sk_buff  *syn_skb;
1391         struct sk_buff  *skb;
1392         void    *skb_data_end;
1393         u8      op;
1394         u8      is_fullsock;
1395         u8      remaining_opt_len;
1396         u64     temp;                   /* temp and everything after is not
1397                                          * initialized to 0 before calling
1398                                          * the BPF program. New fields that
1399                                          * should be initialized to 0 should
1400                                          * be inserted before temp.
1401                                          * temp is scratch storage used by
1402                                          * sock_ops_convert_ctx_access
1403                                          * as temporary storage of a register.
1404                                          */
1405 };
1406
1407 struct bpf_sysctl_kern {
1408         struct ctl_table_header *head;
1409         struct ctl_table *table;
1410         void *cur_val;
1411         size_t cur_len;
1412         void *new_val;
1413         size_t new_len;
1414         int new_updated;
1415         int write;
1416         loff_t *ppos;
1417         /* Temporary "register" for indirect stores to ppos. */
1418         u64 tmp_reg;
1419 };
1420
1421 #define BPF_SOCKOPT_KERN_BUF_SIZE       32
1422 struct bpf_sockopt_buf {
1423         u8              data[BPF_SOCKOPT_KERN_BUF_SIZE];
1424 };
1425
1426 struct bpf_sockopt_kern {
1427         struct sock     *sk;
1428         u8              *optval;
1429         u8              *optval_end;
1430         s32             level;
1431         s32             optname;
1432         s32             optlen;
1433         /* for retval in struct bpf_cg_run_ctx */
1434         struct task_struct *current_task;
1435         /* Temporary "register" for indirect stores to ppos. */
1436         u64             tmp_reg;
1437 };
1438
1439 int copy_bpf_fprog_from_user(struct sock_fprog *dst, sockptr_t src, int len);
1440
1441 struct bpf_sk_lookup_kern {
1442         u16             family;
1443         u16             protocol;
1444         __be16          sport;
1445         u16             dport;
1446         struct {
1447                 __be32 saddr;
1448                 __be32 daddr;
1449         } v4;
1450         struct {
1451                 const struct in6_addr *saddr;
1452                 const struct in6_addr *daddr;
1453         } v6;
1454         struct sock     *selected_sk;
1455         u32             ingress_ifindex;
1456         bool            no_reuseport;
1457 };
1458
1459 extern struct static_key_false bpf_sk_lookup_enabled;
1460
1461 /* Runners for BPF_SK_LOOKUP programs to invoke on socket lookup.
1462  *
1463  * Allowed return values for a BPF SK_LOOKUP program are SK_PASS and
1464  * SK_DROP. Their meaning is as follows:
1465  *
1466  *  SK_PASS && ctx.selected_sk != NULL: use selected_sk as lookup result
1467  *  SK_PASS && ctx.selected_sk == NULL: continue to htable-based socket lookup
1468  *  SK_DROP                           : terminate lookup with -ECONNREFUSED
1469  *
1470  * This macro aggregates return values and selected sockets from
1471  * multiple BPF programs according to following rules in order:
1472  *
1473  *  1. If any program returned SK_PASS and a non-NULL ctx.selected_sk,
1474  *     macro result is SK_PASS and last ctx.selected_sk is used.
1475  *  2. If any program returned SK_DROP return value,
1476  *     macro result is SK_DROP.
1477  *  3. Otherwise result is SK_PASS and ctx.selected_sk is NULL.
1478  *
1479  * Caller must ensure that the prog array is non-NULL, and that the
1480  * array as well as the programs it contains remain valid.
