diff options
Diffstat (limited to 'kernel/bpf/btf.c')
-rw-r--r-- | kernel/bpf/btf.c | 1055 |
1 files changed, 906 insertions, 149 deletions
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 378cef70341c..bd3921b1514b 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -5,6 +5,7 @@ #include <uapi/linux/types.h> #include <linux/seq_file.h> #include <linux/compiler.h> +#include <linux/ctype.h> #include <linux/errno.h> #include <linux/slab.h> #include <linux/anon_inodes.h> @@ -156,14 +157,14 @@ * */ -#define BITS_PER_U64 (sizeof(u64) * BITS_PER_BYTE) +#define BITS_PER_U128 (sizeof(u64) * BITS_PER_BYTE * 2) #define BITS_PER_BYTE_MASK (BITS_PER_BYTE - 1) #define BITS_PER_BYTE_MASKED(bits) ((bits) & BITS_PER_BYTE_MASK) #define BITS_ROUNDDOWN_BYTES(bits) ((bits) >> 3) #define BITS_ROUNDUP_BYTES(bits) \ (BITS_ROUNDDOWN_BYTES(bits) + !!BITS_PER_BYTE_MASKED(bits)) -#define BTF_INFO_MASK 0x0f00ffff +#define BTF_INFO_MASK 0x8f00ffff #define BTF_INT_MASK 0x0fffffff #define BTF_TYPE_ID_VALID(type_id) ((type_id) <= BTF_MAX_TYPE) #define BTF_STR_OFFSET_VALID(name_off) ((name_off) <= BTF_MAX_NAME_OFFSET) @@ -259,6 +260,8 @@ static const char * const btf_kind_str[NR_BTF_KINDS] = { [BTF_KIND_VOLATILE] = "VOLATILE", [BTF_KIND_CONST] = "CONST", [BTF_KIND_RESTRICT] = "RESTRICT", + [BTF_KIND_FUNC] = "FUNC", + [BTF_KIND_FUNC_PROTO] = "FUNC_PROTO", }; struct btf_kind_operations { @@ -271,6 +274,10 @@ struct btf_kind_operations { const struct btf_type *struct_type, const struct btf_member *member, const struct btf_type *member_type); + int (*check_kflag_member)(struct btf_verifier_env *env, + const struct btf_type *struct_type, + const struct btf_member *member, + const struct btf_type *member_type); void (*log_details)(struct btf_verifier_env *env, const struct btf_type *t); void (*seq_show)(const struct btf *btf, const struct btf_type *t, @@ -281,6 +288,9 @@ struct btf_kind_operations { static const struct btf_kind_operations * const kind_ops[NR_BTF_KINDS]; static struct btf_type btf_void; +static int btf_resolve(struct btf_verifier_env *env, + const struct btf_type *t, u32 type_id); + static bool btf_type_is_modifier(const struct btf_type *t) { /* Some of them is not strictly a C modifier @@ -306,15 +316,33 @@ static bool btf_type_is_modifier(const struct btf_type *t) static bool btf_type_is_void(const struct btf_type *t) { - /* void => no type and size info. - * Hence, FWD is also treated as void. - */ - return t == &btf_void || BTF_INFO_KIND(t->info) == BTF_KIND_FWD; + return t == &btf_void; +} + +static bool btf_type_is_fwd(const struct btf_type *t) +{ + return BTF_INFO_KIND(t->info) == BTF_KIND_FWD; +} + +static bool btf_type_is_func(const struct btf_type *t) +{ + return BTF_INFO_KIND(t->info) == BTF_KIND_FUNC; +} + +static bool btf_type_is_func_proto(const struct btf_type *t) +{ + return BTF_INFO_KIND(t->info) == BTF_KIND_FUNC_PROTO; +} + +static bool btf_type_nosize(const struct btf_type *t) +{ + return btf_type_is_void(t) || btf_type_is_fwd(t) || + btf_type_is_func(t) || btf_type_is_func_proto(t); } -static bool btf_type_is_void_or_null(const struct btf_type *t) +static bool btf_type_nosize_or_null(const struct btf_type *t) { - return !t || btf_type_is_void(t); + return !t || btf_type_nosize(t); } /* union is only a special case of struct: @@ -327,6 +355,11 @@ static bool btf_type_is_struct(const struct btf_type *t) return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION; } +static bool __btf_type_is_struct(const struct btf_type *t) +{ + return BTF_INFO_KIND(t->info) == BTF_KIND_STRUCT; +} + static bool btf_type_is_array(const struct btf_type *t) { return BTF_INFO_KIND(t->info) == BTF_KIND_ARRAY; @@ -395,6 +428,25 @@ static u16 btf_type_vlen(const struct btf_type *t) return BTF_INFO_VLEN(t->info); } +static bool btf_type_kflag(const struct btf_type *t) +{ + return BTF_INFO_KFLAG(t->info); +} + +static u32 btf_member_bit_offset(const struct btf_type *struct_type, + const struct btf_member *member) +{ + return btf_type_kflag(struct_type) ? BTF_MEMBER_BIT_OFFSET(member->offset) + : member->offset; +} + +static u32 btf_member_bitfield_size(const struct btf_type *struct_type, + const struct btf_member *member) +{ + return btf_type_kflag(struct_type) ? BTF_MEMBER_BITFIELD_SIZE(member->offset) + : 0; +} + static u32 btf_type_int(const struct btf_type *t) { return *(u32 *)(t + 1); @@ -426,7 +478,31 @@ static bool btf_name_offset_valid(const struct btf *btf, u32 offset) offset < btf->hdr.str_len; } -static const char *btf_name_by_offset(const struct btf *btf, u32 offset) +/* Only C-style identifier is permitted. This can be relaxed if + * necessary. + */ +static bool btf_name_valid_identifier(const struct btf *btf, u32 offset) +{ + /* offset must be valid */ + const char *src = &btf->strings[offset]; + const char *src_limit; + + if (!isalpha(*src) && *src != '_') + return false; + + /* set a limit on identifier length */ + src_limit = src + KSYM_NAME_LEN; + src++; + while (*src && src < src_limit) { + if (!isalnum(*src) && *src != '_') + return false; + src++; + } + + return !