| /* |
| * Linux Socket Filter - Kernel level socket filtering |
| * |
| * Based on the design of the Berkeley Packet Filter. The new |
| * internal format has been designed by PLUMgrid: |
| * |
| * Copyright (c) 2011 - 2014 PLUMgrid, http://plumgrid.com |
| * |
| * Authors: |
| * |
| * Jay Schulist <jschlst@samba.org> |
| * Alexei Starovoitov <ast@plumgrid.com> |
| * Daniel Borkmann <dborkman@redhat.com> |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version |
| * 2 of the License, or (at your option) any later version. |
| * |
| * Andi Kleen - Fix a few bad bugs and races. |
| * Kris Katterjohn - Added many additional checks in bpf_check_classic() |
| */ |
| #include <linux/filter.h> |
| #include <linux/skbuff.h> |
| #include <linux/vmalloc.h> |
| #include <asm/unaligned.h> |
| |
| /* Registers */ |
| #define BPF_R0 regs[BPF_REG_0] |
| #define BPF_R1 regs[BPF_REG_1] |
| #define BPF_R2 regs[BPF_REG_2] |
| #define BPF_R3 regs[BPF_REG_3] |
| #define BPF_R4 regs[BPF_REG_4] |
| #define BPF_R5 regs[BPF_REG_5] |
| #define BPF_R6 regs[BPF_REG_6] |
| #define BPF_R7 regs[BPF_REG_7] |
| #define BPF_R8 regs[BPF_REG_8] |
| #define BPF_R9 regs[BPF_REG_9] |
| #define BPF_R10 regs[BPF_REG_10] |
| |
| /* Named registers */ |
| #define DST regs[insn->dst_reg] |
| #define SRC regs[insn->src_reg] |
| #define FP regs[BPF_REG_FP] |
| #define ARG1 regs[BPF_REG_ARG1] |
| #define CTX regs[BPF_REG_CTX] |
| #define IMM insn->imm |
| |
| /* No hurry in this branch |
| * |
| * Exported for the bpf jit load helper. |
| */ |
| void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb, int k, unsigned int size) |
| { |
| u8 *ptr = NULL; |
| |
| if (k >= SKF_NET_OFF) |
| ptr = skb_network_header(skb) + k - SKF_NET_OFF; |
| else if (k >= SKF_LL_OFF) |
| ptr = skb_mac_header(skb) + k - SKF_LL_OFF; |
| if (ptr >= skb->head && ptr + size <= skb_tail_pointer(skb)) |
| return ptr; |
| |
| return NULL; |
| } |
| |
| struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags) |
| { |
| gfp_t gfp_flags = GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO | |
| gfp_extra_flags; |
| struct bpf_work_struct *ws; |
| struct bpf_prog *fp; |
| |
| size = round_up(size, PAGE_SIZE); |
| fp = __vmalloc(size, gfp_flags, PAGE_KERNEL); |
| if (fp == NULL) |
| return NULL; |
| |
| ws = kmalloc(sizeof(*ws), GFP_KERNEL | gfp_extra_flags); |
| if (ws == NULL) { |
| vfree(fp); |
| return NULL; |
| } |
| |
