diff options
author | Alexei Starovoitov <ast@kernel.org> | 2019-08-07 14:43:50 -0700 |
---|---|---|
committer | Alexei Starovoitov <ast@kernel.org> | 2019-08-07 14:43:50 -0700 |
commit | 726e333fd2e95a14182fcfc1a4fe17725727a115 (patch) | |
tree | d8e0e5c5cd477ddf1ca0af0717623f1f19488972 /tools | |
parent | 682cdbdc216028f5340e48e92e59e3e9503957bb (diff) | |
parent | 29e1c66872450adba0ad552ff6019932168676f3 (diff) | |
download | linux-726e333fd2e95a14182fcfc1a4fe17725727a115.tar.bz2 |
Merge branch 'compile-once-run-everywhere'
Andrii Nakryiko says:
====================
This patch set implements central part of CO-RE (Compile Once - Run
Everywhere, see [0] and [1] for slides and video): relocating fields offsets.
Most of the details are written down as comments to corresponding parts of the
code.
Patch #1 adds a bunch of commonly useful btf_xxx helpers to simplify working
with BTF types.
Patch #2 converts existing libbpf code to these new helpers and removes some
of pre-existing ones.
Patch #3 adds loading of .BTF.ext offset relocations section and macros to
work with its contents.
Patch #4 implements CO-RE relocations algorithm in libbpf.
Patch #5 introduced BPF_CORE_READ macro, hiding usage of Clang's
__builtin_preserve_access_index intrinsic that records offset relocation.
Patches #6-#14 adds selftests validating various parts of relocation handling,
type compatibility, etc.
For all tests to work, you'll need latest Clang/LLVM supporting
__builtin_preserve_access_index intrinsic, used for recording offset
relocations. Kernel on which selftests run should have BTF information built
in (CONFIG_DEBUG_INFO_BTF=y).
[0] http://vger.kernel.org/bpfconf2019.html#session-2
[1] http://vger.kernel.org/lpc-bpf2018.html#session-2
v5->v6:
- fix bad comment formatting for real (Alexei);
v4->v5:
- drop constness for btf_xxx() helpers, allowing to avoid type casts (Alexei);
- rebase on latest bpf-next, change test__printf back to printf;
v3->v4:
- added btf_xxx helpers (Alexei);
- switched libbpf code to new helpers;
- reduced amount of logging and simplified format in few places (Alexei);
- made flavor name parsing logic more strict (exactly three underscores);
- no uname() error checking (Alexei);
- updated misc tests to reflect latest Clang fixes (Yonghong);
v2->v3:
- enclose BPF_CORE_READ args in parens (Song);
v1->v2:
- add offsetofend(), fix btf_ext optional fields checks (Song);
- add bpf_core_dump_spec() for logging spec representation;
- move special first element processing out of the loop (Song);
- typo fixes (Song);
- drop BPF_ST | BPF_MEM insn relocation (Alexei);
- extracted BPF_CORE_READ into bpf_helpers (Alexei);
- added extra tests validating Clang capturing relocs correctly (Yonghong);
- switch core_relocs.c to use sub-tests;
- updated mods tests after Clang bug was fixed (Yonghong);
- fix bug enumerating candidate types;
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'tools')
62 files changed, 2981 insertions, 281 deletions
diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c index 467224feb43b..aacb7608f02d 100644 --- a/tools/lib/bpf/btf.c +++ b/tools/lib/bpf/btf.c @@ -19,13 +19,6 @@ #define BTF_MAX_NR_TYPES 0x7fffffff #define BTF_MAX_STR_OFFSET 0x7fffffff -#define IS_MODIFIER(k) (((k) == BTF_KIND_TYPEDEF) || \ - ((k) == BTF_KIND_VOLATILE) || \ - ((k) == BTF_KIND_CONST) || \ - ((k) == BTF_KIND_RESTRICT)) - -#define IS_VAR(k) ((k) == BTF_KIND_VAR) - static struct btf_type btf_void; struct btf { @@ -42,47 +35,6 @@ struct btf { int fd; }; -struct btf_ext_info { - /* - * info points to the individual info section (e.g. func_info and - * line_info) from the .BTF.ext. It does not include the __u32 rec_size. - */ - void *info; - __u32 rec_size; - __u32 len; -}; - -struct btf_ext { - union { - struct btf_ext_header *hdr; - void *data; - }; - struct btf_ext_info func_info; - struct btf_ext_info line_info; - __u32 data_size; -}; - -struct btf_ext_info_sec { - __u32 sec_name_off; - __u32 num_info; - /* Followed by num_info * record_size number of bytes */ - __u8 data[0]; -}; - -/* The minimum bpf_func_info checked by the loader */ -struct bpf_func_info_min { - __u32 insn_off; - __u32 type_id; -}; - -/* The minimum bpf_line_info checked by the loader */ -struct bpf_line_info_min { - __u32 insn_off; - __u32 file_name_off; - __u32 line_off; - __u32 line_col; -}; - static inline __u64 ptr_to_u64(const void *ptr) { return (__u64) (unsigned long) ptr; @@ -192,9 +144,9 @@ static int btf_parse_str_sec(struct btf *btf) static int btf_type_size(struct btf_type *t) { int base_size = sizeof(struct btf_type); - __u16 vlen = BTF_INFO_VLEN(t->info); + __u16 vlen = btf_vlen(t); - switch (BTF_INFO_KIND(t->info)) { + switch (btf_kind(t)) { case BTF_KIND_FWD: case BTF_KIND_CONST: case BTF_KIND_VOLATILE: @@ -219,7 +171,7 @@ static int btf_type_size(struct btf_type *t) case BTF_KIND_DATASEC: return base_size + vlen * sizeof(struct btf_var_secinfo); default: - pr_debug("Unsupported BTF_KIND:%u\n", BTF_INFO_KIND(t->info)); + pr_debug("Unsupported BTF_KIND:%u\n", btf_kind(t)); return -EINVAL; } } @@ -263,7 +215,7 @@ const struct btf_type *btf__type_by_id(const struct btf *btf, __u32 type_id) static bool btf_type_is_void(const struct btf_type *t) { - return t == &btf_void || BTF_INFO_KIND(t->info) == BTF_KIND_FWD; + return t == &btf_void || btf_is_fwd(t); } static bool btf_type_is_void_or_null(const struct btf_type *t) @@ -284,7 +236,7 @@ __s64 btf__resolve_size(const struct btf *btf, __u32 type_id) t = btf__type_by_id(btf, type_id); for (i = 0; i < MAX_RESOLVE_DEPTH && !btf_type_is_void_or_null(t); i++) { - switch (BTF_INFO_KIND(t->info)) { + switch (btf_kind(t)) { case BTF_KIND_INT: case BTF_KIND_STRUCT: case BTF_KIND_UNION: @@ -303,7 +255,7 @@ __s64 btf__resolve_size(const struct btf *btf, __u32 type_id) type_id = t->type; break; case BTF_KIND_ARRAY: - array = (const struct btf_array *)(t + 1); + array = btf_array(t); if (nelems && array->nelems > UINT32_MAX / nelems) return -E2BIG; nelems *= array->nelems; @@ -334,8 +286,7 @@ int btf__resolve_type(const struct btf *btf, __u32 type_id) t = btf__type_by_id(btf, type_id); while (depth < MAX_RESOLVE_DEPTH && !btf_type_is_void_or_null(t) && - (IS_MODIFIER(BTF_INFO_KIND(t->info)) || - IS_VAR(BTF_INFO_KIND(t->info)))) { + (btf_is_mod(t) || btf_is_typedef(t) || btf_is_var(t))) { type_id = t->type; t = btf__type_by_id(btf, type_id); depth++; @@ -554,11 +505,11 @@ static int compare_vsi_off(const void *_a, const void *_b) static int btf_fixup_datasec(struct bpf_object *obj, struct