diff options
Diffstat (limited to 'kernel/bpf/verifier.c')
-rw-r--r-- | kernel/bpf/verifier.c | 119 |
1 files changed, 93 insertions, 26 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 3f93a548a642..1971ca325fb4 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -1387,21 +1387,24 @@ static bool may_access_direct_pkt_data(struct bpf_verifier_env *env, enum bpf_access_type t) { switch (env->prog->type) { + /* Program types only with direct read access go here! */ case BPF_PROG_TYPE_LWT_IN: case BPF_PROG_TYPE_LWT_OUT: case BPF_PROG_TYPE_LWT_SEG6LOCAL: case BPF_PROG_TYPE_SK_REUSEPORT: - /* dst_input() and dst_output() can't write for now */ + case BPF_PROG_TYPE_FLOW_DISSECTOR: + case BPF_PROG_TYPE_CGROUP_SKB: if (t == BPF_WRITE) return false; /* fallthrough */ + + /* Program types with direct read + write access go here! */ case BPF_PROG_TYPE_SCHED_CLS: case BPF_PROG_TYPE_SCHED_ACT: case BPF_PROG_TYPE_XDP: case BPF_PROG_TYPE_LWT_XMIT: case BPF_PROG_TYPE_SK_SKB: case BPF_PROG_TYPE_SK_MSG: - case BPF_PROG_TYPE_FLOW_DISSECTOR: if (meta) return meta->pkt_access; @@ -1528,14 +1531,19 @@ static bool __is_pointer_value(bool allow_ptr_leaks, return reg->type != SCALAR_VALUE; } +static struct bpf_reg_state *reg_state(struct bpf_verifier_env *env, int regno) +{ + return cur_regs(env) + regno; +} + static bool is_pointer_value(struct bpf_verifier_env *env, int regno) { - return __is_pointer_value(env->allow_ptr_leaks, cur_regs(env) + regno); + return __is_pointer_value(env->allow_ptr_leaks, reg_state(env, regno)); } static bool is_ctx_reg(struct bpf_verifier_env *env, int regno) { - const struct bpf_reg_state *reg = cur_regs(env) + regno; + const struct bpf_reg_state *reg = reg_state(env, regno); return reg->type == PTR_TO_CTX || reg->type == PTR_TO_SOCKET; @@ -1543,11 +1551,19 @@ static bool is_ctx_reg(struct bpf_verifier_env *env, int regno) static bool is_pkt_reg(struct bpf_verifier_env *env, int regno) { - const struct bpf_reg_state *reg = cur_regs(env) + regno; + const struct bpf_reg_state *reg = reg_state(env, regno); return type_is_pkt_pointer(reg->type); } +static bool is_flow_key_reg(struct bpf_verifier_env *env, int regno) +{ + const struct bpf_reg_state *reg = reg_state(env, regno); + + /* Separate to is_ctx_reg() since we still want to allow BPF_ST here. */ + return reg->type == PTR_TO_FLOW_KEYS; +} + static int check_pkt_ptr_alignment(struct bpf_verifier_env *env, const struct bpf_reg_state *reg, int off, int size, bool strict) @@ -1956,9 +1972,11 @@ static int check_xadd(struct bpf_verifier_env *env, int insn_idx, struct bpf_ins } if (is_ctx_reg(env, insn->dst_reg) || - is_pkt_reg(env, insn->dst_reg)) { + is_pkt_reg(env, insn->dst_reg) || + is_flow_key_reg(env, insn->dst_reg)) { verbose(env, "BPF_XADD stores into R%d %s is not allowed\n", - insn->dst_reg, reg_type_str[insn->dst_reg]); + insn->dst_reg, + reg_type_str[reg_state(env, insn->dst_reg)->type]); return -EACCES; } @@ -1983,7 +2001,7 @@ static int check_stack_boundary(struct bpf_verifier_env *env, int regno, int access_size, bool zero_size_allowed, struct bpf_call_arg_meta *meta) { - struct bpf_reg_state *reg = cur_regs(env) + regno; + struct bpf_reg_state *reg = reg_state(env, regno); struct bpf_func_state *state = func(env, reg); int off, i, slot, spi; @@ -2062,8 +2080,6 @@ static int check_helper_mem_access(struct bpf_verifier_env *env, int regno, case PTR_TO_PACKET_META: return check_packet_access(env, regno, reg->off, access_size, zero_size_allowed); - case PTR_TO_FLOW_KEYS: - return check_flow_keys_access(env, reg->off, access_size); case PTR_TO_MAP_VALUE: return