1481  */
1482 #define BPF_PROG_SK_LOOKUP_RUN_ARRAY(array, ctx, func)                  \
1483         ({                                                              \
1484                 struct bpf_sk_lookup_kern *_ctx = &(ctx);               \
1485                 struct bpf_prog_array_item *_item;                      \
1486                 struct sock *_selected_sk = NULL;                       \
1487                 bool _no_reuseport = false;                             \
1488                 struct bpf_prog *_prog;                                 \
1489                 bool _all_pass = true;                                  \
1490                 u32 _ret;                                               \
1491                                                                         \
1492                 migrate_disable();                                      \
1493                 _item = &(array)->items[0];                             \
1494                 while ((_prog = READ_ONCE(_item->prog))) {              \
1495                         /* restore most recent selection */             \
1496                         _ctx->selected_sk = _selected_sk;               \
1497                         _ctx->no_reuseport = _no_reuseport;             \
1498                                                                         \
1499                         _ret = func(_prog, _ctx);                       \
1500                         if (_ret == SK_PASS && _ctx->selected_sk) {     \
1501                                 /* remember last non-NULL socket */     \
1502                                 _selected_sk = _ctx->selected_sk;       \
1503                                 _no_reuseport = _ctx->no_reuseport;     \
1504                         } else if (_ret == SK_DROP && _all_pass) {      \
1505                                 _all_pass = false;                      \
1506                         }                                               \
1507                         _item++;                                        \
1508                 }                                                       \
1509                 _ctx->selected_sk = _selected_sk;                       \
1510                 _ctx->no_reuseport = _no_reuseport;                     \
1511                 migrate_enable();                                       \
1512                 _all_pass || _selected_sk ? SK_PASS : SK_DROP;          \
1513          })
1514
1515 static inline bool bpf_sk_lookup_run_v4(struct net *net, int protocol,
1516                                         const __be32 saddr, const __be16 sport,
1517                                         const __be32 daddr, const u16 dport,
1518                                         const int ifindex, struct sock **psk)
1519 {
1520         struct bpf_prog_array *run_array;
1521         struct sock *selected_sk = NULL;
1522         bool no_reuseport = false;
1523
1524         rcu_read_lock();
1525         run_array = rcu_dereference(net->bpf.run_array[NETNS_BPF_SK_LOOKUP]);
1526         if (run_array) {
1527                 struct bpf_sk_lookup_kern ctx = {
1528                         .family         = AF_INET,
1529                         .protocol       = protocol,
1530                         .v4.saddr       = saddr,
1531                         .v4.daddr       = daddr,
1532                         .sport          = sport,
1533                         .dport          = dport,
1534                         .ingress_ifindex        = ifindex,
1535                 };
1536                 u32 act;
1537
1538                 act = BPF_PROG_SK_LOOKUP_RUN_ARRAY(run_array, ctx, bpf_prog_run);
1539                 if (act == SK_PASS) {
1540                         selected_sk = ctx.selected_sk;
1541                         no_reuseport = ctx.no_reuseport;
1542                 } else {
1543                         selected_sk = ERR_PTR(-ECONNREFUSED);
1544                 }
1545         }
1546         rcu_read_unlock();
1547         *psk = selected_sk;
1548         return no_reuseport;
1549 }
1550
1551 #if IS_ENABLED(CONFIG_IPV6)
1552 static inline bool bpf_sk_lookup_run_v6(struct net *net, int protocol,
1553                                         const struct in6_addr *saddr,
1554                                         const __be16 sport,
1555                                         const struct in6_addr *daddr,
1556                                         const u16 dport,
1557                                         const int ifindex, struct sock **psk)
1558 {
1559         struct bpf_prog_array *run_array;
1560         struct sock *selected_sk = NULL;
1561         bool no_reuseport = false;
1562
1563         rcu_read_lock();
1564         run_array = rcu_dereference(net->bpf.run_array[NETNS_BPF_SK_LOOKUP]);
1565         if (run_array) {
1566                 struct bpf_sk_lookup_kern ctx = {
1567                         .family         = AF_INET6,
1568                         .protocol       = protocol,
1569                         .v6.saddr       = saddr,
1570                         .v6.daddr       = daddr,
1571                         .sport          = sport,
1572                         .dport          = dport,
1573                         .ingress_ifindex        = ifindex,
1574                 };
1575                 u32 act;
1576
1577                 act = BPF_PROG_SK_LOOKUP_RUN_ARRAY(run_array, ctx, bpf_prog_run);
1578                 if (act == SK_PASS) {
1579                         selected_sk = ctx.selected_sk;
1580                         no_reuseport = ctx.no_reuseport;
1581                 } else {
1582                         selected_sk = ERR_PTR(-ECONNREFUSED);
1583                 }
1584         }
1585         rcu_read_unlock();
1586         *psk = selected_sk;
1587         return no_reuseport;
1588 }
1589 #endif /* IS_ENABLED(CONFIG_IPV6) */
1590
1591 static __always_inline long __bpf_xdp_redirect_map(struct bpf_map *map, u64 index,
1592                                                    u64 flags, const u64 flag_mask,
1593                                                    void *lookup_elem(struct bpf_map *map, u32 key))
1594 {
1595         struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
1596         const u64 action_mask = XDP_ABORTED | XDP_DROP | XDP_PASS | XDP_TX;
1597
1598         /* Lower bits of the flags are used as return code on lookup failure */
1599         if (unlikely(flags & ~(action_mask | flag_mask)))
1600                 return XDP_ABORTED;
1601
1602         ri->tgt_value = lookup_elem(map, index);
1603         if (unlikely(!ri->tgt_value) && !(flags & BPF_F_BROADCAST)) {
1604                 /* If the lookup fails we want to clear out the state in the
1605                  * redirect_info struct completely, so that if an eBPF program
1606                  * performs multiple lookups, the last one always takes
1607                  * precedence.