btf *btf, struct btf_type *t) { - __u32 size = 0, off = 0, i, vars = BTF_INFO_VLEN(t->info); + __u32 size = 0, off = 0, i, vars = btf_vlen(t); const char *name = btf__name_by_offset(btf, t->name_off); const struct btf_type *t_var; struct btf_var_secinfo *vsi; - struct btf_var *var; + const struct btf_var *var; int ret; if (!name) { @@ -574,12 +525,11 @@ static int btf_fixup_datasec(struct bpf_object *obj, struct btf *btf, t->size = size; - for (i = 0, vsi = (struct btf_var_secinfo *)(t + 1); - i < vars; i++, vsi++) { + for (i = 0, vsi = btf_var_secinfos(t); i < vars; i++, vsi++) { t_var = btf__type_by_id(btf, vsi->type); - var = (struct btf_var *)(t_var + 1); + var = btf_var(t_var); - if (BTF_INFO_KIND(t_var->info) != BTF_KIND_VAR) { + if (!btf_is_var(t_var)) { pr_debug("Non-VAR type seen in section %s\n", name); return -EINVAL; } @@ -595,7 +545,8 @@ static int btf_fixup_datasec(struct bpf_object *obj, struct btf *btf, ret = bpf_object__variable_offset(obj, name, &off); if (ret) { - pr_debug("No offset found in symbol table for VAR %s\n", name); + pr_debug("No offset found in symbol table for VAR %s\n", + name); return -ENOENT; } @@ -619,7 +570,7 @@ int btf__finalize_data(struct bpf_object *obj, struct btf *btf) * is section size and global variable offset. We use * the info from the ELF itself for this purpose. */ - if (BTF_INFO_KIND(t->info) == BTF_KIND_DATASEC) { + if (btf_is_datasec(t)) { err = btf_fixup_datasec(obj, btf, t); if (err) break; @@ -774,14 +725,13 @@ int btf__get_map_kv_tids(const struct btf *btf, const char *map_name, return -EINVAL; } - if (BTF_INFO_KIND(container_type->info) != BTF_KIND_STRUCT || - BTF_INFO_VLEN(container_type->info) < 2) { + if (!btf_is_struct(container_type) || btf_vlen(container_type) < 2) { pr_warning("map:%s container_name:%s is an invalid container struct\n", map_name, container_name); return -EINVAL; } - key = (struct btf_member *)(container_type + 1); + key = btf_members(container_type); value = key + 1; key_size = btf__resolve_size(btf, key->type); @@ -831,6 +781,9 @@ static int btf_ext_setup_info(struct btf_ext *btf_ext, /* The start of the info sec (including the __u32 record_size). */ void *info; + if (ext_sec->len == 0) + return 0; + if (ext_sec->off & 0x03) { pr_debug(".BTF.ext %s section is not aligned to 4 bytes\n", ext_sec->desc); @@ -934,11 +887,24 @@ static int btf_ext_setup_line_info(struct btf_ext *btf_ext) return btf_ext_setup_info(btf_ext, ¶m); } +static int btf_ext_setup_offset_reloc(struct btf_ext *btf_ext) +{ + struct btf_ext_sec_setup_param param = { + .off = btf_ext->hdr->offset_reloc_off, + .len = btf_ext->hdr->offset_reloc_len, + .min_rec_size = sizeof(struct bpf_offset_reloc), + .ext_info = &btf_ext->offset_reloc_info, + .desc = "offset_reloc", + }; + + return btf_ext_setup_info(btf_ext, ¶m); +} + static int btf_ext_parse_hdr(__u8 *data, __u32 data_size) { const struct btf_ext_header *hdr = (struct btf_ext_header *)data; - if (data_size < offsetof(struct btf_ext_header, func_info_off) || + if (data_size < offsetofend(struct btf_ext_header, hdr_len) || data_size < hdr->hdr_len) { pr_debug("BTF.ext header not found"); return -EINVAL; @@ -996,6 +962,9 @@ struct btf_ext *btf_ext__new(__u8 *data, __u32 size) } memcpy(btf_ext->data, data, size); + if (btf_ext->hdr->hdr_len < + offsetofend(struct btf_ext_header, line_info_len)) + goto done; err = btf_ext_setup_func_info(btf_ext); if (err) goto done; @@ -1004,6 +973,13 @@ struct btf_ext *btf_ext__new(__u8 *data, __u32 size) if (err) goto done; + if (btf_ext->hdr->hdr_len < + offsetofend(struct btf_ext_header, offset_reloc_len)) + goto done; + err = btf_ext_setup_offset_reloc(btf_ext); + if (err) + goto done; + done: if (err) { btf_ext__free(btf_ext); @@ -1440,10 +1416,9 @@ static struct btf_dedup *btf_dedup_new(struct btf *btf, struct btf_ext *btf_ext, d->map[0] = 0; for (i = 1; i <= btf->nr_types; i++) { struct btf_type *t = d->btf->types[i]; - __u16 kind = BTF_INFO_KIND(t->info); /* VAR and DATASEC are never deduped and are self-canonical */ - if (kind == BTF_KIND_VAR || kind == BTF_KIND_DATASEC) + if (btf_is_var(t) || btf_is_datasec(t)) d->map[i] = i; else d->map[i] = BTF_UNPROCESSED_ID; @@ -1484,11 +1459,11 @@ static int btf_for_each_str_off(struct btf_dedup *d, str_off_fn_t fn, void *ctx) if (r) return r; - switch (BTF_INFO_KIND(t->info)) { + switch (btf_kind(t)) { case BTF_KIND_STRUCT: case BTF_KIND_UNION: { - struct btf_member *m = (struct btf_member *)(t + 1); - __u16 vlen = BTF_INFO_VLEN(t->info); + struct btf_member *m = btf_members(t); + __u16 vlen = btf_vlen(t); for (j = 0; j < vlen; j++) { r = fn(&m->name_off, ctx); @@ -1499,8 +1474,8 @@ static int btf_for_each_str_off(struct btf_dedup *d, str_off_fn_t fn, void *ctx) break; } case BTF_KIND_ENUM: { - struct btf_enum *m = (struct btf_enum *)(t + 1); - __u16 vlen = BTF_INFO_VLEN(t->info); + struct btf_enum *m = btf_enum(t); + __u16 vlen = btf_vlen(t); for (j = 0; j < vlen; j++) { r = fn(&m->name_off, ctx); @@ -1511,8 +1486,8 @@ static int btf_for_each_str_off(struct btf_dedup *d, str_off_fn_t fn, void *ctx) break; } case BTF_KIND_FUNC_PROTO: { - struct btf_param *m = (struct btf_param *)(t + 1); - __u16 vlen = BTF_INFO_VLEN(t->info); + struct btf_param *m = btf_params(t); + __u16 vlen = btf_vlen(t); for (j = 0; j < vlen; j++) { r = fn(&m->name_off, ctx); @@ -1801,16 +1776,16 @@ static long btf_hash_enum(struct btf_type *t) /* Check structural equality of two ENUMs. */ static bool btf_equal_enum(struct btf_type *t1, struct btf_type *t2) { - struct btf_enum *m1, *m2; + const struct btf_enum *m1, *m2; __u16 vlen; int i; if (!btf_equal_common(t1, t2)) return false; - vlen = BTF_INFO_VLEN(t1->info); - m1 = (struct btf_enum *)(t1 + 1); - m2 = (struct btf_enum *)(t2 + 1); + vlen = btf_vlen(t1); + m1 = btf_enum(t1); + m2 = btf_enum(t2); for (i = 0; i < vlen; i++) { if (m1->name_off != m2->name_off || m1->val != m2->val) return false; @@ -1822,8 +1797,7 @@ static bool btf_equal_enum(struct btf_type *t1, struct btf_type *t2) static inline bool btf_is_enum_fwd(struct btf_type *t) { - return BTF_INFO_KIND(t->info) == BTF_KIND_ENUM && - BTF_INFO_VLEN(t->info) == 0; + return btf_is_enum(t) && btf_vlen(t) == 0; } static bool btf_compat_enum(struct btf_type *t1, struct btf_type *t2) @@ -1843,8 +1817,8 @@ static bool btf_compat_enum(struct btf_type *t1, struct btf_type *t2) */ static long btf_hash_struct(struct btf_type *t) { - struct btf_member *member = (struct btf_member *)(t + 1); - __u32 vlen = BTF_INFO_VLEN(t->info); + const struct btf_member *member = btf_members(t); + __u32 vlen = btf_vlen(t); long h = btf_hash_common(t); int i; @@ -1864,16 +1838,16 @@ static long btf_hash_struct(struct btf_type *t) */ static bool btf_shallow_equal_struct(struct btf_type *t1, struct btf_type *t2) { - struct btf_member *m1, *m2; + const struct btf_member *m1, *m2; __u16 vlen; int i; if (!btf_equal_common(t1, t2)) return false; - vlen = BTF_INFO_VLEN(t1->info); - m1 = (struct btf_member *)(t1 + 1); - m2 = (struct btf_member *)(t2 + 1); + vlen = btf_vlen(t1); + m1 = btf_members(t1); + m2 = btf_members(t2); for (i = 0; i < vlen; i++) { if (m1->name_off != m2->name_off || m1->offset != m2->offset) return false; @@ -1890,7 +1864,7 @@ static bool btf_shallow_equal_struct(struct btf_type *t1, struct btf_type *t2) */ static long btf_hash_array(struct btf_type *t) { - struct btf_array *info = (struct btf_array *)(t + 1); + const struct btf_array *info = btf_array(t); long h = btf_hash_common(t); h = hash_combine(h, info->type); @@ -1908,13 +1882,13 @@ static long btf_hash_array(struct btf_type *t) */ static bool btf_equal_array(struct btf_type *t1, struct btf_type *t2) { - struct btf_array *info1, *info2; + const struct btf_array *info1, *info2; if (!btf_equal_common(t1, t2)) return false; - info1 = (struct btf_array *)(t1 + 1); - info2 = (struct btf_array *)(t2 + 1); + info1 = btf_array(t1); + info2 = btf_array(t2); return info1->type == info2->type && info1->index_type == info2->index_type && info1->nelems == info2->nelems; @@ -1927,14 +1901,10 @@ static bool btf_equal_array(struct btf_type *t1, struct btf_type *t2) */ static bool btf_compat_array(struct btf_type *t1, struct btf_type *t2) { - struct btf_array *info1, *info2; - if (!btf_equal_common(t1, t2)) return false; - info1 = (struct btf_array *)(t1 + 1); - info2 = (struct btf_array *)(t2 + 1); - return info1->nelems == info2->nelems; + return btf_array(t1)->nelems == btf_array(t2)->nelems; } /* @@ -1944,8 +1914,8 @@ static bool btf_compat_array(struct btf_type *t1, struct btf_type *t2) */ static long btf_hash_fnproto(struct btf_type *t) { - struct btf_param *member = (struct btf_param *)(t + 1); - __u16 vlen = BTF_INFO_VLEN(t->info); + const struct btf_param *member = btf_params(t); + __u16 vlen = btf_vlen(t); long h = btf_hash_common(t); int i; @@ -1966,16 +1936,16 @@ static long btf_hash_fnproto(struct btf_type *t) */ static bool btf_equal_fnproto(struct btf_type *t1, struct btf_type *t2) { - struct btf_param *m1, *m2; + const struct btf_param *m1, *m2; __u16 vlen; int i; if (!btf_equal_common(t1, t2)) return false; - vlen = BTF_INFO_VLEN(t1->info); - m1 = (struct btf_param *)(t1 + 1); - m2 = (struct btf_param *)(t2 + 1); + vlen = btf_vlen(t1); + m1 = btf_params(t1); + m2 = btf_params(t2); for (i = 0; i < vlen; i++) { if (m1->name_off != m2->name_off || m1->type != m2->type) return false; @@ -1992,7 +1962,7 @@ static bool btf_equal_fnproto(struct btf_type *t1, struct btf_type *t2) */ static bool btf_compat_fnproto(struct btf_type *t1, struct btf_type *t2) { - struct btf_param *m1, *m2; + const struct btf_param *m1, *m2; __u16 vlen; int i; @@ -2000,9 +1970,9 @@ static bool btf_compat_fnproto(struct btf_type *t1, struct btf_type *t2) if (t1->name_off != t2->name_off || t1->info != t2->info) return