| fp->pages = size / PAGE_SIZE; |
| fp->work = ws; |
| |
| return fp; |
| } |
| EXPORT_SYMBOL_GPL(bpf_prog_alloc); |
| |
| struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size, |
| gfp_t gfp_extra_flags) |
| { |
| gfp_t gfp_flags = GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO | |
| gfp_extra_flags; |
| struct bpf_prog *fp; |
| |
| BUG_ON(fp_old == NULL); |
| |
| size = round_up(size, PAGE_SIZE); |
| if (size <= fp_old->pages * PAGE_SIZE) |
| return fp_old; |
| |
| fp = __vmalloc(size, gfp_flags, PAGE_KERNEL); |
| if (fp != NULL) { |
| memcpy(fp, fp_old, fp_old->pages * PAGE_SIZE); |
| fp->pages = size / PAGE_SIZE; |
| |
| /* We keep fp->work from fp_old around in the new |
| * reallocated structure. |
| */ |
| fp_old->work = NULL; |
| __bpf_prog_free(fp_old); |
| } |
| |
| return fp; |
| } |
| EXPORT_SYMBOL_GPL(bpf_prog_realloc); |
| |
| void __bpf_prog_free(struct bpf_prog *fp) |
| { |
| kfree(fp->work); |
| vfree(fp); |
| } |
| EXPORT_SYMBOL_GPL(__bpf_prog_free); |
| |
| /* Base function for offset calculation. Needs to go into .text section, |
| * therefore keeping it non-static as well; will also be used by JITs |
| * anyway later on, so do not let the compiler omit it. |
| */ |
| noinline u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) |
| { |
| return 0; |
| } |
| |
| /** |
| * __bpf_prog_run - run eBPF program on a given context |
| * @ctx: is the data we are operating on |
| * @insn: is the array of eBPF instructions |
| * |
| * Decode and execute eBPF instructions. |
| */ |
| static unsigned int __bpf_prog_run(void *ctx, const struct bpf_insn *insn) |
| { |
| u64 stack[MAX_BPF_STACK / sizeof(u64)]; |
| u64 regs[MAX_BPF_REG], tmp; |
| static const void *jumptable[256] = { |
| [0 ... 255] = &&default_label, |
| /* Now overwrite non-defaults ... */ |
| /* 32 bit ALU operations */ |
| [BPF_ALU | BPF_ADD | BPF_X] = &&ALU_ADD_X, |
| [BPF_ALU | BPF_ADD | BPF_K] = &&ALU_ADD_K, |
| [BPF_ALU | BPF_SUB | BPF_X] = &&ALU_SUB_X, |
| [BPF_ALU | BPF_SUB | BPF_K] = &&ALU_SUB_K, |
| [BPF_ALU | BPF_AND | BPF_X] = &&ALU_AND_X, |
| [BPF_ALU | BPF_AND | BPF_K] = &&ALU_AND_K, |
| [BPF_ALU | BPF_OR | BPF_X] = &&ALU_OR_X, |
| [BPF_ALU | BPF_OR | BPF_K] = &&ALU_OR_K, |
| [BPF_ALU | BPF_LSH | BPF_X] = &&ALU_LSH_X, |
| [BPF_ALU | BPF_LSH | BPF_K] = &&ALU_LSH_K, |
| [BPF_ALU | BPF_RSH | BPF_X] = &&ALU_RSH_X, |
| [BPF_ALU | BPF_RSH | BPF_K] = &&ALU_RSH_K, |