*src; +} + +static const char *__btf_name_by_offset(const struct btf *btf, u32 offset) { if (!offset) return "(anon)"; @@ -436,7 +512,15 @@ static const char *btf_name_by_offset(const struct btf *btf, u32 offset) return "(invalid-name-offset)"; } -static const struct btf_type *btf_type_by_id(const struct btf *btf, u32 type_id) +const char *btf_name_by_offset(const struct btf *btf, u32 offset) +{ + if (offset < btf->hdr.str_len) + return &btf->strings[offset]; + + return NULL; +} + +const struct btf_type *btf_type_by_id(const struct btf *btf, u32 type_id) { if (type_id > btf->nr_types) return NULL; @@ -446,7 +530,7 @@ static const struct btf_type *btf_type_by_id(const struct btf *btf, u32 type_id) /* * Regular int is not a bit field and it must be either - * u8/u16/u32/u64. + * u8/u16/u32/u64 or __int128. */ static bool btf_type_int_is_regular(const struct btf_type *t) { @@ -459,13 +543,55 @@ static bool btf_type_int_is_regular(const struct btf_type *t) if (BITS_PER_BYTE_MASKED(nr_bits) || BTF_INT_OFFSET(int_data) || (nr_bytes != sizeof(u8) && nr_bytes != sizeof(u16) && - nr_bytes != sizeof(u32) && nr_bytes != sizeof(u64))) { + nr_bytes != sizeof(u32) && nr_bytes != sizeof(u64) && + nr_bytes != (2 * sizeof(u64)))) { return false; } return true; } +/* + * Check that given struct member is a regular int with expected + * offset and size. + */ +bool btf_member_is_reg_int(const struct btf *btf, const struct btf_type *s, + const struct btf_member *m, + u32 expected_offset, u32 expected_size) +{ + const struct btf_type *t; + u32 id, int_data; + u8 nr_bits; + + id = m->type; + t = btf_type_id_size(btf, &id, NULL); + if (!t || !btf_type_is_int(t)) + return false; + + int_data = btf_type_int(t); + nr_bits = BTF_INT_BITS(int_data); + if (btf_type_kflag(s)) { + u32 bitfield_size = BTF_MEMBER_BITFIELD_SIZE(m->offset); + u32 bit_offset = BTF_MEMBER_BIT_OFFSET(m->offset); + + /* if kflag set, int should be a regular int and + * bit offset should be at byte boundary. + */ + return !bitfield_size && + BITS_ROUNDUP_BYTES(bit_offset) == expected_offset && + BITS_ROUNDUP_BYTES(nr_bits) == expected_size; + } + + if (BTF_INT_OFFSET(int_data) || + BITS_PER_BYTE_MASKED(m->offset) || + BITS_ROUNDUP_BYTES(m->offset) != expected_offset || + BITS_PER_BYTE_MASKED(nr_bits) || + BITS_ROUNDUP_BYTES(nr_bits) != expected_size) + return false; + + return true; +} + __printf(2, 3) static void __btf_verifier_log(struct bpf_verifier_log *log, const char *fmt, ...) { @@ -506,7 +632,7 @@ __printf(4, 5) static void __btf_verifier_log_type(struct btf_verifier_env *env, __btf_verifier_log(log, "[%u] %s %s%s", env->log_type_id, btf_kind_str[kind], - btf_name_by_offset(btf, t->name_off), + __btf_name_by_offset(btf, t->name_off), log_details ? " " : ""); if (log_details) @@ -549,9 +675,17 @@ static void btf_verifier_log_member(struct btf_verifier_env *env, if (env->phase != CHECK_META) btf_verifier_log_type(env, struct_type, NULL); - __btf_verifier_log(log, "\t%s type_id=%u bits_offset=%u", - btf_name_by_offset(btf, member->name_off), - member->type, member->offset); + if (btf_type_kflag(struct_type)) + __btf_verifier_log(log, + "\t%s type_id=%u bitfield_size=%u bits_offset=%u", + __btf_name_by_offset(btf, member->name_off), + member->type, + BTF_MEMBER_BITFIELD_SIZE(member->offset), + BTF_MEMBER_BIT_OFFSET(member->offset)); + else + __btf_verifier_log(log, "\t%s type_id=%u bits_offset=%u", + __btf_name_by_offset(btf, member->name_off), + member->type, member->offset); if (fmt && *fmt) { __btf_verifier_log(log, " "); @@ -740,11 +874,15 @@ static bool env_type_is_resolve_sink(const struct btf_verifier_env *env, /* int, enum or void is a sink */ return !btf_type_needs_resolve(next_type); case RESOLVE_PTR: - /* int, enum, void, struct or array is a sink for ptr */ + /* int, enum, void, struct, array, func or func_proto is a sink + * for ptr + */ return !btf_type_is_modifier(next_type) && !btf_type_is_ptr(next_type); case RESOLVE_STRUCT_OR_ARRAY: - /* int, enum, void or ptr is a sink for struct and array */ + /* int, enum, void, ptr, func or func_proto is a sink + * for struct and array + */ return !btf_type_is_modifier(next_type) && !btf_type_is_array(next_type) && !btf_type_is_struct(next_type); @@ -826,7 +964,7 @@ const struct btf_type *btf_type_id_size(const struct btf *btf, u32 size = 0; size_type = btf_type_by_id(btf, size_type_id); - if (btf_type_is_void_or_null(size_type)) + if (btf_type_nosize_or_null(size_type)) return NULL; if (btf_type_has_size(size_type)) { @@ -842,7 +980,7 @@ const struct btf_type *btf_type_id_size(const struct btf *btf, size = btf->resolved_sizes[size_type_id]; size_type_id = btf->resolved_ids[size_type_id]; size_type = btf_type_by_id(btf, size_type_id); - if (btf_type_is_void(size_type)) + if (btf_type_nosize_or_null(size_type)) return NULL; } @@ -863,6 +1001,38 @@ static int btf_df_check_member(struct btf_verifier_env *env, return -EINVAL; } +static int btf_df_check_kflag_member(struct btf_verifier_env *env, + const struct btf_type *struct_type, + const struct btf_member *member, + const struct btf_type *member_type) +{ + btf_verifier_log_basic(env, struct_type, + "Unsupported check_kflag_member"); + return -EINVAL; +} + +/* Used for ptr, array and struct/union type members. + * int, enum and modifier types have their specific callback functions. + */ +static int btf_generic_check_kflag_member(struct btf_verifier_env *env, + const struct btf_type *struct_type, + const struct btf_member *member, + const struct btf_type *member_type) +{ + if (BTF_MEMBER_BITFIELD_SIZE(member->offset)) { + btf_verifier_log_member(env, struct_type, member, + "Invalid member