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Diffstat (limited to 'kernel/bpf')
-rw-r--r--kernel/bpf/verifier.c238
1 files changed, 203 insertions, 35 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index e6d2a599c7d1..abfd57dd01e5 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -8521,6 +8521,9 @@ struct bpf_kfunc_call_arg_meta {
struct {
struct btf_field *field;
} arg_list_head;
+ struct {
+ struct btf_field *field;
+ } arg_rbtree_root;
};
static bool is_kfunc_acquire(struct bpf_kfunc_call_arg_meta *meta)
@@ -8632,6 +8635,8 @@ enum {
KF_ARG_DYNPTR_ID,
KF_ARG_LIST_HEAD_ID,
KF_ARG_LIST_NODE_ID,
+ KF_ARG_RB_ROOT_ID,
+ KF_ARG_RB_NODE_ID,
};
BTF_ID_LIST(kf_arg_btf_ids)
@@ -8673,6 +8678,16 @@ static bool is_kfunc_arg_list_node(const struct btf *btf, const struct btf_param
return __is_kfunc_ptr_arg_type(btf, arg, KF_ARG_LIST_NODE_ID);
}
+static bool is_kfunc_arg_rbtree_root(const struct btf *btf, const struct btf_param *arg)
+{
+ return __is_kfunc_ptr_arg_type(btf, arg, KF_ARG_RB_ROOT_ID);
+}
+
+static bool is_kfunc_arg_rbtree_node(const struct btf *btf, const struct btf_param *arg)
+{
+ return __is_kfunc_ptr_arg_type(btf, arg, KF_ARG_RB_NODE_ID);
+}
+
/* Returns true if struct is composed of scalars, 4 levels of nesting allowed */
static bool __btf_type_is_scalar_struct(struct bpf_verifier_env *env,
const struct btf *btf,
@@ -8732,6 +8747,8 @@ enum kfunc_ptr_arg_type {
KF_ARG_PTR_TO_BTF_ID, /* Also covers reg2btf_ids conversions */
KF_ARG_PTR_TO_MEM,
KF_ARG_PTR_TO_MEM_SIZE, /* Size derived from next argument, skip it */
+ KF_ARG_PTR_TO_RB_ROOT,
+ KF_ARG_PTR_TO_RB_NODE,
};
enum special_kfunc_type {
@@ -8839,6 +8856,12 @@ get_kfunc_ptr_arg_type(struct bpf_verifier_env *env,
if (is_kfunc_arg_list_node(meta->btf, &args[argno]))
return KF_ARG_PTR_TO_LIST_NODE;
+ if (is_kfunc_arg_rbtree_root(meta->btf, &args[argno]))
+ return KF_ARG_PTR_TO_RB_ROOT;
+
+ if (is_kfunc_arg_rbtree_node(meta->btf, &args[argno]))
+ return KF_ARG_PTR_TO_RB_NODE;
+
if ((base_type(reg->type) == PTR_TO_BTF_ID || reg2btf_ids[base_type(reg->type)])) {
if (!btf_type_is_struct(ref_t)) {
verbose(env, "kernel function %s args#%d pointer type %s %s is not supported\n",
@@ -9095,95 +9118,193 @@ static bool is_bpf_list_api_kfunc(u32 btf_id)
btf_id == special_kfunc_list[KF_bpf_list_pop_back];
}
-static int process_kf_arg_ptr_to_list_head(struct bpf_verifier_env *env,
- struct bpf_reg_state *reg, u32 regno,
- struct bpf_kfunc_call_arg_meta *meta)
+static bool is_bpf_rbtree_api_kfunc(u32 btf_id)
+{
+ return btf_id == special_kfunc_list[KF_bpf_rbtree_add] ||
+ btf_id == special_kfunc_list[KF_bpf_rbtree_remove] ||
+ btf_id == special_kfunc_list[KF_bpf_rbtree_first];
+}
+
+static bool is_bpf_graph_api_kfunc(u32 btf_id)
+{
+ return is_bpf_list_api_kfunc(btf_id) || is_bpf_rbtree_api_kfunc(btf_id);
+}
+
+static bool check_kfunc_is_graph_root_api(struct bpf_verifier_env *env,
+ enum btf_field_type head_field_type,
+ u32 kfunc_btf_id)
{
+ bool ret;
+
+ switch (head_field_type) {
+ case BPF_LIST_HEAD:
+ ret = is_bpf_list_api_kfunc(kfunc_btf_id);
+ break;
+ case BPF_RB_ROOT:
+ ret = is_bpf_rbtree_api_kfunc(kfunc_btf_id);
+ break;
+ default:
+ verbose(env, "verifier internal error: unexpected graph root argument type %s\n",
+ btf_field_type_name(head_field_type));