| [BPF_ALU | BPF_XOR | BPF_X] = &&ALU_XOR_X, |
| [BPF_ALU | BPF_XOR | BPF_K] = &&ALU_XOR_K, |
| [BPF_ALU | BPF_MUL | BPF_X] = &&ALU_MUL_X, |
| [BPF_ALU | BPF_MUL | BPF_K] = &&ALU_MUL_K, |
| [BPF_ALU | BPF_MOV | BPF_X] = &&ALU_MOV_X, |
| [BPF_ALU | BPF_MOV | BPF_K] = &&ALU_MOV_K, |
| [BPF_ALU | BPF_DIV | BPF_X] = &&ALU_DIV_X, |
| [BPF_ALU | BPF_DIV | BPF_K] = &&ALU_DIV_K, |
| [BPF_ALU | BPF_MOD | BPF_X] = &&ALU_MOD_X, |
| [BPF_ALU | BPF_MOD | BPF_K] = &&ALU_MOD_K, |
| [BPF_ALU | BPF_NEG] = &&ALU_NEG, |
| [BPF_ALU | BPF_END | BPF_TO_BE] = &&ALU_END_TO_BE, |
| [BPF_ALU | BPF_END | BPF_TO_LE] = &&ALU_END_TO_LE, |
| /* 64 bit ALU operations */ |
| [BPF_ALU64 | BPF_ADD | BPF_X] = &&ALU64_ADD_X, |
| [BPF_ALU64 | BPF_ADD | BPF_K] = &&ALU64_ADD_K, |
| [BPF_ALU64 | BPF_SUB | BPF_X] = &&ALU64_SUB_X, |
| [BPF_ALU64 | BPF_SUB | BPF_K] = &&ALU64_SUB_K, |
| [BPF_ALU64 | BPF_AND | BPF_X] = &&ALU64_AND_X, |
| [BPF_ALU64 | BPF_AND | BPF_K] = &&ALU64_AND_K, |
| [BPF_ALU64 | BPF_OR | BPF_X] = &&ALU64_OR_X, |
| [BPF_ALU64 | BPF_OR | BPF_K] = &&ALU64_OR_K, |
| [BPF_ALU64 | BPF_LSH | BPF_X] = &&ALU64_LSH_X, |
| [BPF_ALU64 | BPF_LSH | BPF_K] = &&ALU64_LSH_K, |
| [BPF_ALU64 | BPF_RSH | BPF_X] = &&ALU64_RSH_X, |
| [BPF_ALU64 | BPF_RSH | BPF_K] = &&ALU64_RSH_K, |
| [BPF_ALU64 | BPF_XOR | BPF_X] = &&ALU64_XOR_X, |
| [BPF_ALU64 | BPF_XOR | BPF_K] = &&ALU64_XOR_K, |
| [BPF_ALU64 | BPF_MUL | BPF_X] = &&ALU64_MUL_X, |
| [BPF_ALU64 | BPF_MUL | BPF_K] = &&ALU64_MUL_K, |
| [BPF_ALU64 | BPF_MOV | BPF_X] = &&ALU64_MOV_X, |
| [BPF_ALU64 | BPF_MOV | BPF_K] = &&ALU64_MOV_K, |
| [BPF_ALU64 | BPF_ARSH | BPF_X] = &&ALU64_ARSH_X, |
| [BPF_ALU64 | BPF_ARSH | BPF_K] = &&ALU64_ARSH_K, |
| [BPF_ALU64 | BPF_DIV | BPF_X] = &&ALU64_DIV_X, |
| [BPF_ALU64 | BPF_DIV | BPF_K] = &&ALU64_DIV_K, |
| [BPF_ALU64 | BPF_MOD | BPF_X] = &&ALU64_MOD_X, |
| [BPF_ALU64 | BPF_MOD | BPF_K] = &&ALU64_MOD_K, |
| [BPF_ALU64 | BPF_NEG] = &&ALU64_NEG, |
| /* Call instruction */ |
| [BPF_JMP | BPF_CALL] = &&JMP_CALL, |
| /* Jumps */ |
| [BPF_JMP | BPF_JA] = &&JMP_JA, |
| [BPF_JMP | BPF_JEQ | BPF_X] = &&JMP_JEQ_X, |
| [BPF_JMP | BPF_JEQ | BPF_K] = &&JMP_JEQ_K, |
| [BPF_JMP | BPF_JNE | BPF_X] = &&JMP_JNE_X, |
| [BPF_JMP | BPF_JNE | BPF_K] = &&JMP_JNE_K, |
| [BPF_JMP | BPF_JGT | BPF_X] = &&JMP_JGT_X, |
| [BPF_JMP | BPF_JGT | BPF_K] = &&JMP_JGT_K, |
| [BPF_JMP | BPF_JGE | BPF_X] = &&JMP_JGE_X, |
| [BPF_JMP | BPF_JGE | BPF_K] = &&JMP_JGE_K, |