bitfield_size"); + return -EINVAL; + } + + /* bitfield size is 0, so member->offset represents bit offset only. + * It is safe to call non kflag check_member variants. + */ + return btf_type_ops(member_type)->check_member(env, struct_type, + member, + member_type); +} + static int btf_df_resolve(struct btf_verifier_env *env, const struct resolve_vertex *v) { @@ -899,9 +1069,65 @@ static int btf_int_check_member(struct btf_verifier_env *env, nr_copy_bits = BTF_INT_BITS(int_data) + BITS_PER_BYTE_MASKED(struct_bits_off); - if (nr_copy_bits > BITS_PER_U64) { + if (nr_copy_bits > BITS_PER_U128) { btf_verifier_log_member(env, struct_type, member, - "nr_copy_bits exceeds 64"); + "nr_copy_bits exceeds 128"); + return -EINVAL; + } + + if (struct_size < bytes_offset || + struct_size - bytes_offset < BITS_ROUNDUP_BYTES(nr_copy_bits)) { + btf_verifier_log_member(env, struct_type, member, + "Member exceeds struct_size"); + return -EINVAL; + } + + return 0; +} + +static int btf_int_check_kflag_member(struct btf_verifier_env *env, + const struct btf_type *struct_type, + const struct btf_member *member, + const struct btf_type *member_type) +{ + u32 struct_bits_off, nr_bits, nr_int_data_bits, bytes_offset; + u32 int_data = btf_type_int(member_type); + u32 struct_size = struct_type->size; + u32 nr_copy_bits; + + /* a regular int type is required for the kflag int member */ + if (!btf_type_int_is_regular(member_type)) { + btf_verifier_log_member(env, struct_type, member, + "Invalid member base type"); + return -EINVAL; + } + + /* check sanity of bitfield size */ + nr_bits = BTF_MEMBER_BITFIELD_SIZE(member->offset); + struct_bits_off = BTF_MEMBER_BIT_OFFSET(member->offset); + nr_int_data_bits = BTF_INT_BITS(int_data); + if (!nr_bits) { + /* Not a bitfield member, member offset must be at byte + * boundary. + */ + if (BITS_PER_BYTE_MASKED(struct_bits_off)) { + btf_verifier_log_member(env, struct_type, member, + "Invalid member offset"); + return -EINVAL; + } + + nr_bits = nr_int_data_bits; + } else if (nr_bits > nr_int_data_bits) { + btf_verifier_log_member(env, struct_type, member, + "Invalid member bitfield_size"); + return -EINVAL; + } + + bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off); + nr_copy_bits = nr_bits + BITS_PER_BYTE_MASKED(struct_bits_off); + if (nr_copy_bits > BITS_PER_U128) { + btf_verifier_log_member(env, struct_type, member, + "nr_copy_bits exceeds 128"); return -EINVAL; } @@ -934,6 +1160,11 @@ static s32 btf_int_check_meta(struct btf_verifier_env *env, return -EINVAL; } + if (btf_type_kflag(t)) { + btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); + return -EINVAL; + } + int_data = btf_type_int(t); if (int_data & ~BTF_INT_MASK) { btf_verifier_log_basic(env, t, "Invalid int_data:%x", @@ -943,9 +1174,9 @@ static s32 btf_int_check_meta(struct btf_verifier_env *env, nr_bits = BTF_INT_BITS(int_data) + BTF_INT_OFFSET(int_data); - if (nr_bits > BITS_PER_U64) { + if (nr_bits > BITS_PER_U128) { btf_verifier_log_type(env, t, "nr_bits exceeds %zu", - BITS_PER_U64); + BITS_PER_U128); return -EINVAL; } @@ -986,43 +1217,113 @@ static void btf_int_log(struct btf_verifier_env *env, btf_int_encoding_str(BTF_INT_ENCODING(int_data))); } -static void btf_int_bits_seq_show(const struct btf *btf, - const struct btf_type *t, - void *data, u8 bits_offset, - struct seq_file *m) +static void btf_int128_print(struct seq_file *m, void *data) +{ + /* data points to a __int128 number. + * Suppose + * int128_num = *(__int128 *)data; + * The below formulas shows what upper_num and lower_num represents: + * upper_num = int128_num >> 64; + * lower_num = int128_num & 0xffffffffFFFFFFFFULL; + */ + u64 upper_num, lower_num; + +#ifdef __BIG_ENDIAN_BITFIELD + upper_num = *(u64 *)data; + lower_num = *(u64 *)(data + 8); +#else + upper_num = *(u64 *)(data + 8); + lower_num = *(u64 *)data; +#endif + if (upper_num == 0) + seq_printf(m, "0x%llx", lower_num); + else + seq_printf(m, "0x%llx%016llx", upper_num, lower_num); +} + +static void btf_int128_shift(u64 *print_num, u16 left_shift_bits, + u16 right_shift_bits) +{ + u64 upper_num, lower_num; + +#ifdef __BIG_ENDIAN_BITFIELD + upper_num = print_num[0]; + lower_num = print_num[1]; +#else + upper_num = print_num[1]; + lower_num = print_num[0]; +#endif + + /* shake out un-needed bits by shift/or operations */ + if (left_shift_bits >= 64) { + upper_num = lower_num << (left_shift_bits - 64); + lower_num = 0; + } else { + upper_num = (upper_num << left_shift_bits) | + (lower_num >> (64 - left_shift_bits)); + lower_num = lower_num << left_shift_bits; + } + + if (right_shift_bits >= 64) { + lower_num = upper_num >> (right_shift_bits - 64); + upper_num = 0; + } else { + lower_num = (lower_num >> right_shift_bits) | + (upper_num << (64 - right_shift_bits)); + upper_num = upper_num >> right_shift_bits; + } + +#ifdef __BIG_ENDIAN_BITFIELD + print_num[0] = upper_num; + print_num[1] = lower_num; +#else + print_num[0] = lower_num; + print_num[1] = upper_num; +#endif +} + +static void btf_bitfield_seq_show(void *data, u8 bits_offset, + u8 nr_bits, struct seq_file *m) { u16 left_shift_bits, right_shift_bits; - u32 int_data = btf_type_int(t); - u8 nr_bits = BTF_INT_BITS(int_data); - u8 total_bits_offset; u8 nr_copy_bytes; u8 nr_copy_bits; - u64 print_num; + u64 print_num[2] = {}; - /* - * bits_offset is at most 7. - * BTF_INT_OFFSET() cannot