+ return false;
+ }
+
+ if (!ret)
+ verbose(env, "verifier internal error: %s head arg for unknown kfunc\n",
+ btf_field_type_name(head_field_type));
+ return ret;
+}
+
+static bool check_kfunc_is_graph_node_api(struct bpf_verifier_env *env,
+ enum btf_field_type node_field_type,
+ u32 kfunc_btf_id)
+{
+ bool ret;
+
+ switch (node_field_type) {
+ case BPF_LIST_NODE:
+ ret = (kfunc_btf_id == special_kfunc_list[KF_bpf_list_push_front] ||
+ kfunc_btf_id == special_kfunc_list[KF_bpf_list_push_back]);
+ break;
+ case BPF_RB_NODE:
+ ret = (kfunc_btf_id == special_kfunc_list[KF_bpf_rbtree_remove] ||
+ kfunc_btf_id == special_kfunc_list[KF_bpf_rbtree_add]);
+ break;
+ default:
+ verbose(env, "verifier internal error: unexpected graph node argument type %s\n",
+ btf_field_type_name(node_field_type));
+ return false;
+ }
+
+ if (!ret)
+ verbose(env, "verifier internal error: %s node arg for unknown kfunc\n",
+ btf_field_type_name(node_field_type));
+ return ret;
+}
+
+static int
+__process_kf_arg_ptr_to_graph_root(struct bpf_verifier_env *env,
+ struct bpf_reg_state *reg, u32 regno,
+ struct bpf_kfunc_call_arg_meta *meta,
+ enum btf_field_type head_field_type,
+ struct btf_field **head_field)
+{
+ const char *head_type_name;
struct btf_field *field;
struct btf_record *rec;
- u32 list_head_off;
+ u32 head_off;
- if (meta->btf != btf_vmlinux || !is_bpf_list_api_kfunc(meta->func_id)) {
- verbose(env, "verifier internal error: bpf_list_head argument for unknown kfunc\n");
+ if (meta->btf != btf_vmlinux) {
+ verbose(env, "verifier internal error: unexpected btf mismatch in kfunc call\n");
return -EFAULT;
}
+ if (!check_kfunc_is_graph_root_api(env, head_field_type, meta->func_id))
+ return -EFAULT;
+
+ head_type_name = btf_field_type_name(head_field_type);
if (!tnum_is_const(reg->var_off)) {
verbose(env,
- "R%d doesn't have constant offset. bpf_list_head has to be at the constant offset\n",
- regno);
+ "R%d doesn't have constant offset. %s has to be at the constant offset\n",
+ regno, head_type_name);
return -EINVAL;
}
rec = reg_btf_record(reg);
- list_head_off = reg->off + reg->var_off.value;
- field = btf_record_find(rec, list_head_off, BPF_LIST_HEAD);
+ head_off = reg->off + reg->var_off.value;
+ field = btf_record_find(rec, head_off, head_field_type);
if (!field) {
- verbose(env, "bpf_list_head not found at offset=%u\n", list_head_off);
+ verbose(env, "%s not found at offset=%u\n", head_type_name, head_off);
return -EINVAL;
}
/* All functions require bpf_list_head to be protected using a bpf_spin_lock */
if (check_reg_allocation_locked(env, reg)) {
- verbose(env, "bpf_spin_lock at off=%d must be held for bpf_list_head\n",
- rec->spin_lock_off);
+ verbose(env, "bpf_spin_lock at off=%d must be held for %s\n",
+ rec->spin_lock_off, head_type_name);
return -EINVAL;
}
- if (meta->arg_list_head.field) {
- verbose(env, "verifier internal error: repeating bpf_list_head arg\n");
+ if (*head_field) {
+ verbose(env, "verifier internal error: repeating %s arg\n", head_type_name);
return -EFAULT;
}
- meta->arg_list_head.field = field;
+ *head_field = field;
return 0;
}
-static int process_kf_arg_ptr_to_list_node(struct bpf_verifier_env *env,
+static int process_kf_arg_ptr_to_list_head(struct bpf_verifier_env *env,