| [BPF_JMP | BPF_JSGT | BPF_X] = &&JMP_JSGT_X, |
| [BPF_JMP | BPF_JSGT | BPF_K] = &&JMP_JSGT_K, |
| [BPF_JMP | BPF_JSGE | BPF_X] = &&JMP_JSGE_X, |
| [BPF_JMP | BPF_JSGE | BPF_K] = &&JMP_JSGE_K, |
| [BPF_JMP | BPF_JSET | BPF_X] = &&JMP_JSET_X, |
| [BPF_JMP | BPF_JSET | BPF_K] = &&JMP_JSET_K, |
| /* Program return */ |
| [BPF_JMP | BPF_EXIT] = &&JMP_EXIT, |
| /* Store instructions */ |
| [BPF_STX | BPF_MEM | BPF_B] = &&STX_MEM_B, |
| [BPF_STX | BPF_MEM | BPF_H] = &&STX_MEM_H, |
| [BPF_STX | BPF_MEM | BPF_W] = &&STX_MEM_W, |
| [BPF_STX | BPF_MEM | BPF_DW] = &&STX_MEM_DW, |
| [BPF_STX | BPF_XADD | BPF_W] = &&STX_XADD_W, |
| [BPF_STX | BPF_XADD | BPF_DW] = &&STX_XADD_DW, |
| [BPF_ST | BPF_MEM | BPF_B] = &&ST_MEM_B, |
| [BPF_ST | BPF_MEM | BPF_H] = &&ST_MEM_H, |
| [BPF_ST | BPF_MEM | BPF_W] = &&ST_MEM_W, |
| [BPF_ST | BPF_MEM | BPF_DW] = &&ST_MEM_DW, |
| /* Load instructions */ |
| [BPF_LDX | BPF_MEM | BPF_B] = &&LDX_MEM_B, |
| [BPF_LDX | BPF_MEM | BPF_H] = &&LDX_MEM_H, |
| [BPF_LDX | BPF_MEM | BPF_W] = &&LDX_MEM_W, |
| [BPF_LDX | BPF_MEM | BPF_DW] = &&LDX_MEM_DW, |
| [BPF_LD | BPF_ABS | BPF_W] = &&LD_ABS_W, |
| [BPF_LD | BPF_ABS | BPF_H] = &&LD_ABS_H, |
| [BPF_LD | BPF_ABS | BPF_B] = &&LD_ABS_B, |
| [BPF_LD | BPF_IND | BPF_W] = &&LD_IND_W, |
| [BPF_LD | BPF_IND | BPF_H] = &&LD_IND_H, |
| [BPF_LD | BPF_IND | BPF_B] = &&LD_IND_B, |
| [BPF_LD | BPF_IMM | BPF_DW] = &&LD_IMM_DW, |
| }; |
| void *ptr; |
| int off; |
| |
| #define CONT ({ insn++; goto select_insn; }) |
| #define CONT_JMP ({ insn++; goto select_insn; }) |
| |
| FP = (u64) (unsigned long) &stack[ARRAY_SIZE(stack)]; |
| ARG1 = (u64) (unsigned long) ctx; |
| |
| /* Registers used in classic BPF programs need to be reset first. */ |
| regs[BPF_REG_A] = 0; |
| regs[BPF_REG_X] = 0; |
| |
| select_insn: |
| goto *jumptable[insn->code]; |
| |
| /* ALU */ |
| #define ALU(OPCODE, OP) \ |
| ALU64_##OPCODE##_X: \ |
| DST = DST OP SRC; \ |
| CONT; \ |
| ALU_##OPCODE##_X: \ |
| DST = (u32) DST OP (u32) SRC; \ |
| CONT; \ |
| ALU64_##OPCODE##_K: \ |
| DST = DST OP IMM; \ |
| CONT; \ |
| ALU_##OPCODE##_K: \ |
| DST = (u32) DST OP (u32) IMM; \ |
| CONT; |
| |
| ALU(ADD, +) |
| ALU(SUB, -) |
| ALU(AND, &) |
| ALU(OR, |) |
| ALU(LSH, <<) |
| ALU(RSH, >>) |
| ALU(XOR, ^) |
| ALU(MUL, *) |
| #undef ALU |
| ALU_NEG: |
| DST = (u32) -DST; |
| CONT; |
| ALU64_NEG: |
| DST = -DST; |
| CONT; |
| ALU_MOV_X: |
| DST = (u32) SRC; |
| CONT; |