exceed 64 bits. - */ - total_bits_offset = bits_offset + BTF_INT_OFFSET(int_data); - data += BITS_ROUNDDOWN_BYTES(total_bits_offset); - bits_offset = BITS_PER_BYTE_MASKED(total_bits_offset); nr_copy_bits = nr_bits + bits_offset; nr_copy_bytes = BITS_ROUNDUP_BYTES(nr_copy_bits); - print_num = 0; - memcpy(&print_num, data, nr_copy_bytes); + memcpy(print_num, data, nr_copy_bytes); #ifdef __BIG_ENDIAN_BITFIELD left_shift_bits = bits_offset; #else - left_shift_bits = BITS_PER_U64 - nr_copy_bits; + left_shift_bits = BITS_PER_U128 - nr_copy_bits; #endif - right_shift_bits = BITS_PER_U64 - nr_bits; + right_shift_bits = BITS_PER_U128 - nr_bits; + + btf_int128_shift(print_num, left_shift_bits, right_shift_bits); + btf_int128_print(m, print_num); +} - print_num <<= left_shift_bits; - print_num >>= right_shift_bits; - seq_printf(m, "0x%llx", print_num); +static void btf_int_bits_seq_show(const struct btf *btf, + const struct btf_type *t, + void *data, u8 bits_offset, + struct seq_file *m) +{ + u32 int_data = btf_type_int(t); + u8 nr_bits = BTF_INT_BITS(int_data); + u8 total_bits_offset; + + /* + * bits_offset is at most 7. + * BTF_INT_OFFSET() cannot exceed 128 bits. + */ + total_bits_offset = bits_offset + BTF_INT_OFFSET(int_data); + data += BITS_ROUNDDOWN_BYTES(total_bits_offset); + bits_offset = BITS_PER_BYTE_MASKED(total_bits_offset); + btf_bitfield_seq_show(data, bits_offset, nr_bits, m); } static void btf_int_seq_show(const struct btf *btf, const struct btf_type *t, @@ -1041,6 +1342,9 @@ static void btf_int_seq_show(const struct btf *btf, const struct btf_type *t, } switch (nr_bits) { + case 128: + btf_int128_print(m, data); + break; case 64: if (sign) seq_printf(m, "%lld", *(s64 *)data); @@ -1074,6 +1378,7 @@ static const struct btf_kind_operations int_ops = { .check_meta = btf_int_check_meta, .resolve = btf_df_resolve, .check_member = btf_int_check_member, + .check_kflag_member = btf_int_check_kflag_member, .log_details = btf_int_log, .seq_show = btf_int_seq_show, }; @@ -1103,6 +1408,31 @@ static int btf_modifier_check_member(struct btf_verifier_env *env, resolved_type); } +static int btf_modifier_check_kflag_member(struct btf_verifier_env *env, + const struct btf_type *struct_type, + const struct btf_member *member, + const struct btf_type *member_type) +{ + const struct btf_type *resolved_type; + u32 resolved_type_id = member->type; + struct btf_member resolved_member; + struct btf *btf = env->btf; + + resolved_type = btf_type_id_size(btf, &resolved_type_id, NULL); + if (!resolved_type) { + btf_verifier_log_member(env, struct_type, member, + "Invalid member"); + return -EINVAL; + } + + resolved_member = *member; + resolved_member.type = resolved_type_id; + + return btf_type_ops(resolved_type)->check_kflag_member(env, struct_type, + &resolved_member, + resolved_type); +} + static int btf_ptr_check_member(struct btf_verifier_env *env, const struct btf_type *struct_type, const struct btf_member *member, @@ -1138,11 +1468,32 @@ static int btf_ref_type_check_meta(struct btf_verifier_env *env, return -EINVAL; } + if (btf_type_kflag(t)) { + btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); + return -EINVAL; + } + if (!BTF_TYPE_ID_VALID(t->type)) { btf_verifier_log_type(env, t, "Invalid type_id"); 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; @@ -1163,10 +1514,6 @@ static int btf_modifier_resolve(struct btf_verifier_env *env, return -EINVAL; } - /* "typedef void new_void", "const void"...etc */ - if (btf_type_is_void(next_type)) - goto resolved; - if (!env_type_is_resolve_sink(env, next_type) && !env_type_is_resolved(env, next_type_id)) return env_stack_push(env, next_type, next_type_id); @@ -1177,13 +1524,19 @@ static int btf_modifier_resolve(struct btf_verifier_env *env, * save us a few type-following when we use it later (e.g. in * pretty print). */ - if (!btf_type_id_size(btf, &next_type_id, &next_type_size) && - !btf_type_is_void(btf_type_id_resolve(btf, &next_type_id))) { - btf_verifier_log_type(env, v->t, "Invalid type_id"); - return -EINVAL; + if (!btf_type_id_size(btf, &next_type_id, &next_type_size)) { + if (env_type_is_resolved(env, next_type_id)) + next_type = btf_type_id_resolve(btf, &next_type_id); + + /* "typedef void new_void", "const void"...etc */ + if (!btf_type_is_void(next_type) && + !btf_type_is_fwd(next_type) && + !btf_type_is_func_proto(next_type)) { + btf_verifier_log_type(env, v->t, "Invalid type_id"); + return -EINVAL; + } } -resolved: env_stack_pop_resolved(env, next_type_id, next_type_size); return 0; @@ -1196,7 +1549,6 @@ static int btf_ptr_resolve(struct btf_verifier_env *env, const struct btf_type *t = v->t; u32 next_type_id = t->type; struct btf *btf = env->btf; - u32 next_type_size = 0; next_type = btf_type_by_id(btf, next_type_id); if (!next_type) { @@ -1204,10 +1556,6 @@ static int btf_ptr_resolve(struct btf_verifier_env *env, return -EINVAL; } - /* "void *" */ - if (btf_type_is_void(next_type)) - goto resolved; - if (!env_type_is_resolve_sink(env, next_type) && !env_type_is_resolved(env, next_type_id)) return env_stack_push(env, next_type, next_type_id); @@ -1234,13 +1582,18 @@ static int btf_ptr_resolve(struct btf_verifier_env *env, resolved_type_id); } - if (!btf_type_id_size(btf, &next_type_id, &next_type_size) && - !btf_type_is_void(btf_type_id_resolve(btf, &next_type_id))) { - btf_verifier_log_type(env, v->t, "Invalid