struct bpf_reg_state *reg, u32 regno,
struct bpf_kfunc_call_arg_meta *meta)
{
+ return __process_kf_arg_ptr_to_graph_root(env, reg, regno, meta, BPF_LIST_HEAD,
+ &meta->arg_list_head.field);
+}
+
+static int process_kf_arg_ptr_to_rbtree_root(struct bpf_verifier_env *env,
+ struct bpf_reg_state *reg, u32 regno,
+ struct bpf_kfunc_call_arg_meta *meta)
+{
+ return __process_kf_arg_ptr_to_graph_root(env, reg, regno, meta, BPF_RB_ROOT,
+ &meta->arg_rbtree_root.field);
+}
+
+static int
+__process_kf_arg_ptr_to_graph_node(struct bpf_verifier_env *env,
+ struct bpf_reg_state *reg, u32 regno,
+ struct bpf_kfunc_call_arg_meta *meta,
+ enum btf_field_type head_field_type,
+ enum btf_field_type node_field_type,
+ struct btf_field **node_field)
+{
+ const char *node_type_name;
const struct btf_type *et, *t;
struct btf_field *field;
- u32 list_node_off;
+ u32 node_off;
- if (meta->btf != btf_vmlinux ||
- (meta->func_id != special_kfunc_list[KF_bpf_list_push_front] &&
- meta->func_id != special_kfunc_list[KF_bpf_list_push_back])) {
- verbose(env, "verifier internal error: bpf_list_node argument for unknown kfunc\n");
+ if (meta->btf != btf_vmlinux) {
+ verbose(env, "verifier internal error: unexpected btf mismatch in kfunc call\n");
return -EFAULT;
}
+ if (!check_kfunc_is_graph_node_api(env, node_field_type, meta->func_id))
+ return -EFAULT;
+
+ node_type_name = btf_field_type_name(node_field_type);
if (!tnum_is_const(reg->var_off)) {
verbose(env,
- "R%d doesn't have constant offset. bpf_list_node has to be at the constant offset\n",
- regno);
+ "R%d doesn't have constant offset. %s has to be at the constant offset\n",
+ regno, node_type_name);
return -EINVAL;
}
- list_node_off = reg->off + reg->var_off.value;
- field = reg_find_field_offset(reg, list_node_off, BPF_LIST_NODE);
- if (!field || field->offset != list_node_off) {
- verbose(env, "bpf_list_node not found at offset=%u\n", list_node_off);
+ node_off = reg->off + reg->var_off.value;
+ field = reg_find_field_offset(reg, node_off, node_field_type);
+ if (!field || field->offset != node_off) {
+ verbose(env, "%s not found at offset=%u\n", node_type_name, node_off);
return -EINVAL;
}
- field = meta->arg_list_head.field;
+ field = *node_field;
et = btf_type_by_id(field->graph_root.btf, field->graph_root.value_btf_id);
t = btf_type_by_id(reg->btf, reg->btf_id);
if (!btf_struct_ids_match(&env->log, reg->btf, reg->btf_id, 0, field->graph_root.btf,
field->graph_root.value_btf_id, true)) {
- verbose(env, "operation on bpf_list_head expects arg#1 bpf_list_node at offset=%d "
+ verbose(env, "operation on %s expects arg#1 %s at offset=%d "
"in struct %s, but arg is at offset=%d in struct %s\n",
+ btf_field_type_name(head_field_type),
+ btf_field_type_name(node_field_type),
field->graph_root.node_offset,
btf_name_by_offset(field->graph_root.btf, et->name_off),
- list_node_off, btf_name_by_offset(reg->btf, t->name_off));
+ node_off, btf_name_by_offset(reg->btf, t->name_off));
return -EINVAL;
}
- if (list_node_off != field->graph_root.node_offset) {
- verbose(env, "arg#1 offset=%d, but expected bpf_list_node at offset=%d in struct %s\n",
- list_node_off, field->graph_root.node_offset,
+ if (node_off != field->graph_root.node_offset) {
+ verbose(env, "arg#1 offset=%d, but expected %s at offset=%d in struct %s\n",
