diff options
| -rw-r--r-- | tools/lib/bpf/btf.h | 19 | ||||
| -rw-r--r-- | tools/lib/bpf/btf_dump.c | 819 | ||||
| -rw-r--r-- | tools/lib/bpf/libbpf.map | 1 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/prog_tests/btf_dump.c | 598 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/test_progs.h | 12 |
5 files changed, 1444 insertions, 5 deletions
diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h index b54f1c3ebd57..374e9f15de2e 100644 --- a/tools/lib/bpf/btf.h +++ b/tools/lib/bpf/btf.h @@ -184,6 +184,25 @@ LIBBPF_API int btf_dump__emit_type_decl(struct btf_dump *d, __u32 id, const struct btf_dump_emit_type_decl_opts *opts); + +struct btf_dump_type_data_opts { + /* size of this struct, for forward/backward compatibility */ + size_t sz; + const char *indent_str; + int indent_level; + /* below match "show" flags for bpf_show_snprintf() */ + bool compact; /* no newlines/indentation */ + bool skip_names; /* skip member/type names */ + bool emit_zeroes; /* show 0-valued fields */ + size_t :0; +}; +#define btf_dump_type_data_opts__last_field emit_zeroes + +LIBBPF_API int +btf_dump__dump_type_data(struct btf_dump *d, __u32 id, + const void *data, size_t data_sz, + const struct btf_dump_type_data_opts *opts); + /* * A set of helpers for easier BTF types handling */ diff --git a/tools/lib/bpf/btf_dump.c b/tools/lib/bpf/btf_dump.c index 5dc6b5172bb3..929cf931ed66 100644 --- a/tools/lib/bpf/btf_dump.c +++ b/tools/lib/bpf/btf_dump.c @@ -10,6 +10,8 @@ #include <stddef.h> #include <stdlib.h> #include <string.h> +#include <ctype.h> +#include <endian.h> #include <errno.h> #include <linux/err.h> #include <linux/btf.h> @@ -53,6 +55,26 @@ struct btf_dump_type_aux_state { __u8 referenced: 1; }; +/* indent string length; one indent string is added for each indent level */ +#define BTF_DATA_INDENT_STR_LEN 32 + +/* + * Common internal data for BTF type data dump operations. + */ +struct btf_dump_data { + const void *data_end; /* end of valid data to show */ + bool compact; + bool skip_names; + bool emit_zeroes; + __u8 indent_lvl; /* base indent level */ + char indent_str[BTF_DATA_INDENT_STR_LEN]; + /* below are used during iteration */ + int depth; + bool is_array_member; + bool is_array_terminated; + bool is_array_char; +}; + struct btf_dump { const struct btf *btf; const struct btf_ext *btf_ext; @@ -60,6 +82,7 @@ struct btf_dump { struct btf_dump_opts opts; int ptr_sz; bool strip_mods; + bool skip_anon_defs; int last_id; /* per-type auxiliary state */ @@ -89,6 +112,10 @@ struct btf_dump { * name occurrences */ struct hashmap *ident_names; + /* + * data for typed display; allocated if needed. + */ + struct btf_dump_data *typed_dump; }; static size_t str_hash_fn(const void *key, void *ctx) @@ -765,11 +792,11 @@ static void btf_dump_emit_type(struct btf_dump *d, __u32 id, __u32 cont_id) break; case BTF_KIND_FUNC_PROTO: { const struct btf_param *p = btf_params(t); - __u16 vlen = btf_vlen(t); + __u16 n = btf_vlen(t); int i; btf_dump_emit_type(d, t->type, cont_id); - for (i = 0; i < vlen; i++, p++) + for (i = 0; i < n; i++, p++) btf_dump_emit_type(d, p->type, cont_id); break; @@ -852,8 +879,9 @@ static void btf_dump_emit_bit_padding(const struct btf_dump *d, static void btf_dump_emit_struct_fwd(struct btf_dump *d, __u32 id, const struct btf_type *t) { - btf_dump_printf(d, "%s %s", + btf_dump_printf(d, "%s%s%s", btf_is_struct(t) ? "struct" : "union", + t->name_off ? " " : "", btf_dump_type_name(d, id)); } @@ -1259,7 +1287,7 @@ static void btf_dump_emit_type_chain(struct btf_dump *d, case BTF_KIND_UNION: btf_dump_emit_mods(d, decls); /* inline anonymous struct/union */ - if (t->name_off == 0) + if (t->name_off == 0 && !d->skip_anon_defs) btf_dump_emit_struct_def(d, id, t, lvl); else btf_dump_emit_struct_fwd(d, id, t); @@ -1267,7 +1295,7 @@ static void btf_dump_emit_type_chain(struct btf_dump *d, case BTF_KIND_ENUM: btf_dump_emit_mods(d, decls); /* inline anonymous enum */ - if (t->name_off == 0) + if (t->name_off == 0 && !d->skip_anon_defs) btf_dump_emit_enum_def(d, id, t, lvl); else btf_dump_emit_enum_fwd(d, id, t); @@ -1392,6 +1420,39 @@ static void btf_dump_emit_type_chain(struct btf_dump *d, btf_dump_emit_name(d, fname, last_was_ptr); } +/* show type name as (type_name) */ +static void btf_dump_emit_type_cast(struct btf_dump *d, __u32 id, + bool top_level) +{ + const struct btf_type *t; + + /* for array members, we don't bother emitting type name for each + * member to avoid the redundancy of + * .name = (char[4])[(char)'f',(char)'o',(char)'o',] + */ + if (d->typed_dump->is_array_member) + return; + + /* avoid type name specification for variable/section; it will be done + * for the associated variable value(s). + */ + t = btf__type_by_id(d->btf, id); + if (btf_is_var(t) || btf_is_datasec(t)) + return; + + if (top_level) + btf_dump_printf(d, "("); + + d->skip_anon_defs = true; + d->strip_mods = true; + btf_dump_emit_type_decl(d, id, "", 0); + d->strip_mods = false; + d->skip_anon_defs = false; + + if (top_level) + btf_dump_printf(d, ")"); +} + /* return number of duplicates (occurrences) of a given name */ static size_t btf_dump_name_dups(struct btf_dump *d, struct hashmap *name_map, const char *orig_name) @@ -1442,3 +1503,751 @@ static const char *btf_dump_ident_name(struct btf_dump *d, __u32 id) { return btf_dump_resolve_name(d, id, d->ident_names); } + +static int btf_dump_dump_type_data(struct btf_dump *d, + const char *fname, + const struct btf_type *t, + __u32 id, + const void *data, + __u8 bits_offset, + __u8 bit_sz); + +static const char *btf_dump_data_newline(struct btf_dump *d) +{ + return d->typed_dump->compact || d->typed_dump->depth == 0 ? "" : "\n"; +} + +static const char *btf_dump_data_delim(struct btf_dump *d) +{ + return d->typed_dump->depth == 0 ? "" : ","; +} + +static void btf_dump_data_pfx(struct btf_dump *d) +{ + int i, lvl = d->typed_dump->indent_lvl + d->typed_dump->depth; + + if (d->typed_dump->compact) + return; + + for (i = 0; i < lvl; i++) + btf_dump_printf(d, "%s", d->typed_dump->indent_str); +} + +/* A macro is used here as btf_type_value[s]() appends format specifiers + * to the format specifier passed in; these do the work of appending + * delimiters etc while the caller simply has to specify the type values + * in the format specifier + value(s). + */ +#define btf_dump_type_values(d, fmt, ...) \ + btf_dump_printf(d, fmt "%s%s", \ + ##__VA_ARGS__, \ + btf_dump_data_delim(d), \ + btf_dump_data_newline(d)) + +static int btf_dump_unsupported_data(struct btf_dump *d, + const struct btf_type *t, + __u32 id) +{ + btf_dump_printf(d, "<unsupported kind:%u>", btf_kind(t)); + return -ENOTSUP; +} + +static void btf_dump_int128(struct btf_dump *d, + const struct btf_type *t, + const void *data) +{ + __int128 num = *(__int128 *)data; + + if ((num >> 64) == 0) + btf_dump_type_values(d, "0x%llx", (long long)num); + else + btf_dump_type_values(d, "0x%llx%016llx", (long long)num >> 32, + (long long)num); +} + +static unsigned __int128 btf_dump_bitfield_get_data(struct btf_dump *d, + const struct btf_type *t, + const void *data, + __u8 bits_offset, + __u8 bit_sz) +{ + __u16 left_shift_bits, right_shift_bits; + __u8 nr_copy_bits, nr_copy_bytes; + unsigned __int128 num = 0, ret; + const __u8 *bytes = data; + int i; + + /* Bitfield value retrieval is done in two steps; first relevant bytes are + * stored in num, then we left/right shift num to eliminate irrelevant bits. + */ + nr_copy_bits = bit_sz + bits_offset; + nr_copy_bytes = t->size; +#if __BYTE_ORDER == __LITTLE_ENDIAN + for (i = nr_copy_bytes - 1; i >= 0; i--) + num = num * 256 + bytes[i]; +#elif __BYTE_ORDER == __BIG_ENDIAN + for (i = 0; i < nr_copy_bytes; i++) + num = num * 256 + bytes[i]; +#else +# error "Unrecognized __BYTE_ORDER__" +#endif + left_shift_bits = 128 - nr_copy_bits; + right_shift_bits = 128 - bit_sz; + + ret = (num << left_shift_bits) >> right_shift_bits; + + return ret; +} + +static int btf_dump_bitfield_check_zero(struct btf_dump *d, + const struct btf_type *t, + const void *data, + __u8 bits_offset, + __u8 bit_sz) +{ + __int128 check_num; + + check_num = btf_dump_bitfield_get_data(d, t, data, bits_offset, bit_sz); + if (check_num == 0) + return -ENODATA; + return 0; +} + +static int btf_dump_bitfield_data(struct btf_dump *d, + const struct btf_type *t, + const void *data, + __u8 bits_offset, + __u8 bit_sz) +{ + unsigned __int128 print_num; + + print_num = btf_dump_bitfield_get_data(d, t, data, bits_offset, bit_sz); + btf_dump_int128(d, t, &print_num); + + return 0; +} + +/* ints, floats and ptrs */ +static int btf_dump_base_type_check_zero(struct btf_dump *d, + const struct btf_type *t, + __u32 id, + const void *data) +{ + static __u8 bytecmp[16] = {}; + int nr_bytes; + + /* For pointer types, pointer size is not defined on a per-type basis. + * On dump creation however, we store the pointer size. + */ + if (btf_kind(t) == BTF_KIND_PTR) + nr_bytes = d->ptr_sz; + else + nr_bytes = t->size; + + if (nr_bytes < 1 || nr_bytes > 16) { + pr_warn("unexpected size %d for id [%u]\n", nr_bytes, id); + return -EINVAL; + } + + if (memcmp(data, bytecmp, nr_bytes) == 0) + return -ENODATA; + return 0; +} + +static int btf_dump_int_data(struct btf_dump *d, + const struct btf_type *t, + __u32 type_id, + const void *data, + __u8 bits_offset) +{ + __u8 encoding = btf_int_encoding(t); + bool sign = encoding & BTF_INT_SIGNED; + int sz = t->size; + + if (sz == 0) { + pr_warn("unexpected size %d for id [%u]\n", sz, type_id); + return -EINVAL; + } + + /* handle packed int data - accesses of integers not aligned on + * int boundaries can cause problems on some platforms. + */ + if (((uintptr_t)data) % sz) + return btf_dump_bitfield_data(d, t, data, 0, 0); + + switch (sz) { + case 16: + btf_dump_int128(d, t, data); + break; + case 8: + if (sign) + btf_dump_type_values(d, "%lld", *(long long *)data); + else + btf_dump_type_values(d, "%llu", *(unsigned long long *)data); + break; + case 4: + if (sign) + btf_dump_type_values(d, "%d", *(__s32 *)data); + else + btf_dump_type_values(d, "%u", *(__u32 *)data); + break; + case 2: + if (sign) + btf_dump_type_values(d, "%d", *(__s16 *)data); + else + btf_dump_type_values(d, "%u", *(__u16 *)data); + break; + case 1: + if (d->typed_dump->is_array_char) { + /* check for null terminator */ + if (d->typed_dump->is_array_terminated) + break; + if (*(char *)data == '\0') { + d->typed_dump->is_array_terminated = true; + break; + } + if (isprint(*(char *)data)) { + btf_dump_type_values(d, "'%c'", *(char *)data); + break; + } + } + if (sign) + btf_dump_type_values(d, "%d", *(__s8 *)data); + else + btf_dump_type_values(d, "%u", *(__u8 *)data); + break; + default: + pr_warn("unexpected sz %d for id [%u]\n", sz, type_id); + return -EINVAL; + } + return 0; +} + +union float_data { + long double ld; + double d; + float f; +}; + +static int btf_dump_float_data(struct btf_dump *d, + const struct btf_type *t, + __u32 type_id, + const void *data) +{ + const union float_data *flp = data; + union float_data fl; + int sz = t->size; + + /* handle unaligned data; copy to local union */ + if (((uintptr_t)data) % sz) { + memcpy(&fl, data, sz); + flp = &fl; + } + + switch (sz) { + case 16: + btf_dump_type_values(d, "%Lf", flp->ld); + break; + case 8: + btf_dump_type_values(d, "%lf", flp->d); + break; + case 4: + btf_dump_type_values(d, "%f", flp->f); + break; + default: + pr_warn("unexpected size %d for id [%u]\n", sz, type_id); + return -EINVAL; + } + return 0; +} + +static int btf_dump_var_data(struct btf_dump *d, + const struct btf_type *v, + __u32 id, + const void *data) +{ + enum btf_func_linkage linkage = btf_var(v)->linkage; + const struct btf_type *t; + const char *l; + __u32 type_id; + + switch (linkage) { + case BTF_FUNC_STATIC: + l = "static "; + break; + case BTF_FUNC_EXTERN: + l = "extern "; + break; + case BTF_FUNC_GLOBAL: + default: + l = ""; + break; + } + + /* format of