diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 3dcf591acd50..bf8cadd19593 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -5013,27 +5013,30 @@ static bool __is_pointer_value(bool allow_ptr_leaks, return reg->type != SCALAR_VALUE; } +static void clear_scalar_id(struct bpf_reg_state *reg) +{ + reg->id = 0; + reg->off = 0; +} + static void assign_scalar_id_before_mov(struct bpf_verifier_env *env, struct bpf_reg_state *src_reg) { if (src_reg->type != SCALAR_VALUE) return; - - if (src_reg->id & BPF_ADD_CONST) { - /* - * The verifier is processing rX = rY insn and - * rY->id has special linked register already. - * Cleared it, since multiple rX += const are not supported. - */ - src_reg->id = 0; - src_reg->off = 0; - } - + /* + * The verifier is processing rX = rY insn and + * rY->id has special linked register already. + * Cleared it, since multiple rX += const are not supported. + */ + if (src_reg->id & BPF_ADD_CONST) + clear_scalar_id(src_reg); + /* + * Ensure that src_reg has a valid ID that will be copied to + * dst_reg and then will be used by sync_linked_regs() to + * propagate min/max range. + */ if (!src_reg->id && !tnum_is_const(src_reg->var_off)) - /* Ensure that src_reg has a valid ID that will be copied to - * dst_reg and then will be used by sync_linked_regs() to - * propagate min/max range. - */ src_reg->id = ++env->id_gen; } @@ -5466,7 +5469,7 @@ static int check_stack_read_fixed_off(struct bpf_verifier_env *env, * coerce_reg_to_size will adjust the boundaries. */ if (get_reg_width(reg) > size * BITS_PER_BYTE) - state->regs[dst_regno].id = 0; + clear_scalar_id(&state->regs[dst_regno]); } else { int spill_cnt = 0, zero_cnt = 0; @@ -15476,7 +15479,7 @@ static void scalar_byte_swap(struct bpf_reg_state *dst_reg, struct bpf_insn *ins * any existing ties and avoid incorrect bounds propagation. */ if (need_bswap || insn->imm == 16 || insn->imm == 32) - dst_reg->id = 0; + clear_scalar_id(dst_reg); if (need_bswap) { if (insn->imm == 16) @@ -15845,8 +15848,7 @@ static int adjust_reg_min_max_vals(struct bpf_verifier_env *env, * we cannot accumulate another val into rx->off. */ clear_id: - dst_reg->off = 0; - dst_reg->id = 0; + clear_scalar_id(dst_reg); } else { if (alu32) dst_reg->id |= BPF_ADD_CONST32; @@ -15859,7 +15861,7 @@ clear_id: * Make sure ID is cleared otherwise dst_reg min/max could be * incorrectly propagated into other registers by sync_linked_regs() */ - dst_reg->id = 0; + clear_scalar_id(dst_reg); } return 0; } @@ -15990,7 +15992,7 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn) assign_scalar_id_before_mov(env, src_reg); copy_register_state(dst_reg, src_reg); if (!no_sext) - dst_reg->id = 0; + clear_scalar_id(dst_reg); coerce_reg_to_size_sx(dst_reg, insn->off >> 3); dst_reg->subreg_def = DEF_NOT_SUBREG; } else { @@ -16016,7 +16018,7 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn) * propagated into src_reg by sync_linked_regs() */ if (!is_src_reg_u32) - dst_reg->id = 0; + clear_scalar_id(dst_reg); dst_reg->subreg_def = env->insn_idx + 1; } else { /* case: W1 = (s8, s16)W2 */ @@ -16026,7 +16028,7 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn) assign_scalar_id_before_mov(env, src_reg); copy_register_state(dst_reg, src_reg); if (!no_sext) - dst_reg->id = 0; + clear_scalar_id(dst_reg); dst_reg->subreg_def = env->insn_idx + 1; coerce_subreg_to_size_sx(dst_reg, insn->off >> 3); } @@ -16856,7 +16858,7 @@ static void __collect_linked_regs(struct linked_regs *reg_set, struct bpf_reg_st e->is_reg = is_reg; e->regno = spi_or_reg; } else { - reg->id = 0; + clear_scalar_id(reg); } }