check_map_access(env, regno, reg->off, access_size, zero_size_allowed); @@ -2117,7 +2133,8 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 regno, } if (arg_type == ARG_PTR_TO_MAP_KEY || - arg_type == ARG_PTR_TO_MAP_VALUE) { + arg_type == ARG_PTR_TO_MAP_VALUE || + arg_type == ARG_PTR_TO_UNINIT_MAP_VALUE) { expected_type = PTR_TO_STACK; if (!type_is_pkt_pointer(type) && type != PTR_TO_MAP_VALUE && type != expected_type) @@ -2187,7 +2204,8 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 regno, err = check_helper_mem_access(env, regno, meta->map_ptr->key_size, false, NULL); - } else if (arg_type == ARG_PTR_TO_MAP_VALUE) { + } else if (arg_type == ARG_PTR_TO_MAP_VALUE || + arg_type == ARG_PTR_TO_UNINIT_MAP_VALUE) { /* bpf_map_xxx(..., map_ptr, ..., value) call: * check [value, value + map->value_size) validity */ @@ -2196,9 +2214,10 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 regno, verbose(env, "invalid map_ptr to access map->value\n"); return -EACCES; } + meta->raw_mode = (arg_type == ARG_PTR_TO_UNINIT_MAP_VALUE); err = check_helper_mem_access(env, regno, meta->map_ptr->value_size, false, - NULL); + meta); } else if (arg_type_is_mem_size(arg_type)) { bool zero_size_allowed = (arg_type == ARG_CONST_SIZE_OR_ZERO); @@ -2321,6 +2340,13 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env, if (func_id != BPF_FUNC_sk_select_reuseport) goto error; break; + case BPF_MAP_TYPE_QUEUE: + case BPF_MAP_TYPE_STACK: + if (func_id != BPF_FUNC_map_peek_elem && + func_id != BPF_FUNC_map_pop_elem && + func_id != BPF_FUNC_map_push_elem) + goto error; + break; default: break; } @@ -2377,6 +2403,13 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env, if (map->map_type != BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) goto error; break; + case BPF_FUNC_map_peek_elem: + case BPF_FUNC_map_pop_elem: + case BPF_FUNC_map_push_elem: + if (map->map_type != BPF_MAP_TYPE_QUEUE && + map->map_type != BPF_MAP_TYPE_STACK) + goto error; + break; default: break; } @@ -2672,7 +2705,10 @@ record_func_map(struct bpf_verifier_env *env, struct bpf_call_arg_meta *meta, if (func_id != BPF_FUNC_tail_call && func_id != BPF_FUNC_map_lookup_elem && func_id != BPF_FUNC_map_update_elem && - func_id != BPF_FUNC_map_delete_elem) + func_id != BPF_FUNC_map_delete_elem && + func_id != BPF_FUNC_map_push_elem && + func_id != BPF_FUNC_map_pop_elem && + func_id != BPF_FUNC_map_peek_elem) return 0; if (meta->map_ptr == NULL) { @@ -2816,10 +2852,6 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn regs[BPF_REG_0].type = NOT_INIT; } else if (fn->ret_type == RET_PTR_TO_MAP_VALUE_OR_NULL || fn->ret_type == RET_PTR_TO_MAP_VALUE) { - if (fn->ret_type == RET_PTR_TO_MAP_VALUE) - regs[BPF_REG_0].type = PTR_TO_MAP_VALUE; - else - regs[BPF_REG_0].type = PTR_TO_MAP_VALUE_OR_NULL; /* There is no offset yet applied, variable or fixed */ mark_reg_known_zero(env, regs, BPF_REG_0); /* remember map_ptr, so that check_map_access() @@ -2832,7 +2864,12 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn return -EINVAL; } regs[BPF_REG_0].map_ptr = meta.map_ptr; - regs[BPF_REG_0].id = ++env->id_gen; + if (fn->ret_type == RET_PTR_TO_MAP_VALUE) { + regs[BPF_REG_0].type = PTR_TO_MAP_VALUE; + } else { + regs[BPF_REG_0].type = PTR_TO_MAP_VALUE_OR_NULL; + regs[BPF_REG_0].id = ++env->id_gen; + } } else if (fn->ret_type == RET_PTR_TO_SOCKET_OR_NULL) { int id = acquire_reference_state(env, insn_idx); if (id < 0) @@ -3010,7 +3047,7 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env, dst_reg->umax_value = umax_ptr; dst_reg->var_off = ptr_reg->var_off; dst_reg->off = ptr_reg->off + smin_val; - dst_reg->range = ptr_reg->range; + dst_reg->raw = ptr_reg->raw; break; } /* A new variable offset is created. Note that off_reg->off @@ -3040,10 +3077,11 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env, } dst_reg->var_off = tnum_add(ptr_reg->var_off, off_reg->var_off); dst_reg->off = ptr_reg->off; + dst_reg->raw = ptr_reg->raw; if (reg_is_pkt_pointer(ptr_reg)) { dst_reg->id = ++env->id_gen; /* something was added to pkt_ptr, set range to zero */ - dst_reg->range = 0; + dst_reg->raw = 0; } break; case BPF_SUB: @@ -3072,7 +3110,7 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env, dst_reg->var_off = ptr_reg->var_off; dst_reg->id = ptr_reg->id; dst_reg->off = ptr_reg->off - smin_val; - dst_reg->range = ptr_reg->range; + dst_reg->raw = ptr_reg->raw; break; } /* A new variable offset is created. If the subtrahend is known @@ -3098,11 +3136,12 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env, } dst_reg->var_off = tnum_sub(ptr_reg->var_off, off_reg->var_off); dst_reg->off = ptr_reg->off; + dst_reg->raw = ptr_reg->raw; if (reg_is_pkt_pointer(ptr_reg)) { dst_reg->id = ++env->id_gen; /* something was added to pkt_ptr, set range to zero */ if (smin_val < 0) - dst_reg->range = 0; + dst_reg->raw = 0; } break; case BPF_AND: @@ -5244,7 +5283,8 @@ static int do_check(struct bpf_verifier_env *env) if (is_ctx_reg(env, insn->dst_reg)) { verbose(env, "BPF_ST stores into R%d %s is not allowed\n", - insn->dst_reg, reg_type_str[insn->dst_reg]); + insn->dst_reg, + reg_type_str[reg_state(env, insn->dst_reg)->type]); return -EACCES; } @@ -5672,7 +5712,11 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env) bool is_narrower_load; u32 target_size; - if (ops->gen_prologue) { + if (ops->gen_prologue || env->seen_direct_write) { + if (!ops->gen_prologue) { + verbose(env, "bpf verifier is misconfigured\n"); + return -EINVAL; + } cnt = ops->gen_prologue(insn_buf, env->seen_direct_write, env->prog); if (cnt >= ARRAY_SIZE(insn_buf)) { @@ -6144,7 +6188,10 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env) if (prog->jit_requested && BITS_PER_LONG == 64 && (insn->imm == BPF_FUNC_map_lookup_elem || insn->imm == BPF_FUNC_map_update_elem || - insn->imm == BPF_FUNC_map_delete_elem)) { + insn->imm == BPF_FUNC_map_delete_elem || + insn->imm == BPF_FUNC_map_push_elem || + insn->imm == BPF_FUNC_map_pop_elem || + insn->imm == BPF_FUNC_map_peek_elem)) { aux = &env->insn_aux_data[i + delta]; if (bpf_map_ptr_poisoned(aux)) goto patch_call_imm; @@ -6177,6 +6224,14 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env) BUILD_BUG_ON(!__same_type(ops->map_update_elem, (int (*)(struct bpf_map *map, void *key, void *value, u64 flags))NULL)); + BUILD_BUG_ON(!__same_type(ops->map_push_elem, + (int (*)(struct bpf_map *map, void *value, + u64 flags))NULL)); + BUILD_BUG_ON(!__same_type(ops->map_pop_elem, + (int (*)(struct bpf_map *map, void *value))NULL)); + BUILD_BUG_ON(!__same_type(ops->map_peek_elem, + (int (*)(struct bpf_map *map, void *value))NULL)); + switch (insn->imm) { case BPF_FUNC_map_lookup_elem: insn->imm = BPF_CAST_CALL(ops->map_lookup_elem) - @@ -6190,6 +6245,18 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env) insn->imm = BPF_CAST_CALL(ops->map_delete_elem) - __bpf_call_base; continue; + case BPF_FUNC_map_push_elem: + insn->imm = BPF_CAST_CALL(ops->map_push_elem) - + __bpf_call_base; + continue; + case BPF_FUNC_map_pop_elem: + insn->imm = BPF_CAST_CALL(ops->map_pop_elem) - + __bpf_call_base; + continue; + case BPF_FUNC_map_peek_elem: + insn->imm = BPF_CAST_CALL(ops->map_peek_elem) - + __bpf_call_base; + continue; } goto patch_call_imm; |