From: Yonghong Song yhs@fb.com
[ Upstream commit eb04bbb608e683f8fd3ef7f716e2fa32dd90861f ]
This patch added name checking for the following types: . BTF_KIND_PTR, BTF_KIND_ARRAY, BTF_KIND_VOLATILE, BTF_KIND_CONST, BTF_KIND_RESTRICT: the name must be null . BTF_KIND_STRUCT, BTF_KIND_UNION: the struct/member name is either null or a valid identifier . BTF_KIND_ENUM: the enum type name is either null or a valid identifier; the enumerator name must be a valid identifier. . BTF_KIND_FWD: the name must be a valid identifier . BTF_KIND_TYPEDEF: the name must be a valid identifier
For those places a valid name is required, the name must be a valid C identifier. This can be relaxed later if we found use cases for a different (non-C) frontend.
Fixes: 69b693f0aefa ("bpf: btf: Introduce BPF Type Format (BTF)") Acked-by: Martin KaFai Lau kafai@fb.com Signed-off-by: Yonghong Song yhs@fb.com Signed-off-by: Alexei Starovoitov ast@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/bpf/btf.c | 57 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+)
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index f0f9109f59bac..3e2413345e718 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -1168,6 +1168,22 @@ static int btf_ref_type_check_meta(struct btf_verifier_env *env, return -EINVAL; }
+ /* typedef type must have a valid name, and other ref types, + * volatile, const, restrict, should have a null name. + */ + if (BTF_INFO_KIND(t->info) == BTF_KIND_TYPEDEF) { + if (!t->name_off || + !btf_name_valid_identifier(env->btf, t->name_off)) { + btf_verifier_log_type(env, t, "Invalid name"); + return -EINVAL; + } + } else { + if (t->name_off) { + btf_verifier_log_type(env, t, "Invalid name"); + return -EINVAL; + } + } + btf_verifier_log_type(env, t, NULL);
return 0; @@ -1325,6 +1341,13 @@ static s32 btf_fwd_check_meta(struct btf_verifier_env *env, return -EINVAL; }
+ /* fwd type must have a valid name */ + if (!t->name_off || + !btf_name_valid_identifier(env->btf, t->name_off)) { + btf_verifier_log_type(env, t, "Invalid name"); + return -EINVAL; + } + btf_verifier_log_type(env, t, NULL);
return 0; @@ -1381,6 +1404,12 @@ static s32 btf_array_check_meta(struct btf_verifier_env *env, return -EINVAL; }
+ /* array type should not have a name */ + if (t->name_off) { + btf_verifier_log_type(env, t, "Invalid name"); + return -EINVAL; + } + if (btf_type_vlen(t)) { btf_verifier_log_type(env, t, "vlen != 0"); return -EINVAL; @@ -1557,6 +1586,13 @@ static s32 btf_struct_check_meta(struct btf_verifier_env *env, return -EINVAL; }
+ /* struct type either no name or a valid one */ + if (t->name_off && + !btf_name_valid_identifier(env->btf, t->name_off)) { + btf_verifier_log_type(env, t, "Invalid name"); + return -EINVAL; + } + btf_verifier_log_type(env, t, NULL);
last_offset = 0; @@ -1568,6 +1604,12 @@ static s32 btf_struct_check_meta(struct btf_verifier_env *env, return -EINVAL; }
+ /* struct member either no name or a valid one */ + if (member->name_off && + !btf_name_valid_identifier(btf, member->name_off)) { + btf_verifier_log_member(env, t, member, "Invalid name"); + return -EINVAL; + } /* A member cannot be in type void */ if (!member->type || !BTF_TYPE_ID_VALID(member->type)) { btf_verifier_log_member(env, t, member, @@ -1755,6 +1797,13 @@ static s32 btf_enum_check_meta(struct btf_verifier_env *env, return -EINVAL; }
+ /* enum type either no name or a valid one */ + if (t->name_off && + !btf_name_valid_identifier(env->btf, t->name_off)) { + btf_verifier_log_type(env, t, "Invalid name"); + return -EINVAL; + } + btf_verifier_log_type(env, t, NULL);
for (i = 0; i < nr_enums; i++) { @@ -1764,6 +1813,14 @@ static s32 btf_enum_check_meta(struct btf_verifier_env *env, return -EINVAL; }
+ /* enum member must have a valid name */ + if (!enums[i].name_off || + !btf_name_valid_identifier(btf, enums[i].name_off)) { + btf_verifier_log_type(env, t, "Invalid name"); + return -EINVAL; + } + + btf_verifier_log(env, "\t%s val=%d\n", btf_name_by_offset(btf, enums[i].name_off), enums[i].val);