1608                  */
1609                 ri->map_id = INT_MAX; /* Valid map id idr range: [1,INT_MAX[ */
1610                 ri->map_type = BPF_MAP_TYPE_UNSPEC;
1611                 return flags & action_mask;
1612         }
1613
1614         ri->tgt_index = index;
1615         ri->map_id = map->id;
1616         ri->map_type = map->map_type;
1617
1618         if (flags & BPF_F_BROADCAST) {
1619                 WRITE_ONCE(ri->map, map);
1620                 ri->flags = flags;
1621         } else {
1622                 WRITE_ONCE(ri->map, NULL);
1623                 ri->flags = 0;
1624         }
1625
1626         return XDP_REDIRECT;
1627 }
1628
1629 #ifdef CONFIG_NET
1630 int __bpf_skb_load_bytes(const struct sk_buff *skb, u32 offset, void *to, u32 len);
1631 int __bpf_skb_store_bytes(struct sk_buff *skb, u32 offset, const void *from,
1632                           u32 len, u64 flags);
1633 int __bpf_xdp_load_bytes(struct xdp_buff *xdp, u32 offset, void *buf, u32 len);
1634 int __bpf_xdp_store_bytes(struct xdp_buff *xdp, u32 offset, void *buf, u32 len);
1635 void *bpf_xdp_pointer(struct xdp_buff *xdp, u32 offset, u32 len);
1636 void bpf_xdp_copy_buf(struct xdp_buff *xdp, unsigned long off,
1637                       void *buf, unsigned long len, bool flush);
1638 #else /* CONFIG_NET */
1639 static inline int __bpf_skb_load_bytes(const struct sk_buff *skb, u32 offset,
1640                                        void *to, u32 len)
1641 {
1642         return -EOPNOTSUPP;
1643 }
1644
1645 static inline int __bpf_skb_store_bytes(struct sk_buff *skb, u32 offset,
1646                                         const void *from, u32 len, u64 flags)
1647 {
1648         return -EOPNOTSUPP;
1649 }
1650
1651 static inline int __bpf_xdp_load_bytes(struct xdp_buff *xdp, u32 offset,
1652                                        void *buf, u32 len)
1653 {
1654         return -EOPNOTSUPP;
1655 }
1656
1657 static inline int __bpf_xdp_store_bytes(struct xdp_buff *xdp, u32 offset,
1658                                         void *buf, u32 len)
1659 {
1660         return -EOPNOTSUPP;
1661 }
1662
1663 static inline void *bpf_xdp_pointer(struct xdp_buff *xdp, u32 offset, u32 len)
1664 {
1665         return NULL;
1666 }
1667
1668 static inline void bpf_xdp_copy_buf(struct xdp_buff *xdp, unsigned long off, void *buf,
1669                                     unsigned long len, bool flush)
1670 {
1671 }
1672 #endif /* CONFIG_NET */
1673
1674 #endif /* __LINUX_FILTER_H__ */