diff options
Diffstat (limited to 'kernel/bpf/core.c')
| -rw-r--r-- | kernel/bpf/core.c | 96 |
1 files changed, 8 insertions, 88 deletions
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 90feeba3a1a1..1127552c8033 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -634,23 +634,6 @@ static int bpf_jit_blind_insn(const struct bpf_insn *from, *to++ = BPF_JMP_REG(from->code, from->dst_reg, BPF_REG_AX, off); break; - case BPF_LD | BPF_ABS | BPF_W: - case BPF_LD | BPF_ABS | BPF_H: - case BPF_LD | BPF_ABS | BPF_B: - *to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm); - *to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd); - *to++ = BPF_LD_IND(from->code, BPF_REG_AX, 0); - break; - - case BPF_LD | BPF_IND | BPF_W: - case BPF_LD | BPF_IND | BPF_H: - case BPF_LD | BPF_IND | BPF_B: - *to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm); - *to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd); - *to++ = BPF_ALU32_REG(BPF_ADD, BPF_REG_AX, from->src_reg); - *to++ = BPF_LD_IND(from->code, BPF_REG_AX, 0); - break; - case BPF_LD | BPF_IMM | BPF_DW: *to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ aux[1].imm); *to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd); @@ -891,14 +874,7 @@ EXPORT_SYMBOL_GPL(__bpf_call_base); INSN_3(LDX, MEM, W), \ INSN_3(LDX, MEM, DW), \ /* Immediate based. */ \ - INSN_3(LD, IMM, DW), \ - /* Misc (old cBPF carry-over). */ \ - INSN_3(LD, ABS, B), \ - INSN_3(LD, ABS, H), \ - INSN_3(LD, ABS, W), \ - INSN_3(LD, IND, B), \ - INSN_3(LD, IND, H), \ - INSN_3(LD, IND, W) + INSN_3(LD, IMM, DW) bool bpf_opcode_in_insntable(u8 code) { @@ -908,6 +884,13 @@ bool bpf_opcode_in_insntable(u8 code) [0 ... 255] = false, /* Now overwrite non-defaults ... */ BPF_INSN_MAP(BPF_INSN_2_TBL, BPF_INSN_3_TBL), + /* UAPI exposed, but rewritten opcodes. cBPF carry-over. */ + [BPF_LD | BPF_ABS | BPF_B] = true, + [BPF_LD | BPF_ABS | BPF_H] = true, + [BPF_LD | BPF_ABS | BPF_W] = true, + [BPF_LD | BPF_IND | BPF_B] = true, + [BPF_LD | BPF_IND | BPF_H] = true, + [BPF_LD | BPF_IND | BPF_W] = true, }; #undef BPF_INSN_3_TBL #undef BPF_INSN_2_TBL @@ -938,8 +921,6 @@ static u64 ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn, u64 *stack) #undef BPF_INSN_3_LBL #undef BPF_INSN_2_LBL u32 tail_call_cnt = 0; - void *ptr; - int off; #define CONT ({ insn++; goto select_insn; }) #define CONT_JMP ({ insn++; goto select_insn; }) @@ -1266,67 +1247,6 @@ out: 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 - * (see may_access_skb() in the verifier). 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. Die hard here |