output here is [linkage] [type] [varname] = (type)value, + * for example "static int cpu_profile_flip = (int)1" + */ + btf_dump_printf(d, "%s", l); + type_id = v->type; + t = btf__type_by_id(d->btf, type_id); + btf_dump_emit_type_cast(d, type_id, false); + btf_dump_printf(d, " %s = ", btf_name_of(d, v->name_off)); + return btf_dump_dump_type_data(d, NULL, t, type_id, data, 0, 0); +} + +static int btf_dump_array_data(struct btf_dump *d, + const struct btf_type *t, + __u32 id, + const void *data) +{ + const struct btf_array *array = btf_array(t); + const struct btf_type *elem_type; + __u32 i, elem_size = 0, elem_type_id; + bool is_array_member; + + elem_type_id = array->type; + elem_type = skip_mods_and_typedefs(d->btf, elem_type_id, NULL); + elem_size = btf__resolve_size(d->btf, elem_type_id); + if (elem_size <= 0) { + pr_warn("unexpected elem size %d for array type [%u]\n", elem_size, id); + return -EINVAL; + } + + if (btf_is_int(elem_type)) { + /* + * BTF_INT_CHAR encoding never seems to be set for + * char arrays, so if size is 1 and element is + * printable as a char, we'll do that. + */ + if (elem_size == 1) + d->typed_dump->is_array_char = true; + } + + /* note that we increment depth before calling btf_dump_print() below; + * this is intentional. btf_dump_data_newline() will not print a + * newline for depth 0 (since this leaves us with trailing newlines + * at the end of typed display), so depth is incremented first. + * For similar reasons, we decrement depth before showing the closing + * parenthesis. + */ + d->typed_dump->depth++; + btf_dump_printf(d, "[%s", btf_dump_data_newline(d)); + + /* may be a multidimensional array, so store current "is array member" + * status so we can restore it correctly later. + */ + is_array_member = d->typed_dump->is_array_member; + d->typed_dump->is_array_member = true; + for (i = 0; i < array->nelems; i++, data += elem_size) { + if (d->typed_dump->is_array_terminated) + break; + btf_dump_dump_type_data(d, NULL, elem_type, elem_type_id, data, 0, 0); + } + d->typed_dump->is_array_member = is_array_member; + d->typed_dump->depth--; + btf_dump_data_pfx(d); + btf_dump_type_values(d, "]"); + + return 0; +} + +static int btf_dump_struct_data(struct btf_dump *d, + const struct btf_type *t, + __u32 id, + const void *data) +{ + const struct btf_member *m = btf_members(t); + __u16 n = btf_vlen(t); + int i, err; + + /* note that we increment depth before calling btf_dump_print() below; + * this is intentional. btf_dump_data_newline() will not print a + * newline for depth 0 (since this leaves us with trailing newlines + * at the end of typed display), so depth is incremented first. + * For similar reasons, we decrement depth before showing the closing + * parenthesis. + */ + d->typed_dump->depth++; + btf_dump_printf(d, "{%s", btf_dump_data_newline(d)); + + for (i = 0; i < n; i++, m++) { + const struct btf_type *mtype; + const char *mname; + __u32 moffset; + __u8 bit_sz; + + mtype = btf__type_by_id(d->btf, m->type); + mname = btf_name_of(d, m->name_off); + moffset = btf_member_bit_offset(t, i); + + bit_sz = btf_member_bitfield_size(t, i); + err = btf_dump_dump_type_data(d, mname, mtype, m->type, data + moffset / 8, + moffset % 8, bit_sz); + if (err < 0) + return err; + } + d->typed_dump->depth--; + btf_dump_data_pfx(d); + btf_dump_type_values(d, "}"); + return err; +} + +static int btf_dump_ptr_data(struct btf_dump *d, + const struct btf_type *t, + __u32 id, + const void *data) +{ + btf_dump_type_values(d, "%p", *(void **)data); + return 0; +} + +static int btf_dump_get_enum_value(struct btf_dump *d, + const struct btf_type *t, + const void *data, + __u32 id, + __s64 *value) +{ + int sz = t->size; + + /* handle unaligned enum value */ + if (((uintptr_t)data) % sz) { + *value = (__s64)btf_dump_bitfield_get_data(d, t, data, 0, 0); + return 0; + } + switch (t->size) { + case 8: + *value = *(__s64 *)data; + return 0; + case 4: + *value = *(__s32 *)data; + return 0; + case 2: + *value = *(__s16 *)data; + return 0; + case 1: + *value = *(__s8 *)data; + return 0; + default: + pr_warn("unexpected size %d for enum, id:[%u]\n", t->size, id); + return -EINVAL; + } +} + +static int btf_dump_enum_data(struct btf_dump *d, + const struct btf_type *t, + __u32 id, + const void *data) +{ + const struct btf_enum *e; + __s64 value; + int i, err; + + err = btf_dump_get_enum_value(d, t, data, id, &value); + if (err) + return err; + + for (i = 0, e = btf_enum(t); i < btf_vlen(t); i++, e++) { + if (value != e->val) + continue; + btf_dump_type_values(d, "%s", btf_name_of(d, e->name_off)); + return 0; + } + + btf_dump_type_values(d, "%d", value); + return 0; +} + +static int btf_dump_datasec_data(struct btf_dump *d, + const struct btf_type *t, + __u32 id, + const void *data) +{ + const struct btf_var_secinfo *vsi; + const struct btf_type *var; + __u32 i; + int err; + + btf_dump_type_values(d, "SEC(\"%s\") ", btf_name_of(d, t->name_off)); + + for (i = 0, vsi = btf_var_secinfos(t); i < btf_vlen(t); i++, vsi++) { + var = btf__type_by_id(d->btf, vsi->type); + err = btf_dump_dump_type_data(d, NULL, var, vsi->type, data + vsi->offset, 0, 0); + if (err < 0) + return err; + btf_dump_printf(d, ";"); + } + return 0; +} + +/* return size of type, or if base type overflows, return -E2BIG. */ +static int btf_dump_type_data_check_overflow(struct btf_dump *d, + const struct btf_type *t, + __u32 id, + const void *data, + __u8 bits_offset) +{ + __s64 size = btf__resolve_size(d->btf, id); + + if (size < 0 || size >= INT_MAX) { + pr_warn("unexpected size [%lld] for id [%u]\n", + size, id); + return -EINVAL; + } + + /* Only do overflow checking for base types; we do not want to + * avoid showing part of a struct, union or array, even if we + * do not have enough data to show the full object. By + * restricting overflow checking to base types we can ensure + * that partial display succeeds, while avoiding overflowing + * and using bogus data for