type_id"); - return -EINVAL; + if (!btf_type_id_size(btf, &next_type_id, NULL)) { + if (env_type_is_resolved(env, next_type_id)) + next_type = btf_type_id_resolve(btf, &next_type_id); + + if (!btf_type_is_void(next_type) && + !btf_type_is_fwd(next_type) && + !btf_type_is_func_proto(next_type)) { + btf_verifier_log_type(env, v->t, "Invalid type_id"); + return -EINVAL; + } } -resolved: env_stack_pop_resolved(env, next_type_id, 0); return 0; @@ -1274,6 +1627,7 @@ static struct btf_kind_operations modifier_ops = { .check_meta = btf_ref_type_check_meta, .resolve = btf_modifier_resolve, .check_member = btf_modifier_check_member, + .check_kflag_member = btf_modifier_check_kflag_member, .log_details = btf_ref_type_log, .seq_show = btf_modifier_seq_show, }; @@ -1282,6 +1636,7 @@ static struct btf_kind_operations ptr_ops = { .check_meta = btf_ref_type_check_meta, .resolve = btf_ptr_resolve, .check_member = btf_ptr_check_member, + .check_kflag_member = btf_generic_check_kflag_member, .log_details = btf_ref_type_log, .seq_show = btf_ptr_seq_show, }; @@ -1300,16 +1655,30 @@ 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; } +static void btf_fwd_type_log(struct btf_verifier_env *env, + const struct btf_type *t) +{ + btf_verifier_log(env, "%s", btf_type_kflag(t) ? "union" : "struct"); +} + static struct btf_kind_operations fwd_ops = { .check_meta = btf_fwd_check_meta, .resolve = btf_df_resolve, .check_member = btf_df_check_member, - .log_details = btf_ref_type_log, + .check_kflag_member = btf_df_check_kflag_member, + .log_details = btf_fwd_type_log, .seq_show = btf_df_seq_show, }; @@ -1356,11 +1725,22 @@ 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; } + if (btf_type_kflag(t)) { + btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); + return -EINVAL; + } + if (t->size) { btf_verifier_log_type(env, t, "size != 0"); return -EINVAL; @@ -1396,7 +1776,7 @@ static int btf_array_resolve(struct btf_verifier_env *env, /* Check array->index_type */ index_type_id = array->index_type; index_type = btf_type_by_id(btf, index_type_id); - if (btf_type_is_void_or_null(index_type)) { + if (btf_type_nosize_or_null(index_type)) { btf_verifier_log_type(env, v->t, "Invalid index"); return -EINVAL; } @@ -1415,7 +1795,7 @@ static int btf_array_resolve(struct btf_verifier_env *env, /* Check array->type */ elem_type_id = array->type; elem_type = btf_type_by_id(btf, elem_type_id); - if (btf_type_is_void_or_null(elem_type)) { + if (btf_type_nosize_or_null(elem_type)) { btf_verifier_log_type(env, v->t, "Invalid elem"); return -EINVAL; @@ -1484,6 +1864,7 @@ static struct btf_kind_operations array_ops = { .check_meta = btf_array_check_meta, .resolve = btf_array_resolve, .check_member = btf_array_check_member, + .check_kflag_member = btf_generic_check_kflag_member, .log_details = btf_array_log, .seq_show = btf_array_seq_show, }; @@ -1522,6 +1903,7 @@ static s32 btf_struct_check_meta(struct btf_verifier_env *env, u32 meta_needed, last_offset; struct btf *btf = env->btf; u32 struct_size = t->size; + u32 offset; u16 i; meta_needed = btf_type_vlen(t) * sizeof(*member); @@ -1532,6 +1914,13 @@ 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; @@ -1543,6 +1932,12 @@ 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, @@ -1550,7 +1945,8 @@ static s32 btf_struct_check_meta(struct btf_verifier_env *env, return -EINVAL; } - if (is_union && member->offset) { + offset = btf_member_bit_offset(t, member); + if (is_union && offset) { btf_verifier_log_member(env, t, member, "Invalid member bits_offset"); return -EINVAL; @@ -1560,20 +1956,20 @@ static s32 btf_struct_check_meta(struct btf_verifier_env *env, * ">" instead of ">=" because the last member could be * "char a[0];" */ - if (last_offset > member->offset) { + if (last_offset > offset) { btf_verifier_log_member(env, t, member, "Invalid member bits_offset"); return -EINVAL; } - if (BITS_ROUNDUP_BYTES(member->offset) > struct_size) { + if (BITS_ROUNDUP_BYTES(offset) > struct_size) { btf_verifier_log_member(env, t, member, - "Memmber bits_offset exceeds its struct size"); + "Member bits_offset exceeds its struct size"); return -EINVAL; } btf_verifier_log_member(env, t, member, NULL); - last_offset = member->offset; + last_offset = offset; } return meta_needed; @@ -1603,9 +1999,14 @@ static int btf_struct_resolve(struct btf_verifier_env *env, last_member_type = btf_type_by_id(env->btf, last_member_type_id); - err = btf_type_ops(last_member_type)->check_member(env, v->t, - last_member, - last_member_type); + if (btf_type_kflag(v->t)) + err = btf_type_ops(last_member_type)->check_kflag_member(env, v->t, + last_member, + last_member_type); + else + err = btf_type_ops(last_member_type)->check_member(env, v->t, + last_member, + last_member_type); if (err) return err; } @@ -1615,7 +2016,7 @@ static int btf_struct_resolve(struct btf_verifier_env *env, const struct btf_type *member_type = btf_type_by_id(env->btf, member_type_id); - if (btf_type_is_void_or_null(member_type)) { + if (btf_type_nosize_or_null(member_type)) { btf_verifier_log_member(env, v->t, member, "Invalid member"); return -EINVAL; @@ -1627,9 +2028,14 @@ static int btf_struct_resolve(struct btf_verifier_env *env, return env_stack_push(env, member_type, member_type_id); } - err = btf_type_ops(member_type)->check_member(env, v->t, - member, - member_type); + if (btf_type_kflag(v->t)) + err = btf_type_ops(member_type)->check_kflag_member(env, v->t, + member, + member_type); + else + err = btf_type_ops(member_type)->check_member(env, v->t, + member, + member_type); if (err) return err; } @@ -1645,6 +2051,43 @@ static void btf_struct_log(struct btf_verifier_env *env, btf_verifier_log(env, "size=%u vlen=%u", t->size, btf_type_vlen(t)); } +/* find 'struct bpf_spin_lock' in map value. + * return >= 0 offset if found + * and < 0 in case of error + */ +int btf_find_spin_lock(const struct btf *btf, const struct btf_type *t) +{ + const struct btf_member *member; + u32 i, off = -ENOENT; + + if (!