| ALU_MOV_K: |
| DST = (u32) IMM; |
| CONT; |
| ALU64_MOV_X: |
| DST = SRC; |
| CONT; |
| ALU64_MOV_K: |
| DST = IMM; |
| CONT; |
| LD_IMM_DW: |
| DST = (u64) (u32) insn[0].imm | ((u64) (u32) insn[1].imm) << 32; |
| insn++; |
| CONT; |
| ALU64_ARSH_X: |
| (*(s64 *) &DST) >>= SRC; |
| CONT; |
| ALU64_ARSH_K: |
| (*(s64 *) &DST) >>= IMM; |
| CONT; |
| ALU64_MOD_X: |
| if (unlikely(SRC == 0)) |
| return 0; |
| tmp = DST; |
| DST = do_div(tmp, SRC); |
| CONT; |
| ALU_MOD_X: |
| if (unlikely(SRC == 0)) |
| return 0; |
| tmp = (u32) DST; |
| DST = do_div(tmp, (u32) SRC); |
| CONT; |
| ALU64_MOD_K: |
| tmp = DST; |
| DST = do_div(tmp, IMM); |
| CONT; |
| ALU_MOD_K: |
| tmp = (u32) DST; |
| DST = do_div(tmp, (u32) IMM); |
| CONT; |
| ALU64_DIV_X: |
| if (unlikely(SRC == 0)) |
| return 0; |
| do_div(DST, SRC); |
| CONT; |
| ALU_DIV_X: |
| if (unlikely(SRC == 0)) |
| return 0; |
| tmp = (u32) DST; |
| do_div(tmp, (u32) SRC); |
| DST = (u32) tmp; |
| CONT; |
| ALU64_DIV_K: |
| do_div(DST, IMM); |
| CONT; |
| ALU_DIV_K: |
| tmp = (u32) DST; |
| do_div(tmp, (u32) IMM); |
| DST = (u32) tmp; |
| CONT; |
| ALU_END_TO_BE: |
| switch (IMM) { |
| case 16: |
| DST = (__force u16) cpu_to_be16(DST); |
| break; |
| case 32: |
| DST = (__force u32) cpu_to_be32(DST); |
| break; |
| case 64: |
| DST = (__force u64) cpu_to_be64(DST); |
| break; |
| } |
| CONT; |
| ALU_END_TO_LE: |
| switch (IMM) { |
| case 16: |
| DST = (__force u16) cpu_to_le16(DST); |
| break; |
| case 32: |
| DST = (__force u32) cpu_to_le32(DST); |
| break; |
| case 64: |
| DST = (__force u64) cpu_to_le64(DST); |
| break; |
| } |
| CONT; |
| |
| /* CALL */ |
| JMP_CALL: |
| /* Function call scratches BPF_R1-BPF_R5 registers, |
| * preserves BPF_R6-BPF_R9, and stores return value |
| * into BPF_R0. |
| */ |
| BPF_R0 = (__bpf_call_base + insn->imm)(BPF_R1, BPF_R2, BPF_R3, |
| BPF_R4, BPF_R5); |
| CONT; |
| |
| /* JMP */ |
| JMP_JA: |
| insn += insn->off; |
| CONT; |
| JMP_JEQ_X: |
| if (DST == SRC) { |
| insn += insn->off; |
| CONT_JMP; |
| } |
| CONT; |
| JMP_JEQ_K: |
| if (DST == IMM) { |
| insn += insn->off; |
| CONT_JMP; |
| } |
| CONT; |
| JMP_JNE_X: |
| if (DST != SRC) { |
| insn += insn->off; |
| CONT_JMP; |
| } |
| CONT; |
| JMP_JNE_K: |
| if (DST != IMM) { |
| insn += insn->off; |
| CONT_JMP; |
| } |
| CONT; |
| JMP_JGT_X: |
| if (DST > SRC) { |
| insn += insn->off; |
| CONT_JMP; |
| } |
| CONT; |
| JMP_JGT_K: |