display. + */ + t = skip_mods_and_typedefs(d->btf, id, NULL); + if (!t) { + pr_warn("unexpected error skipping mods/typedefs for id [%u]\n", + id); + return -EINVAL; + } + + switch (btf_kind(t)) { + case BTF_KIND_INT: + case BTF_KIND_FLOAT: + case BTF_KIND_PTR: + case BTF_KIND_ENUM: + if (data + bits_offset / 8 + size > d->typed_dump->data_end) + return -E2BIG; + break; + default: + break; + } + return (int)size; +} + +static int btf_dump_type_data_check_zero(struct btf_dump *d, + const struct btf_type *t, + __u32 id, + const void *data, + __u8 bits_offset, + __u8 bit_sz) +{ + __s64 value; + int i, err; + + /* toplevel exceptions; we show zero values if + * - we ask for them (emit_zeros) + * - if we are at top-level so we see "struct empty { }" + * - or if we are an array member and the array is non-empty and + * not a char array; we don't want to be in a situation where we + * have an integer array 0, 1, 0, 1 and only show non-zero values. + * If the array contains zeroes only, or is a char array starting + * with a '\0', the array-level check_zero() will prevent showing it; + * we are concerned with determining zero value at the array member + * level here. + */ + if (d->typed_dump->emit_zeroes || d->typed_dump->depth == 0 || + (d->typed_dump->is_array_member && + !d->typed_dump->is_array_char)) + return 0; + + t = skip_mods_and_typedefs(d->btf, id, NULL); + + switch (btf_kind(t)) { + case BTF_KIND_INT: + if (bit_sz) + return btf_dump_bitfield_check_zero(d, t, data, bits_offset, bit_sz); + return btf_dump_base_type_check_zero(d, t, id, data); + case BTF_KIND_FLOAT: + case BTF_KIND_PTR: + return btf_dump_base_type_check_zero(d, t, id, data); + case BTF_KIND_ARRAY: { + const struct btf_array *array = btf_array(t); + const struct btf_type *elem_type; + __u32 elem_type_id, elem_size; + bool ischar; + + elem_type_id = array->type; + elem_size = btf__resolve_size(d->btf, elem_type_id); + elem_type = skip_mods_and_typedefs(d->btf, elem_type_id, NULL); + + ischar = btf_is_int(elem_type) && elem_size == 1; + + /* check all elements; if _any_ element is nonzero, all + * of array is displayed. We make an exception however + * for char arrays where the first element is 0; these + * are considered zeroed also, even if later elements are + * non-zero because the string is terminated. + */ + for (i = 0; i < array->nelems; i++) { + if (i == 0 && ischar && *(char *)data == 0) + return -ENODATA; + err = btf_dump_type_data_check_zero(d, elem_type, + elem_type_id, + data + + (i * elem_size), + bits_offset, 0); + if (err != -ENODATA) + return err; + } + return -ENODATA; + } + case BTF_KIND_STRUCT: + case BTF_KIND_UNION: { + const struct btf_member *m = btf_members(t); + __u16 n = btf_vlen(t); + + /* if any struct/union member is non-zero, the struct/union + * is considered non-zero and dumped. + */ + for (i = 0; i < n; i++, m++) { + const struct btf_type *mtype; + __u32 moffset; + + mtype = btf__type_by_id(d->btf, m->type); + moffset = btf_member_bit_offset(t, i); + + /* btf_int_bits() does not store member bitfield size; + * bitfield size needs to be stored here so int display + * of member can retrieve it. + */ + bit_sz = btf_member_bitfield_size(t, i); + err = btf_dump_type_data_check_zero(d, mtype, m->type, data + moffset / 8, + moffset % 8, bit_sz); + if (err != ENODATA) + return err; + } + return -ENODATA; + } + case BTF_KIND_ENUM: + if (btf_dump_get_enum_value(d, t, data, id, &value)) + return 0; + if (value == 0) + return -ENODATA; + return 0; + default: + return 0; + } +} + +/* returns size of data dumped, or error. */ +static int btf_dump_dump_type_data(struct btf_dump *d, + const char *fname, + const struct btf_type *t, + __u32 id, + const void *data, + __u8 bits_offset, + __u8 bit_sz) +{ + int size, err; + + size = btf_dump_type_data_check_overflow(d, t, id, data, bits_offset); + if (size < 0) + return size; + err = btf_dump_type_data_check_zero(d, t, id, data, bits_offset, bit_sz); + if (err) { + /* zeroed data is expected and not an error, so simply skip + * dumping such data. Record other errors however. + */ + if (err == -ENODATA) + return size; + return err; + } + btf_dump_data_pfx(d); + + if (!d->typed_dump->skip_names) { + if (fname && strlen(fname) > 0) + btf_dump_printf(d, ".%s = ", fname); + btf_dump_emit_type_cast(d, id, true); + } + + t = skip_mods_and_typedefs(d->btf, id, NULL); + + switch (btf_kind(t)) { + case BTF_KIND_UNKN: + case BTF_KIND_FWD: + case BTF_KIND_FUNC: + case BTF_KIND_FUNC_PROTO: + err = btf_dump_unsupported_data(d, t, id); + break; + case BTF_KIND_INT: + if (bit_sz) + err = btf_dump_bitfield_data(d, t, data, bits_offset, bit_sz); + else + err = btf_dump_int_data(d, t, id, data, bits_offset); + break; + case BTF_KIND_FLOAT: + err = btf_dump_float_data(d, t, id, data); + break; + case BTF_KIND_PTR: + err = btf_dump_ptr_data(d, t, id, data); + break; + case BTF_KIND_ARRAY: + err = btf_dump_array_data(d, t, id, data); + break; + case BTF_KIND_STRUCT: + case BTF_KIND_UNION: + err = btf_dump_struct_data(d, t, id, data); + break; + case BTF_KIND_ENUM: + /* handle bitfield and int enum values */ + if (bit_sz) { + unsigned __int128 print_num; + __s64 enum_val; + + print_num = btf_dump_bitfield_get_data(d, t, data, bits_offset, bit_sz); + enum_val = (__s64)print_num; + err = btf_dump_enum_data(d, t, id, &enum_val); + } else + err = btf_dump_enum_data(d, t, id, data); + break; + case BTF_KIND_VAR: + err = btf_dump_var_data(d, t, id, data); + break; + case BTF_KIND_DATASEC: + err = btf_dump_datasec_data(d, t, id, data); + break; + default: + pr_warn("unexpected kind [%u] for id [%u]\n", + BTF_INFO_KIND(t->info), id); + return -EINVAL; + } + if (err < 0) + return err; + return size; +} + +int btf_dump__dump_type_data(struct btf_dump *d, __u32 id, + const void *data, size_t data_sz, + const struct btf_dump_type_data_opts *opts) +{ + const struct btf_type *t; + int ret; + + if (!OPTS_VALID(opts, btf_dump_type_data_opts)) + return