__btf_type_is_struct(t)) + return -EINVAL; + + for_each_member(i, t, member) { + const struct btf_type *member_type = btf_type_by_id(btf, + member->type); + if (!__btf_type_is_struct(member_type)) + continue; + if (member_type->size != sizeof(struct bpf_spin_lock)) + continue; + if (strcmp(__btf_name_by_offset(btf, member_type->name_off), + "bpf_spin_lock")) + continue; + if (off != -ENOENT) + /* only one 'struct bpf_spin_lock' is allowed */ + return -E2BIG; + off = btf_member_bit_offset(t, member); + if (off % 8) + /* valid C code cannot generate such BTF */ + return -EINVAL; + off /= 8; + if (off % __alignof__(struct bpf_spin_lock)) + /* valid struct bpf_spin_lock will be 4 byte aligned */ + return -EINVAL; + } + return off; +} + static void btf_struct_seq_show(const struct btf *btf, const struct btf_type *t, u32 type_id, void *data, u8 bits_offset, struct seq_file *m) @@ -1657,17 +2100,26 @@ static void btf_struct_seq_show(const struct btf *btf, const struct btf_type *t, for_each_member(i, t, member) { const struct btf_type *member_type = btf_type_by_id(btf, member->type); - u32 member_offset = member->offset; - u32 bytes_offset = BITS_ROUNDDOWN_BYTES(member_offset); - u8 bits8_offset = BITS_PER_BYTE_MASKED(member_offset); const struct btf_kind_operations *ops; + u32 member_offset, bitfield_size; + u32 bytes_offset; + u8 bits8_offset; if (i) seq_puts(m, seq); - ops = btf_type_ops(member_type); - ops->seq_show(btf, member_type, member->type, - data + bytes_offset, bits8_offset, m); + member_offset = btf_member_bit_offset(t, member); + bitfield_size = btf_member_bitfield_size(t, member); + bytes_offset = BITS_ROUNDDOWN_BYTES(member_offset); + bits8_offset = BITS_PER_BYTE_MASKED(member_offset); + if (bitfield_size) { + btf_bitfield_seq_show(data + bytes_offset, bits8_offset, + bitfield_size, m); + } else { + ops = btf_type_ops(member_type); + ops->seq_show(btf, member_type, member->type, + data + bytes_offset, bits8_offset, m); + } } seq_puts(m, "}"); } @@ -1676,6 +2128,7 @@ static struct btf_kind_operations struct_ops = { .check_meta = btf_struct_check_meta, .resolve = btf_struct_resolve, .check_member = btf_struct_check_member, + .check_kflag_member = btf_generic_check_kflag_member, .log_details = btf_struct_log, .seq_show = btf_struct_seq_show, }; @@ -1705,6 +2158,41 @@ static int btf_enum_check_member(struct btf_verifier_env *env, return 0; } +static int btf_enum_check_kflag_member(struct btf_verifier_env *env, + const struct btf_type *struct_type, + const struct btf_member *member, + const struct btf_type *member_type) +{ + u32 struct_bits_off, nr_bits, bytes_end, struct_size; + u32 int_bitsize = sizeof(int) * BITS_PER_BYTE; + + struct_bits_off = BTF_MEMBER_BIT_OFFSET(member->offset); + nr_bits = BTF_MEMBER_BITFIELD_SIZE(member->offset); + if (!nr_bits) { + if (BITS_PER_BYTE_MASKED(struct_bits_off)) { + btf_verifier_log_member(env, struct_type, member, + "Member is not byte aligned"); + return -EINVAL; + } + + nr_bits = int_bitsize; + } else if (nr_bits > int_bitsize) { + btf_verifier_log_member(env, struct_type, member, + "Invalid member bitfield_size"); + return -EINVAL; + } + + struct_size = struct_type->size; + bytes_end = BITS_ROUNDUP_BYTES(struct_bits_off + nr_bits); + if (struct_size < bytes_end) { + btf_verifier_log_member(env, struct_type, member, + "Member exceeds struct_size"); + return -EINVAL; + } + + return 0; +} + static s32 btf_enum_check_meta(struct btf_verifier_env *env, const struct btf_type *t, u32 meta_left) @@ -1724,12 +2212,24 @@ static s32 btf_enum_check_meta(struct btf_verifier_env *env, return -EINVAL; } + if (btf_type_kflag(t)) { + btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); + return -EINVAL; + } + if (t->size != sizeof(int)) { btf_verifier_log_type(env, t, "Expected size:%zu", sizeof(int)); 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++) { @@ -1739,8 +2239,16 @@ 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), + __btf_name_by_offset(btf, enums[i].name_off), enums[i].val); } @@ -1764,7 +2272,8 @@ static void btf_enum_seq_show(const struct btf *btf, const struct btf_type *t, for (i = 0; i < nr_enums; i++) { if (v == enums[i].val) { seq_printf(m, "%s", - btf_name_by_offset(btf, enums[i].name_off)); + __btf_name_by_offset(btf, + enums[i].name_off)); return; } } @@ -1776,10 +2285,249 @@ static struct btf_kind_operations enum_ops = { .check_meta = btf_enum_check_meta, .resolve = btf_df_resolve, .check_member = btf_enum_check_member, + .check_kflag_member = btf_enum_check_kflag_member, .log_details = btf_enum_log, .seq_show = btf_enum_seq_show, }; +static s32 btf_func_proto_check_meta(struct btf_verifier_env *env, + const struct btf_type *t, + u32 meta_left) +{ + u32 meta_needed = btf_type_vlen(t) * sizeof(struct btf_param); + + if (meta_left < meta_needed) { + btf_verifier_log_basic(env, t, + "meta_left:%u meta_needed:%u", + meta_left, meta_needed); + return -EINVAL; + } + + if (t->name_off) { + btf_verifier_log_type(env, t, "Invalid name"); + return -EINVAL; + } + + if (btf_type_kflag(t)) { + btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); + return -EINVAL; + } + + btf_verifier_log_type(env, t, NULL); + + return meta_needed; +} + +static void btf_func_proto_log(struct btf_verifier_env *env, + const struct btf_type *t) +{ + const struct btf_param *args = (const struct btf_param *)(t + 1); + u16 nr_args = btf_type_vlen(t), i; + + btf_verifier_log(env, "return=%u args=(", t->type); + if (!nr_args) { + btf_verifier_log(env, "void"); + goto done; + } + + if (nr_args == 1 && !args[0].type) { + /* Only one vararg */ + btf_verifier_log(env, "vararg"); + goto done; + } + + btf_verifier_log(env, "%u %s", args[0].type, + __btf_name_by_offset(env->btf, + args[0].name_off)); + for (i = 1; i < nr_args - 1; i++) + btf_verifier_log(env, ", %u %s", args[i].type, + __btf_name_by_offset(env->btf, + args[i].name_off)); + + if (nr_args > 1) { + const struct btf_param *last_arg = &args[nr_args - 1]; + + if (last_arg->type) + btf_verifier_log(env, ", %u %s", last_arg->type, + __btf_name_by_offset(env->btf, + last_arg->name_off)); + else + btf_verifier_log(env, ", vararg"); + } + +done: + btf_verifier_log(env, ")"); +} + +static struct btf_kind_operations func_proto_ops = { + .check_meta = btf_func_proto_check_meta, + .resolve = btf_df_resolve, + /* + * BTF_KIND_FUNC_PROTO cannot be directly referred by + * a struct's member. + * + * It should be a funciton pointer instead. + * (i.e. struct's member -> BTF_KIND_PTR -> BTF_KIND_FUNC_PROTO) + * + * Hence, there is no btf_func_check_member(). + */ + .check_member = btf_df_check_member, + .check_kflag_member = btf_df_check_kflag_member, + .log_details = btf_func_proto_log, + .seq_show = btf_df_seq_show, +}; + +static s32 btf_func_check_meta(struct btf_verifier_env *env, + const struct btf_type *t, + u32 meta_left) +{ + if (!t->name_off || + !btf_name_valid_identifier(env->btf, 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; + } + + if (btf_type_kflag(t)) { + btf_verifier_log_type(env, t, "Invalid btf_info kind_flag"); + return -EINVAL; + } + + btf_verifier_log_type(env, t, NULL); + + return 0; +} + +static struct btf_kind_operations func_ops = { + .check_meta = btf_func_check_meta, + .resolve = btf_df_resolve, + .check_member = btf_df_check_member, + .check_kflag_member = btf_df_check_kflag_member, + .log_details = btf_ref_type_log, + .seq_show = btf_df_seq_show, +}; + +static int btf_func_proto_check(struct btf_verifier_env *env, + const struct btf_type *t) +{ + const struct btf_type *ret_type; + const struct btf_param *args; + const struct btf *btf; + u16 nr_args, i; + int err; + + btf = env->btf; + args = (const struct btf_param *)(t + 1); + nr_args = btf_type_vlen(t); + + /* Check func return type which could be "void" (t->type == 0) */ + if (t->type) { + u32 ret_type_id = t->type; + + ret_type = btf_type_by_id(btf, ret_type_id); + if (!ret_type) { + btf_verifier_log_type(env, t, "Invalid return type"); + return -EINVAL; + } + + if (btf_type_needs_resolve(ret_type) && + !env_type_is_resolved(env, ret_type_id)) { + err = btf_resolve(env, ret_type, ret_type_id); + if (err) + return err; + } + + /* Ensure the return type is a type that has a size */ + if (!btf_type_id_size(btf, &ret_type_id, NULL)) { + btf_verifier_log_type(env, t, "Invalid return type"); + return -EINVAL; + } + } + + if (!nr_args) + return 0; + + /* Last func arg type_id could be 0 if it is a vararg */ + if (!args[nr_args - 1].type) { + if (args[nr_args - 1].name_off) { + btf_verifier_log_type(env, t, "Invalid arg#%u", + nr_args); + return -EINVAL; + } + nr_args--; + } + + err = 0; + for (i = 0; i < nr_args; i++) { + const struct btf_type *arg_type; + u32 arg_type_id; + + arg_type_id = args[i].type; + arg_type = btf_type_by_id(btf, arg_type_id); + if (!arg_type) { + btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1); + err = -EINVAL; + break; + } + + if (args[i].name_off && + (!btf_name_offset_valid(btf, args[i].name_off) || + !btf_name_valid_identifier(btf, args[i].name_off))) { + btf_verifier_log_type(env, t, + "Invalid arg#%u", i + 1); + err = -EINVAL; + break; + } + + if (btf_type_needs_resolve(arg_type) && + !env_type_is_resolved(env, arg_type_id)) { + err = btf_resolve(env, arg_type, arg_type_id); + if (err) + break; + } + + if (!btf_type_id_size(btf, &arg_type_id, NULL)) { + btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1); + err = -EINVAL; + break; + } + } + + return err; +} + +static int btf_func_check(struct btf_verifier_env *env, + const struct btf_type *t) +{ + const struct btf_type *proto_type; + const struct btf_param *args; + const struct btf *btf; + u16 nr_args, i; + + btf = env->btf; + proto_type = btf_type_by_id(btf, t->type); + + if (!proto_type || !btf_type_is_func_proto(proto_type)) { + btf_verifier_log_type(env, t, "Invalid type_id"); + return -EINVAL; + } + + args = (const struct btf_param *)(proto_type + 1); + nr_args = btf_type_vlen(proto_type); + for (i = 0; i < nr_args; i++) { + if (!args[i].name_off && args[i].type) { + btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1); + return -EINVAL; + } + } + + return 0; +} + static const struct btf_kind_operations * const kind_ops[NR_BTF_KINDS] = { [BTF_KIND_INT] = &int_ops, [BTF_KIND_PTR] = &ptr_ops, @@ -1792,6 +2540,8 @@ static const struct btf_kind_operations * const kind_ops[NR_BTF_KINDS] = { [BTF_KIND_VOLATILE] = &modifier_ops, [BTF_KIND_CONST] = &modifier_ops, [BTF_KIND_RESTRICT] = &modifier_ops, + [BTF_KIND_FUNC] = &func_ops, + [BTF_KIND_FUNC_PROTO] = &func_proto_ops, }; static s32 btf_check_meta(struct btf_verifier_env *env, @@ -1863,30 +2613,6 @@ static int btf_check_all_metas(struct btf_verifier_env *env) return 0; } -static int btf_resolve(struct btf_verifier_env *env, - const struct btf_type *t, u32 type_id) -{ - const struct resolve_vertex *v; - int err = 0; - - env->resolve_mode = RESOLVE_TBD; - env_stack_push(env, t, type_id); - while (!err && (v = env_stack_peak(env))) { - env->log_type_id = v->type_id; - err = btf_type_ops(v->t)->resolve(env, v); - } - - env->log_type_id = type_id; - if (err == -E2BIG) - btf_verifier_log_type(env, t, - "Exceeded max resolving depth:%u", - MAX_RESOLVE_DEPTH); - else if (err == -EEXIST) - btf_verifier_log_type(env, t, "Loop detected"); - - return err; -} - static bool btf_resolve_valid(struct btf_verifier_env *env, const struct btf_type *t, u32 type_id) @@ -1920,6 +2646,39 @@ static bool btf_resolve_valid(struct btf_verifier_env *env, return false; } +static int btf_resolve(struct btf_verifier_env *env, + const struct btf_type *t, u32 type_id) +{ + u32 save_log_type_id = env->log_type_id; + const struct resolve_vertex *v; + int err = 0; + + env->resolve_mode = RESOLVE_TBD; + env_stack_push(env, t, type_id); + while (!err && (v = env_stack_peak(env))) { + env->log_type_id = v->type_id; + err = btf_type_ops(v->t)->resolve(env, v); + } + + env->log_type_id = type_id; + if (err == -E2BIG) { + btf_verifier_log_type(env, t, + "Exceeded max resolving depth:%u", + MAX_RESOLVE_DEPTH); + } else if (err == -EEXIST) { + btf_verifier_log_type(env, t, "Loop detected"); + } + + /* Final sanity check */ + if (!err && !btf_resolve_valid(env, t, type_id)) { + btf_verifier_log_type(env, t, "Invalid resolve state"); + err = -EINVAL; + } + + env->log_type_id = save_log_type_id; + return err; +} + static int btf_check_all_types(struct btf_verifier_env *env) { struct btf *btf = env->btf; @@ -1942,10 +2701,16 @@ static int btf_check_all_types(struct btf_verifier_env *env) return err; } - if (btf_type_needs_resolve(t) && - !btf_resolve_valid(env, t, type_id)) { - btf_verifier_log_type(env, t, "Invalid resolve state"); - return -EINVAL; + if (btf_type_is_func_proto(t)) { + err = btf_func_proto_check(env, t); + if (err) + return err; + } + + if (btf_type_is_func(t)) { + err = btf_func_check(env, t); + if (err) + return err; } } @@ -2067,56 +2832,47 @@ static int btf_check_sec_info(struct btf_verifier_env *env, return 0; } -static int btf_parse_hdr(struct btf_verifier_env *env, void __user *btf_data, - u32 btf_data_size) +static int btf_parse_hdr(struct btf_verifier_env *env) { + u32 hdr_len, hdr_copy, btf_data_size; const struct btf_header *hdr; - u32 hdr_len, hdr_copy; - /* - * Minimal part of the "struct btf_header" that - * contains the hdr_len. - */ - struct btf_min_header { - u16 magic; - u8 version; - u8 flags; - u32 hdr_len; - } __user *min_hdr; struct btf *btf; int err; btf = env->btf; - min_hdr = btf_data; + btf_data_size = btf->data_size; - if (btf_data_size < sizeof(*min_hdr)) { + if (btf_data_size < + offsetof(struct btf_header, hdr_len) + sizeof(hdr->hdr_len)) { btf_verifier_log(env, "hdr_len not found"); return -EINVAL; } - if (get_user(hdr_len, &min_hdr->hdr_len)) - return -EFAULT; - + hdr = btf->data; + hdr_len = hdr->hdr_len; if (btf_data_size < hdr_len) { btf_verifier_log(env, "btf_header not found"); return -EINVAL; } - err = bpf_check_uarg_tail_zero(btf_data, sizeof(btf->hdr), hdr_len); - if (err) { - if (err == -E2BIG) - btf_verifier_log(env, "Unsupported btf_header"); - return err; + /* Ensure the unsupported header fields are zero */ + if (hdr_len > sizeof(btf->hdr)) { + u8 *expected_zero = btf->data + sizeof(btf->hdr); + u8 *end = btf->data + hdr_len; + + for (; expected_zero < end; expected_zero++) { + if (*expected_zero) { + btf_verifier_log(env, "Unsupported btf_header"); + return -E2BIG; + } + } } hdr_copy = min_t(u32, hdr_len, sizeof(btf->hdr)); - if (copy_from_user(&btf->hdr, btf_data, hdr_copy)) - return -EFAULT; + memcpy(&btf->hdr, btf->data, hdr_copy); hdr = &btf->hdr; - if (hdr->hdr_len != hdr_len) - return -EINVAL; - btf_verifier_log_hdr(env, btf_data_size); if (hdr->magic != BTF_MAGIC) { @@ -2186,10 +2942,6 @@ static struct btf *btf_parse(void __user *btf_data, u32 btf_data_size, } env->btf = btf; - err = btf_parse_hdr(env, btf_data, btf_data_size); - if (err) - goto errout; - data = kvmalloc(btf_data_size, GFP_KERNEL | __GFP_NOWARN); if (!data) { err = -ENOMEM; @@ -2198,13 +2950,18 @@ static struct btf *btf_parse(void __user *btf_data, u32 btf_data_size, btf->data = data; btf->data_size = btf_data_size; - btf->nohdr_data = btf->data + btf->hdr.hdr_len; if (copy_from_user(data, btf_data, btf_data_size)) { err = -EFAULT; goto errout; } + err = btf_parse_hdr(env); + if (err) + goto errout; + + btf->nohdr_data = btf->data + btf->hdr.hdr_len; + err = btf_parse_str_sec(env); if (err) goto errout; |