| if (DST > IMM) { |
| insn += insn->off; |
| CONT_JMP; |
| } |
| CONT; |
| JMP_JGE_X: |
| if (DST >= SRC) { |
| insn += insn->off; |
| CONT_JMP; |
| } |
| CONT; |
| JMP_JGE_K: |
| if (DST >= IMM) { |
| insn += insn->off; |
| CONT_JMP; |
| } |
| CONT; |
| JMP_JSGT_X: |
| if (((s64) DST) > ((s64) SRC)) { |
| insn += insn->off; |
| CONT_JMP; |
| } |
| CONT; |
| JMP_JSGT_K: |
| if (((s64) DST) > ((s64) IMM)) { |
| insn += insn->off; |
| CONT_JMP; |
| } |
| CONT; |
| JMP_JSGE_X: |
| if (((s64) DST) >= ((s64) SRC)) { |
| insn += insn->off; |
| CONT_JMP; |
| } |
| CONT; |
| JMP_JSGE_K: |
| if (((s64) DST) >= ((s64) IMM)) { |
| insn += insn->off; |
| CONT_JMP; |
| } |
| CONT; |
| JMP_JSET_X: |
| if (DST & SRC) { |
| insn += insn->off; |
| CONT_JMP; |
| } |
| CONT; |
| JMP_JSET_K: |
| if (DST & IMM) { |
| insn += insn->off; |
| CONT_JMP; |
| } |
| CONT; |
| JMP_EXIT: |
| return BPF_R0; |
| |
| /* STX and ST and LDX*/ |
| #define LDST(SIZEOP, SIZE) \ |
| STX_MEM_##SIZEOP: \ |
| *(SIZE *)(unsigned long) (DST + insn->off) = SRC; \ |
| CONT; \ |
| ST_MEM_##SIZEOP: \ |
| *(SIZE *)(unsigned long) (DST + insn->off) = IMM; \ |
| CONT; \ |
| LDX_MEM_##SIZEOP: \ |
| DST = *(SIZE *)(unsigned long) (SRC + insn->off); \ |
| CONT; |
| |
| LDST(B, u8) |
| LDST(H, u16) |
| LDST(W, u32) |
| LDST(DW, u64) |
| #undef LDST |
| STX_XADD_W: /* lock xadd *(u32 *)(dst_reg + off16) += src_reg */ |
| atomic_add((u32) SRC, (atomic_t *)(unsigned long) |
| (DST + insn->off)); |
| CONT; |
| STX_XADD_DW: /* lock xadd *(u64 *)(dst_reg + off16) += src_reg */ |
| atomic64_add((u64) SRC, (atomic64_t *)(unsigned long) |
| (DST + insn->off)); |
| CONT; |
| LD_ABS_W: /* BPF_R0 = ntohl(*(u32 *) (skb->data + imm32)) */ |
| off = IMM; |
| load_word: |
| /* BPF_LD + BPD_ABS and BPF_LD + BPF_IND insns are |
| * only appearing in the programs where ctx == |
| * skb. All programs keep 'ctx' in regs[BPF_REG_CTX] |
| * == BPF_R6, bpf_convert_filter() saves it in BPF_R6, |
| * internal BPF verifier will check that BPF_R6 == |
| * ctx. |
| * |
| * BPF_ABS and BPF_IND are wrappers of function calls, |
| * so they scratch BPF_R1-BPF_R5 registers, preserve |
| * BPF_R6-BPF_R9, and store return value into BPF_R0. |
| * |
| * Implicit input: |
| * ctx == skb == BPF_R6 == CTX |
| * |
| * Explicit input: |
| * SRC == any register |
| * IMM == 32-bit immediate |
| * |
| * Output: |
| * BPF_R0 - 8/16/32-bit skb data converted to cpu endianness |