libbpf_err(-EINVAL); + + t = btf__type_by_id(d->btf, id); + if (!t) + return libbpf_err(-ENOENT); + + d->typed_dump = calloc(1, sizeof(struct btf_dump_data)); + if (!d->typed_dump) + return libbpf_err(-ENOMEM); + + d->typed_dump->data_end = data + data_sz; + d->typed_dump->indent_lvl = OPTS_GET(opts, indent_level, 0); + /* default indent string is a tab */ + if (!opts->indent_str) + d->typed_dump->indent_str[0] = '\t'; + else + strncat(d->typed_dump->indent_str, opts->indent_str, + sizeof(d->typed_dump->indent_str) - 1); + + d->typed_dump->compact = OPTS_GET(opts, compact, false); + d->typed_dump->skip_names = OPTS_GET(opts, skip_names, false); + d->typed_dump->emit_zeroes = OPTS_GET(opts, emit_zeroes, false); + + ret = btf_dump_dump_type_data(d, NULL, t, id, data, 0, 0); + + free(d->typed_dump); + + return libbpf_err(ret); +} diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index 944c99d1ded3..5bfc10722647 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -373,5 +373,6 @@ LIBBPF_0.5.0 { bpf_map__initial_value; bpf_map_lookup_and_delete_elem_flags; bpf_object__gen_loader; + btf_dump__dump_type_data; libbpf_set_strict_mode; } LIBBPF_0.4.0; diff --git a/tools/testing/selftests/bpf/prog_tests/btf_dump.c b/tools/testing/selftests/bpf/prog_tests/btf_dump.c index 1b90e684ff13..0b4ba53b5961 100644 --- a/tools/testing/selftests/bpf/prog_tests/btf_dump.c +++ b/tools/testing/selftests/bpf/prog_tests/btf_dump.c @@ -232,7 +232,576 @@ err_out: btf__free(btf); } +#define STRSIZE 4096 + +static void btf_dump_snprintf(void *ctx, const char *fmt, va_list args) +{ + char *s = ctx, new[STRSIZE]; + + vsnprintf(new, STRSIZE, fmt, args); + if (strlen(s) < STRSIZE) + strncat(s, new, STRSIZE - strlen(s) - 1); +} + +static int btf_dump_data(struct btf *btf, struct btf_dump *d, + char *name, char *prefix, __u64 flags, void *ptr, + size_t ptr_sz, char *str, const char *expected_val) +{ + DECLARE_LIBBPF_OPTS(btf_dump_type_data_opts, opts); + size_t type_sz; + __s32 type_id; + int ret = 0; + + if (flags & BTF_F_COMPACT) + opts.compact = true; + if (flags & BTF_F_NONAME) + opts.skip_names = true; + if (flags & BTF_F_ZERO) + opts.emit_zeroes = true; + if (prefix) { + ASSERT_STRNEQ(name, prefix, strlen(prefix), + "verify prefix match"); + name += strlen(prefix) + 1; + } + type_id = btf__find_by_name(btf, name); + if (!ASSERT_GE(type_id, 0, "find type id")) + return -ENOENT; + type_sz = btf__resolve_size(btf, type_id); + str[0] = '\0'; + ret = btf_dump__dump_type_data(d, type_id, ptr, ptr_sz, &opts); + if (type_sz <= ptr_sz) { + if (!ASSERT_EQ(ret, type_sz, "failed/unexpected type_sz")) + return -EINVAL; + } else { + if (!ASSERT_EQ(ret, -E2BIG, "failed to return -E2BIG")) + return -EINVAL; + } + if (!ASSERT_STREQ(str, expected_val, "ensure expected/actual match")) + return -EFAULT; + return 0; +} + +#define TEST_BTF_DUMP_DATA(_b, _d, _prefix, _str, _type, _flags, \ + _expected, ...) \ + do { \ + char __ptrtype[64] = #_type; \ + char *_ptrtype = (char *)__ptrtype; \ + _type _ptrdata = __VA_ARGS__; \ + void *_ptr = &_ptrdata; \ + \ + (void) btf_dump_data(_b, _d, _ptrtype, _prefix, _flags, \ + _ptr, sizeof(_type), _str, \ + _expected); \ + } while (0) + +/* Use where expected data string matches its stringified declaration */ +#define TEST_BTF_DUMP_DATA_C(_b, _d, _prefix, _str, _type, _flags, \ + ...) \ + TEST_BTF_DUMP_DATA(_b, _d, _prefix, _str, _type, _flags, \ + "(" #_type ")" #__VA_ARGS__, __VA_ARGS__) + +/* overflow test; pass typesize < expected type size, ensure E2BIG returned */ +#define TEST_BTF_DUMP_DATA_OVER(_b, _d, _prefix, _str, _type, _type_sz, \ + _expected, ...) \ + do { \ + char __ptrtype[64] = #_type; \ + char *_ptrtype = (char *)__ptrtype; \ + _type _ptrdata = __VA_ARGS__; \ + void *_ptr = &_ptrdata; \ + \ + (void) btf_dump_data(_b, _d, _ptrtype, _prefix, 0, \ + _ptr, _type_sz, _str, _expected); \ + } while (0) + +#define TEST_BTF_DUMP_VAR(_b, _d, _prefix, _str, _var, _type, _flags, \ + _expected, ...) \ + do { \ + _type _ptrdata = __VA_ARGS__; \ + void *_ptr = &_ptrdata; \ + \ + (void) btf_dump_data(_b, _d, _var, _prefix, _flags, \ + _ptr, sizeof(_type), _str, \ + _expected); \ + } while (0) + +static void test_btf_dump_int_data(struct btf *btf, struct btf_dump *d, + char *str) +{ + /* simple int */ + TEST_BTF_DUMP_DATA_C(btf, d, NULL, str, int, BTF_F_COMPACT, 1234); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, int, BTF_F_COMPACT | BTF_F_NONAME, + "1234", 1234); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, int, 0, "(int)1234", 1234); + + /* zero value should be printed at toplevel */ + TEST_BTF_DUMP_DATA(btf, d, NULL, str, int, BTF_F_COMPACT, "(int)0", 0); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, int, BTF_F_COMPACT | BTF_F_NONAME, + "0", 0); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, int, BTF_F_COMPACT | BTF_F_ZERO, + "(int)0", 0); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, int, + BTF_F_COMPACT | BTF_F_NONAME | BTF_F_ZERO, + "0", 0); + TEST_BTF_DUMP_DATA_C(btf, d, NULL, str, int, BTF_F_COMPACT, -4567); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, int, BTF_F_COMPACT | BTF_F_NONAME, + "-4567", -4567); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, int, 0, "(int)-4567", -4567); + + TEST_BTF_DUMP_DATA_OVER(btf, d, NULL, str, int, sizeof(int)-1, "", 1); +} + +static void test_btf_dump_float_data(struct btf *btf, struct btf_dump *d, + char *str) +{ + float t1 = 1.234567; + float t2 = -1.234567; + float t3 = 0.0; + double t4 = 5.678912; + double t5 = -5.678912; + double t6 = 0.0; + long double t7 = 9.876543; + long double t8 = -9.876543; + long double t9 = 0.0; + + /* since the kernel does not likely have any float types in its BTF, we + * will need to add some of various sizes. + */ + + ASSERT_GT(btf__add_float(btf, "test_float", 4), 0, "add float"); + ASSERT_OK(btf_dump_data(btf, d, "test_float", NULL, 0, &t1, 4, str, + "(test_float)1.234567"), "dump