+ node_off, btf_field_type_name(node_field_type),
+ field->graph_root.node_offset,
btf_name_by_offset(field->graph_root.btf, et->name_off));
return -EINVAL;
}
@@ -9191,6 +9312,24 @@ static int process_kf_arg_ptr_to_list_node(struct bpf_verifier_env *env,
return 0;
}
+static int process_kf_arg_ptr_to_list_node(struct bpf_verifier_env *env,
+ struct bpf_reg_state *reg, u32 regno,
+ struct bpf_kfunc_call_arg_meta *meta)
+{
+ return __process_kf_arg_ptr_to_graph_node(env, reg, regno, meta,
+ BPF_LIST_HEAD, BPF_LIST_NODE,
+ &meta->arg_list_head.field);
+}
+
+static int process_kf_arg_ptr_to_rbtree_node(struct bpf_verifier_env *env,
+ struct bpf_reg_state *reg, u32 regno,
+ struct bpf_kfunc_call_arg_meta *meta)
+{
+ return __process_kf_arg_ptr_to_graph_node(env, reg, regno, meta,
+ BPF_RB_ROOT, BPF_RB_NODE,
+ &meta->arg_rbtree_root.field);
+}
+
static int check_kfunc_args(struct bpf_verifier_env *env, struct bpf_kfunc_call_arg_meta *meta)
{
const char *func_name = meta->func_name, *ref_tname;
@@ -9325,6 +9464,8 @@ static int check_kfunc_args(struct bpf_verifier_env *env, struct bpf_kfunc_call_
case KF_ARG_PTR_TO_DYNPTR:
case KF_ARG_PTR_TO_LIST_HEAD:
case KF_ARG_PTR_TO_LIST_NODE:
+ case KF_ARG_PTR_TO_RB_ROOT:
+ case KF_ARG_PTR_TO_RB_NODE:
case KF_ARG_PTR_TO_MEM:
case KF_ARG_PTR_TO_MEM_SIZE:
/* Trusted by default */
@@ -9403,6 +9544,20 @@ static int check_kfunc_args(struct bpf_verifier_env *env, struct bpf_kfunc_call_
if (ret < 0)
return ret;
break;
+ case KF_ARG_PTR_TO_RB_ROOT:
+ if (reg->type != PTR_TO_MAP_VALUE &&
+ reg->type != (PTR_TO_BTF_ID | MEM_ALLOC)) {
+ verbose(env, "arg#%d expected pointer to map value or allocated object\n", i);
+ return -EINVAL;
+ }
+ if (reg->type == (PTR_TO_BTF_ID | MEM_ALLOC) && !reg->ref_obj_id) {
+ verbose(env, "allocated object must be referenced\n");
+ return -EINVAL;
+ }
+ ret = process_kf_arg_ptr_to_rbtree_root(env, reg, regno, meta);
+ if (ret < 0)
+ return ret;
+ break;
case KF_ARG_PTR_TO_LIST_NODE:
if (reg->type != (PTR_TO_BTF_ID | MEM_ALLOC)) {
verbose(env, "arg#%d expected pointer to allocated object\n", i);
@@ -9416,6 +9571,19 @@ static int check_kfunc_args(struct bpf_verifier_env *env, struct bpf_kfunc_call_
if (ret < 0)
return ret;
break;
+ case KF_ARG_PTR_TO_RB_NODE:
+ if (reg->type != (PTR_TO_BTF_ID | MEM_ALLOC)) {
+ verbose(env, "arg#%d expected pointer to allocated object\n", i);
+ return -EINVAL;
+ }
+ if (!reg->ref_obj_id) {
+ verbose(env, "allocated object must be referenced\n");
+ return -EINVAL;
+ }
+ ret = process_kf_arg_ptr_to_rbtree_node(env, reg, regno, meta);
+ if (ret < 0)
+ return ret;
+ break;
case KF_ARG_PTR_TO_BTF_ID:
/* Only base_type is checked, further checks are done here */
if ((base_type(reg->type) != PTR_TO_BTF_ID ||
@@ -14417,7 +14585,7 @@ static int do_check(struct bpf_verifier_env *env)
if ((insn->src_reg == BPF_REG_0 && insn->imm != BPF_FUNC_spin_unlock) ||
(insn->src_reg == BPF_PSEUDO_CALL) ||
(insn->src_reg == BPF_PSEUDO_KFUNC_CALL &&
- (insn->off != 0 || !is_bpf_list_api_kfunc(insn->imm)))) {
+ (insn->off != 0 || !is_bpf_graph_api_kfunc(insn->imm)))) {
verbose(env, "function calls are not allowed while holding a lock\n");
return -EINVAL;
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-09-25 01:36:41 +0000