| */ |
| |
| ptr = bpf_load_pointer((struct sk_buff *) (unsigned long) CTX, off, 4, &tmp); |
| if (likely(ptr != NULL)) { |
| BPF_R0 = get_unaligned_be32(ptr); |
| CONT; |
| } |
| |
| return 0; |
| LD_ABS_H: /* BPF_R0 = ntohs(*(u16 *) (skb->data + imm32)) */ |
| off = IMM; |
| load_half: |
| ptr = bpf_load_pointer((struct sk_buff *) (unsigned long) CTX, off, 2, &tmp); |
| if (likely(ptr != NULL)) { |
| BPF_R0 = get_unaligned_be16(ptr); |
| CONT; |
| } |
| |
| return 0; |
| LD_ABS_B: /* BPF_R0 = *(u8 *) (skb->data + imm32) */ |
| off = IMM; |
| load_byte: |
| ptr = bpf_load_pointer((struct sk_buff *) (unsigned long) CTX, off, 1, &tmp); |
| if (likely(ptr != NULL)) { |
| BPF_R0 = *(u8 *)ptr; |
| CONT; |
| } |
| |
| return 0; |
| LD_IND_W: /* BPF_R0 = ntohl(*(u32 *) (skb->data + src_reg + imm32)) */ |
| off = IMM + SRC; |
| goto load_word; |
| LD_IND_H: /* BPF_R0 = ntohs(*(u16 *) (skb->data + src_reg + imm32)) */ |
| off = IMM + SRC; |
| goto load_half; |
| LD_IND_B: /* BPF_R0 = *(u8 *) (skb->data + src_reg + imm32) */ |
| off = IMM + SRC; |
| goto load_byte; |
| |
| default_label: |
| /* If we ever reach this, we have a bug somewhere. */ |
| WARN_RATELIMIT(1, "unknown opcode %02x\n", insn->code); |
| return 0; |
| } |
| |
| void __weak bpf_int_jit_compile(struct bpf_prog *prog) |
| { |
| } |
| |
| /** |
| * bpf_prog_select_runtime - select execution runtime for BPF program |
| * @fp: bpf_prog populated with internal BPF program |
| * |
| * try to JIT internal BPF program, if JIT is not available select interpreter |
| * BPF program will be executed via BPF_PROG_RUN() macro |
| */ |
| void bpf_prog_select_runtime(struct bpf_prog *fp) |
| { |
| fp->bpf_func = (void *) __bpf_prog_run; |
| |
| /* Probe if internal BPF can be JITed */ |
| bpf_int_jit_compile(fp); |
| /* Lock whole bpf_prog as read-only */ |
| bpf_prog_lock_ro(fp); |
| } |
| EXPORT_SYMBOL_GPL(bpf_prog_select_runtime); |
| |
| static void bpf_prog_free_deferred(struct work_struct *work) |
| { |
| struct bpf_work_struct *ws; |
| |
| ws = container_of(work, struct bpf_work_struct, work); |
| bpf_jit_free(ws->prog); |
| } |
| |
| /* Free internal BPF program */ |
| void bpf_prog_free(struct bpf_prog *fp) |
| { |
| struct bpf_work_struct *ws = fp->work; |
| |
| INIT_WORK(&ws->work, bpf_prog_free_deferred); |
| ws->prog = fp; |
| schedule_work(&ws->work); |
| } |
| EXPORT_SYMBOL_GPL(bpf_prog_free); |