float"); + ASSERT_OK(btf_dump_data(btf, d, "test_float", NULL, 0, &t2, 4, str, + "(test_float)-1.234567"), "dump float"); + ASSERT_OK(btf_dump_data(btf, d, "test_float", NULL, 0, &t3, 4, str, + "(test_float)0.000000"), "dump float"); + + ASSERT_GT(btf__add_float(btf, "test_double", 8), 0, "add_double"); + ASSERT_OK(btf_dump_data(btf, d, "test_double", NULL, 0, &t4, 8, str, + "(test_double)5.678912"), "dump double"); + ASSERT_OK(btf_dump_data(btf, d, "test_double", NULL, 0, &t5, 8, str, + "(test_double)-5.678912"), "dump double"); + ASSERT_OK(btf_dump_data(btf, d, "test_double", NULL, 0, &t6, 8, str, + "(test_double)0.000000"), "dump double"); + + ASSERT_GT(btf__add_float(btf, "test_long_double", 16), 0, "add long double"); + ASSERT_OK(btf_dump_data(btf, d, "test_long_double", NULL, 0, &t7, 16, + str, "(test_long_double)9.876543"), + "dump long_double"); + ASSERT_OK(btf_dump_data(btf, d, "test_long_double", NULL, 0, &t8, 16, + str, "(test_long_double)-9.876543"), + "dump long_double"); + ASSERT_OK(btf_dump_data(btf, d, "test_long_double", NULL, 0, &t9, 16, + str, "(test_long_double)0.000000"), + "dump long_double"); +} + +static void test_btf_dump_char_data(struct btf *btf, struct btf_dump *d, + char *str) +{ + /* simple char */ + TEST_BTF_DUMP_DATA_C(btf, d, NULL, str, char, BTF_F_COMPACT, 100); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, char, BTF_F_COMPACT | BTF_F_NONAME, + "100", 100); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, char, 0, "(char)100", 100); + /* zero value should be printed at toplevel */ + TEST_BTF_DUMP_DATA(btf, d, NULL, str, char, BTF_F_COMPACT, + "(char)0", 0); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, char, BTF_F_COMPACT | BTF_F_NONAME, + "0", 0); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, char, BTF_F_COMPACT | BTF_F_ZERO, + "(char)0", 0); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, char, BTF_F_COMPACT | BTF_F_NONAME | BTF_F_ZERO, + "0", 0); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, char, 0, "(char)0", 0); + + TEST_BTF_DUMP_DATA_OVER(btf, d, NULL, str, char, sizeof(char)-1, "", 100); +} + +static void test_btf_dump_typedef_data(struct btf *btf, struct btf_dump *d, + char *str) +{ + /* simple typedef */ + TEST_BTF_DUMP_DATA_C(btf, d, NULL, str, uint64_t, BTF_F_COMPACT, 100); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, u64, BTF_F_COMPACT | BTF_F_NONAME, + "1", 1); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, u64, 0, "(u64)1", 1); + /* zero value should be printed at toplevel */ + TEST_BTF_DUMP_DATA(btf, d, NULL, str, u64, BTF_F_COMPACT, "(u64)0", 0); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, u64, BTF_F_COMPACT | BTF_F_NONAME, + "0", 0); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, u64, BTF_F_COMPACT | BTF_F_ZERO, + "(u64)0", 0); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, u64, + BTF_F_COMPACT | BTF_F_NONAME | BTF_F_ZERO, + "0", 0); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, u64, 0, "(u64)0", 0); + + /* typedef struct */ + TEST_BTF_DUMP_DATA_C(btf, d, NULL, str, atomic_t, BTF_F_COMPACT, + {.counter = (int)1,}); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, atomic_t, BTF_F_COMPACT | BTF_F_NONAME, + "{1,}", { .counter = 1 }); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, atomic_t, 0, +"(atomic_t){\n" +" .counter = (int)1,\n" +"}", + {.counter = 1,}); + /* typedef with 0 value should be printed at toplevel */ + TEST_BTF_DUMP_DATA(btf, d, NULL, str, atomic_t, BTF_F_COMPACT, "(atomic_t){}", + {.counter = 0,}); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, atomic_t, BTF_F_COMPACT | BTF_F_NONAME, + "{}", {.counter = 0,}); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, atomic_t, 0, +"(atomic_t){\n" +"}", + {.counter = 0,}); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, atomic_t, BTF_F_COMPACT | BTF_F_ZERO, + "(atomic_t){.counter = (int)0,}", + {.counter = 0,}); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, atomic_t, + BTF_F_COMPACT | BTF_F_NONAME | BTF_F_ZERO, + "{0,}", {.counter = 0,}); + TEST_BTF_DUMP_DATA(btf, d, NULL, str, atomic_t, BTF_F_ZERO, +"(atomic_t){\n" +" .counter = (int)0,\n" +"}", + { .counter = 0,}); + + /* overflow should show type but not value since it overflows */ + TEST_BTF_DUMP_DATA_OVER(btf, d, NULL, str, atomic_t, sizeof(atomic_t)-1, + "(atomic_t){\n", { .counter = 1}); +} + +static void test_btf_dump_enum_data(struct btf *btf, struct btf_dump *d, + char *str) +{ + /* enum where enum value does (and does not) exist */ + TEST_BTF_DUMP_DATA_C(btf, d, "enum", str, enum bpf_cmd, BTF_F_COMPACT, + BPF_MAP_CREATE); + TEST_BTF_DUMP_DATA(btf, d, "enum", str, enum bpf_cmd, BTF_F_COMPACT, + "(enum bpf_cmd)BPF_MAP_CREATE", 0); + TEST_BTF_DUMP_DATA(btf, d, "enum", str, enum bpf_cmd, + BTF_F_COMPACT | BTF_F_NONAME, + "BPF_MAP_CREATE", + BPF_MAP_CREATE); + TEST_BTF_DUMP_DATA(btf, d, "enum", str, enum bpf_cmd, 0, + "(enum bpf_cmd)BPF_MAP_CREATE", + BPF_MAP_CREATE); + TEST_BTF_DUMP_DATA(btf, d, "enum", str, enum bpf_cmd, + BTF_F_COMPACT | BTF_F_NONAME | BTF_F_ZERO, + "BPF_MAP_CREATE", 0); + TEST_BTF_DUMP_DATA(btf, d, "enum", str, enum bpf_cmd, + BTF_F_COMPACT | BTF_F_ZERO, + "(enum bpf_cmd)BPF_MAP_CREATE", + BPF_MAP_CREATE); + TEST_BTF_DUMP_DATA(btf, d, "enum", str, enum bpf_cmd, + BTF_F_COMPACT | BTF_F_NONAME | BTF_F_ZERO, + "BPF_MAP_CREATE", BPF_MAP_CREATE); + TEST_BTF_DUMP_DATA_C(btf, d, "enum", str, enum bpf_cmd, BTF_F_COMPACT, 2000); + TEST_BTF_DUMP_DATA(btf, d, "enum", str, enum bpf_cmd, + BTF_F_COMPACT | BTF_F_NONAME, + "2000", 2000); + TEST_BTF_DUMP_DATA(btf, d, "enum", str, enum bpf_cmd, 0, + "(enum bpf_cmd)2000", 2000); + + TEST_BTF_DUMP_DATA_OVER(btf, d, "enum", str, enum bpf_cmd, + sizeof(enum bpf_cmd) - 1, "", BPF_MAP_CREATE); +} + +static void test_btf_dump_struct_data(struct btf *btf, struct btf_dump *d, + char *str) +{ + DECLARE_LIBBPF_OPTS(btf_dump_type_data_opts, opts); + char zero_data[512] = { }; + char type_data[512]; + void *fops = type_data; + void *skb = type_data; + size_t type_sz; + __s32 type_id; + char *cmpstr; + int ret; + + memset(type_data, 255, sizeof(type_data)); + + /* simple struct */ + TEST_BTF_DUMP_DATA_C(btf, d, "struct", str, struct btf_enum, BTF_F_COMPACT, + {.name_off = (__u32)3,.val = (__s32)-1,}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct btf_enum, + BTF_F_COMPACT | BTF_F_NONAME, + "{3,-1,}", + { .name_off = 3, .val = -1,}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct btf_enum, 0, +"(struct btf_enum){\n" +" .name_off = (__u32)3,\n" +" .val = (__s32)-1,\n" +"}", + { .name_off = 3, .val = -1,}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct btf_enum, + BTF_F_COMPACT | BTF_F_NONAME, + "{-1,}", + { .name_off = 0, .val = -1,}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct btf_enum, + BTF_F_COMPACT | BTF_F_NONAME | BTF_F_ZERO, + "{0,-1,}", + { .name_off = 0, .val = -1,}); + /* empty struct should be printed */ + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct btf_enum, BTF_F_COMPACT, + "(struct btf_enum){}", + { .name_off = 0, .val = 0,}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct btf_enum, + BTF_F_COMPACT | BTF_F_NONAME, + "{}", + { .name_off = 0, .val = 0,}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct btf_enum, 0, +"(struct btf_enum){\n" +"}", + { .name_off = 0, .val = 0,}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct btf_enum, + BTF_F_COMPACT | BTF_F_ZERO, + "(struct btf_enum){.name_off = (__u32)0,.val = (__s32)0,}", + { .name_off = 0, .val = 0,}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct btf_enum, + BTF_F_ZERO, +"(struct btf_enum){\n" +" .name_off = (__u32)0,\n" +" .val = (__s32)0,\n" +"}", + { .name_off = 0, .val = 0,}); + + /* struct with pointers */ + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct list_head, BTF_F_COMPACT, + "(struct list_head){.next = (struct list_head *)0x1,}", + { .next = (struct list_head *)1 }); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct list_head, 0, +"(struct list_head){\n" +" .next = (struct list_head *)0x1,\n" +"}", + { .next = (struct list_head *)1 }); + /* NULL pointer should not be displayed */ + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct list_head, BTF_F_COMPACT, + "(struct list_head){}", + { .next = (struct list_head *)0 }); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct list_head, 0, +"(struct list_head){\n" +"}", + { .next = (struct list_head *)0 }); + + /* struct with function pointers */ + type_id = btf__find_by_name(btf, "file_operations"); + if (ASSERT_GT(type_id, 0, "find type id")) { + type_sz = btf__resolve_size(btf, type_id); + str[0] = '\0'; + + ret = btf_dump__dump_type_data(d, type_id, fops, type_sz, &opts); + ASSERT_EQ(ret, type_sz, + "unexpected return value dumping file_operations"); + cmpstr = +"(struct file_operations){\n" +" .owner = (struct module *)0xffffffffffffffff,\n" +" .llseek = (loff_t (*)(struct file *, loff_t, int))0xffffffffffffffff,"; + + ASSERT_STRNEQ(str, cmpstr, strlen(cmpstr), "file_operations"); + } + + /* struct with char array */ + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct bpf_prog_info, BTF_F_COMPACT, + "(struct bpf_prog_info){.name = (char[16])['f','o','o',],}", + { .name = "foo",}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct bpf_prog_info, + BTF_F_COMPACT | BTF_F_NONAME, + "{['f','o','o',],}", + {.name = "foo",}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct bpf_prog_info, 0, +"(struct bpf_prog_info){\n" +" .name = (char[16])[\n" +" 'f',\n" +" 'o',\n" +" 'o',\n" +" ],\n" +"}", + {.name = "foo",}); + /* leading null char means do not display string */ + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct bpf_prog_info, BTF_F_COMPACT, + "(struct bpf_prog_info){}", + {.name = {'\0', 'f', 'o', 'o'}}); + /* handle non-printable characters */ + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct bpf_prog_info, BTF_F_COMPACT, + "(struct bpf_prog_info){.name = (char[16])[1,2,3,],}", + { .name = {1, 2, 3, 0}}); + + /* struct with non-char array */ + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct __sk_buff, BTF_F_COMPACT, + "(struct __sk_buff){.cb = (__u32[5])[1,2,3,4,5,],}", + { .cb = {1, 2, 3, 4, 5,},}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct __sk_buff, + BTF_F_COMPACT | BTF_F_NONAME, + "{[1,2,3,4,5,],}", + { .cb = { 1, 2, 3, 4, 5},}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct __sk_buff, 0, +"(struct __sk_buff){\n" +" .cb = (__u32[5])[\n" +" 1,\n" +" 2,\n" +" 3,\n" +" 4,\n" +" 5,\n" +" ],\n" +"}", + { .cb = { 1, 2, 3, 4, 5},}); + /* For non-char, arrays, show non-zero values only */ + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct __sk_buff, BTF_F_COMPACT, + "(struct __sk_buff){.cb = (__u32[5])[0,0,1,0,0,],}", + { .cb = { 0, 0, 1, 0, 0},}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct __sk_buff, 0, +"(struct __sk_buff){\n" +" .cb = (__u32[5])[\n" +" 0,\n" +" 0,\n" +" 1,\n" +" 0,\n" +" 0,\n" +" ],\n" +"}", + { .cb = { 0, 0, 1, 0, 0},}); + + /* struct with bitfields */ + TEST_BTF_DUMP_DATA_C(btf, d, "struct", str, struct bpf_insn, BTF_F_COMPACT, + {.code = (__u8)1,.dst_reg = (__u8)0x2,.src_reg = (__u8)0x3,.off = (__s16)4,.imm = (__s32)5,}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct bpf_insn, + BTF_F_COMPACT | BTF_F_NONAME, + "{1,0x2,0x3,4,5,}", + { .code = 1, .dst_reg = 0x2, .src_reg = 0x3, .off = 4, + .imm = 5,}); + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct bpf_insn, 0, +"(struct bpf_insn){\n" +" .code = (__u8)1,\n" +" .dst_reg = (__u8)0x2,\n" +" .src_reg = (__u8)0x3,\n" +" .off = (__s16)4,\n" +" .imm = (__s32)5,\n" +"}", + {.code = 1, .dst_reg = 2, .src_reg = 3, .off = 4, .imm = 5}); + + /* zeroed bitfields should not be displayed */ + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct bpf_insn, BTF_F_COMPACT, + "(struct bpf_insn){.dst_reg = (__u8)0x1,}", + { .code = 0, .dst_reg = 1}); + + /* struct with enum bitfield */ + type_id = btf__find_by_name(btf, "fs_context"); + if (ASSERT_GT(type_id, 0, "find fs_context")) { + type_sz = btf__resolve_size(btf, type_id); + str[0] = '\0'; + + opts.emit_zeroes = true; + ret = btf_dump__dump_type_data(d, type_id, zero_data, type_sz, &opts); + ASSERT_EQ(ret, type_sz, + "unexpected return value dumping fs_context"); + + ASSERT_NEQ(strstr(str, "FS_CONTEXT_FOR_MOUNT"), NULL, + "bitfield value not present"); + } + + /* struct with nested anon union */ + TEST_BTF_DUMP_DATA(btf, d, "struct", str, struct bpf_sock_ops, BTF_F_COMPACT, + "(struct bpf_sock_ops){.op = (__u32)1,(union){.args = (__u32[4])[1,2,3,4,],.reply = (__u32)1,.replylong = (__u32[4])[1,2,3,4,],},}", + { .op = 1, .args = { 1, 2, 3, 4}}); + + /* union with nested struct */ + TEST_BTF_DUMP_DATA(btf, d, "union", str, union bpf_iter_link_info, BTF_F_COMPACT, + "(union bpf_iter_link_info){.map = (struct){.map_fd = (__u32)1,},}", + { .map = { .map_fd = 1 }}); + + /* struct skb with nested structs/unions; because type output is so + * complex, we don't do a string comparison, just verify we return + * the type size as the amount of data displayed. + */ + type_id = btf__find_by_name(btf, "sk_buff"); + if (ASSERT_GT(type_id, 0, "find struct sk_buff")) { + type_sz = btf__resolve_size(btf, type_id); + str[0] = '\0'; + + ret = btf_dump__dump_type_data(d, type_id, skb, type_sz, &opts); + ASSERT_EQ(ret, type_sz, + "unexpected return value dumping sk_buff"); + } + + /* overflow bpf_sock_ops struct with final element nonzero/zero. + * Regardless of the value of the final field, we don't have all the + * data we need to display it, so we should trigger an overflow. + * In other words oveflow checking should trump "is field zero?" + * checks because if we've overflowed, it shouldn't matter what the + * field is - we can't trust its value so shouldn't display it. + */ + TEST_BTF_DUMP_DATA_OVER(btf, d, "struct", str, struct bpf_sock_ops, + sizeof(struct bpf_sock_ops) - 1, + "(struct bpf_sock_ops){\n\t.op = (__u32)1,\n", + { .op = 1, .skb_tcp_flags = 2}); + TEST_BTF_DUMP_DATA_OVER(btf, d, "struct", str, struct bpf_sock_ops, + sizeof(struct bpf_sock_ops) - 1, + "(struct bpf_sock_ops){\n\t.op = (__u32)1,\n", + { .op = 1, .skb_tcp_flags = 0}); +} + +static void test_btf_dump_var_data(struct btf *btf, struct btf_dump *d, + char *str) +{ + TEST_BTF_DUMP_VAR(btf, d, NULL, str, "cpu_number", int, BTF_F_COMPACT, + "int cpu_number = (int)100", 100); + TEST_BTF_DUMP_VAR(btf, d, NULL, str, "cpu_profile_flip", int, BTF_F_COMPACT, + "static int cpu_profile_flip = (int)2", 2); +} + +static void test_btf_datasec(struct btf *btf, struct btf_dump *d, char *str, + const char *name, const char *expected_val, + void *data, size_t data_sz) +{ + DECLARE_LIBBPF_OPTS(btf_dump_type_data_opts, opts); + int ret = 0, cmp; + size_t secsize; + __s32 type_id; + + opts.compact = true; + + type_id = btf__find_by_name(btf, name); + if (!ASSERT_GT(type_id, 0, "find type id")) + return; + + secsize = btf__resolve_size(btf, type_id); + ASSERT_EQ(secsize, 0, "verify section size"); + + str[0] = '\0'; + ret = btf_dump__dump_type_data(d, type_id, data, data_sz, &opts); + ASSERT_EQ(ret, 0, "unexpected return value"); + + cmp = strcmp(str, expected_val); + ASSERT_EQ(cmp, 0, "ensure expected/actual match"); +} + +static void test_btf_dump_datasec_data(char *str) +{ + struct btf *btf = btf__parse("xdping_kern.o", NULL); + struct btf_dump_opts opts = { .ctx = str }; + char license[4] = "GPL"; + struct btf_dump *d; + + if (!ASSERT_OK_PTR(btf, "xdping_kern.o BTF not found")) + return; + + d = btf_dump__new(btf, NULL, &opts, btf_dump_snprintf); + if (!ASSERT_OK_PTR(d, "could not create BTF dump")) + return; + + test_btf_datasec(btf, d, str, "license", + "SEC(\"license\") char[4] _license = (char[4])['G','P','L',];", + license, sizeof(license)); +} + void test_btf_dump() { + char str[STRSIZE]; + struct btf_dump_opts opts = { .ctx = str }; + struct btf_dump *d; + struct btf *btf; int i; for (i = 0; i < ARRAY_SIZE(btf_dump_test_cases); i++) { @@ -245,4 +814,33 @@ void test_btf_dump() { } if (test__start_subtest("btf_dump: incremental")) test_btf_dump_incremental(); + + btf = libbpf_find_kernel_btf(); + if (!ASSERT_OK_PTR(btf, "no kernel BTF found")) + return; + + d = btf_dump__new(btf, NULL, &opts, btf_dump_snprintf); + if (!ASSERT_OK_PTR(d, "could not create BTF dump")) + return; + + /* Verify type display for various types. */ + if (test__start_subtest("btf_dump: int_data")) + test_btf_dump_int_data(btf, d, str); + if (test__start_subtest("btf_dump: float_data")) + test_btf_dump_float_data(btf, d, str); + if (test__start_subtest("btf_dump: char_data")) + test_btf_dump_char_data(btf, d, str); + if (test__start_subtest("btf_dump: typedef_data")) + test_btf_dump_typedef_data(btf, d, str); + if (test__start_subtest("btf_dump: enum_data")) + test_btf_dump_enum_data(btf, d, str); + if (test__start_subtest("btf_dump: struct_data")) + test_btf_dump_struct_data(btf, d, str); + if (test__start_subtest("btf_dump: var_data")) + test_btf_dump_var_data(btf, d, str); + btf_dump__free(d); + btf__free(btf); + + if (test__start_subtest("btf_dump: datasec_data")) + test_btf_dump_datasec_data(str); } diff --git a/tools/testing/selftests/bpf/test_progs.h b/tools/testing/selftests/bpf/test_progs.h index 8ef7f334e715..c8c2bf878f67 100644 --- a/tools/testing/selftests/bpf/test_progs.h +++ b/tools/testing/selftests/bpf/test_progs.h @@ -221,6 +221,18 @@ extern int test__join_cgroup(const char *path); ___ok; \ }) +#define ASSERT_STRNEQ(actual, expected, len, name) ({ \ + static int duration = 0; \ + const char *___act = actual; \ + const char *___exp = expected; \ + int ___len = len; \ + bool ___ok = strncmp(___act, ___exp, ___len) == 0; \ + CHECK(!___ok, (name), \ + "unexpected %s: actual '%.*s' != expected '%.*s'\n", \ + (name), ___len, ___act, ___len, ___exp); \ + ___ok; \ +}) + #define ASSERT_OK(res, name) ({ \ static int duration = 0; \ long long ___res = (res); \ |