false; - vlen = BTF_INFO_VLEN(t1->info); - m1 = (struct btf_param *)(t1 + 1); - m2 = (struct btf_param *)(t2 + 1); + vlen = btf_vlen(t1); + m1 = btf_params(t1); + m2 = btf_params(t2); for (i = 0; i < vlen; i++) { if (m1->name_off != m2->name_off) return false; @@ -2028,7 +1998,7 @@ static int btf_dedup_prim_type(struct btf_dedup *d, __u32 type_id) __u32 cand_id; long h; - switch (BTF_INFO_KIND(t->info)) { + switch (btf_kind(t)) { case BTF_KIND_CONST: case BTF_KIND_VOLATILE: case BTF_KIND_RESTRICT: @@ -2141,13 +2111,13 @@ static uint32_t resolve_fwd_id(struct btf_dedup *d, uint32_t type_id) { __u32 orig_type_id = type_id; - if (BTF_INFO_KIND(d->btf->types[type_id]->info) != BTF_KIND_FWD) + if (!btf_is_fwd(d->btf->types[type_id])) return type_id; while (is_type_mapped(d, type_id) && d->map[type_id] != type_id) type_id = d->map[type_id]; - if (BTF_INFO_KIND(d->btf->types[type_id]->info) != BTF_KIND_FWD) + if (!btf_is_fwd(d->btf->types[type_id])) return type_id; return orig_type_id; @@ -2156,7 +2126,7 @@ static uint32_t resolve_fwd_id(struct btf_dedup *d, uint32_t type_id) static inline __u16 btf_fwd_kind(struct btf_type *t) { - return BTF_INFO_KFLAG(t->info) ? BTF_KIND_UNION : BTF_KIND_STRUCT; + return btf_kflag(t) ? BTF_KIND_UNION : BTF_KIND_STRUCT; } /* @@ -2277,8 +2247,8 @@ static int btf_dedup_is_equiv(struct btf_dedup *d, __u32 cand_id, cand_type = d->btf->types[cand_id]; canon_type = d->btf->types[canon_id]; - cand_kind = BTF_INFO_KIND(cand_type->info); - canon_kind = BTF_INFO_KIND(canon_type->info); + cand_kind = btf_kind(cand_type); + canon_kind = btf_kind(canon_type); if (cand_type->name_off != canon_type->name_off) return 0; @@ -2327,12 +2297,12 @@ static int btf_dedup_is_equiv(struct btf_dedup *d, __u32 cand_id, return btf_dedup_is_equiv(d, cand_type->type, canon_type->type); case BTF_KIND_ARRAY: { - struct btf_array *cand_arr, *canon_arr; + const struct btf_array *cand_arr, *canon_arr; if (!btf_compat_array(cand_type, canon_type)) return 0; - cand_arr = (struct btf_array *)(cand_type + 1); - canon_arr = (struct btf_array *)(canon_type + 1); + cand_arr = btf_array(cand_type); + canon_arr = btf_array(canon_type); eq = btf_dedup_is_equiv(d, cand_arr->index_type, canon_arr->index_type); if (eq <= 0) @@ -2342,14 +2312,14 @@ static int btf_dedup_is_equiv(struct btf_dedup *d, __u32 cand_id, case BTF_KIND_STRUCT: case BTF_KIND_UNION: { - struct btf_member *cand_m, *canon_m; + const struct btf_member *cand_m, *canon_m; __u16 vlen; if (!btf_shallow_equal_struct(cand_type, canon_type)) return 0; - vlen = BTF_INFO_VLEN(cand_type->info); - cand_m = (struct btf_member *)(cand_type + 1); - canon_m = (struct btf_member *)(canon_type + 1); + vlen = btf_vlen(cand_type); + cand_m = btf_members(cand_type); + canon_m = btf_members(canon_type); for (i = 0; i < vlen; i++) { eq = btf_dedup_is_equiv(d, cand_m->type, canon_m->type); if (eq <= 0) @@ -2362,7 +2332,7 @@ static int btf_dedup_is_equiv(struct btf_dedup *d, __u32 cand_id, } case BTF_KIND_FUNC_PROTO: { - struct btf_param *cand_p, *canon_p; + const struct btf_param *cand_p, *canon_p; __u16 vlen; if (!btf_compat_fnproto(cand_type, canon_type)) @@ -2370,9 +2340,9 @@ static int btf_dedup_is_equiv(struct btf_dedup *d, __u32 cand_id, eq = btf_dedup_is_equiv(d, cand_type->type, canon_type->type); if (eq <= 0) return eq; - vlen = BTF_INFO_VLEN(cand_type->info); - cand_p = (struct btf_param *)(cand_type + 1); - canon_p = (struct btf_param *)(canon_type + 1); + vlen = btf_vlen(cand_type); + cand_p = btf_params(cand_type); + canon_p = btf_params(canon_type); for (i = 0; i < vlen; i++) { eq = btf_dedup_is_equiv(d, cand_p->type, canon_p->type); if (eq <= 0) @@ -2427,8 +2397,8 @@ static void btf_dedup_merge_hypot_map(struct btf_dedup *d) targ_type_id = d->hypot_map[cand_type_id]; t_id = resolve_type_id(d, targ_type_id); c_id = resolve_type_id(d, cand_type_id); - t_kind = BTF_INFO_KIND(d->btf->types[t_id]->info); - c_kind = BTF_INFO_KIND(d->btf->types[c_id]->info); + t_kind = btf_kind(d->btf->types[t_id]); + c_kind = btf_kind(d->btf->types[c_id]); /* * Resolve FWD into STRUCT/UNION. * It's ok to resolve FWD into STRUCT/UNION that's not yet @@ -2497,7 +2467,7 @@ static int btf_dedup_struct_type(struct btf_dedup *d, __u32 type_id) return 0; t = d->btf->types[type_id]; - kind = BTF_INFO_KIND(t->info); + kind = btf_kind(t); if (kind != BTF_KIND_STRUCT && kind != BTF_KIND_UNION) return 0; @@ -2592,7 +2562,7 @@ static int btf_dedup_ref_type(struct btf_dedup *d, __u32 type_id) t = d->btf->types[type_id]; d->map[type_id] = BTF_IN_PROGRESS_ID; - switch (BTF_INFO_KIND(t->info)) { + switch (btf_kind(t)) { case BTF_KIND_CONST: case BTF_KIND_VOLATILE: case BTF_KIND_RESTRICT: @@ -2616,7 +2586,7 @@ static int btf_dedup_ref_type(struct btf_dedup *d, __u32 type_id) break; case BTF_KIND_ARRAY: { - struct btf_array *info = (struct btf_array *)(t + 1); + struct btf_array *info = btf_array(t); ref_type_id = btf_dedup_ref_type(d, info->type); if (ref_type_id < 0) @@ -2650,8 +2620,8 @@ static int btf_dedup_ref_type(struct btf_dedup *d, __u32 type_id) return ref_type_id; t->type = ref_type_id; - vlen = BTF_INFO_VLEN(t->info); - param = (struct btf_param *)(t + 1); + vlen = btf_vlen(t); + param = btf_params(t); for (i = 0; i < vlen; i++) { ref_type_id = btf_dedup_ref_type(d, param->type); if (ref_type_id < 0) @@ -2791,7 +2761,7 @@ static int btf_dedup_remap_type(struct btf_dedup *d, __u32 type_id) struct btf_type *t = d->btf->types[type_id]; int i, r; - switch (BTF_INFO_KIND(t->info)) { + switch (btf_kind(t)) { case BTF_KIND_INT: case BTF_KIND_ENUM: break; @@ -2811,7 +2781,7 @@ static int btf_dedup_remap_type(struct btf_dedup *d, __u32 type_id) break; case BTF_KIND_ARRAY: { - struct btf_array *arr_info = (struct btf_array *)(t + 1); + struct btf_array *arr_info = btf_array(t); r = btf_dedup_remap_type_id(d, arr_info->type); if (r < 0) @@ -2826,8 +2796,8 @@ static int btf_dedup_remap_type(struct btf_dedup *d, __u32 type_id) case BTF_KIND_STRUCT: case BTF_KIND_UNION: { - struct btf_member *member = (struct btf_member *)(t + 1); - __u16 vlen = BTF_INFO_VLEN(t->info); + struct btf_member *member = btf_members(t); + __u16 vlen = btf_vlen(t); for (i = 0; i < vlen; i++) { r = btf_dedup_remap_type_id(d, member->type); @@ -2840,8 +2810,8 @@ static int btf_dedup_remap_type(struct btf_dedup *d, __u32 type_id) } case BTF_KIND_FUNC_PROTO: { - struct btf_param *param = (struct btf_param *)(t + 1); - __u16 vlen = BTF_INFO_VLEN(t->info); + struct btf_param *param = btf_params(t); + __u16 vlen = btf_vlen(t); r = btf_dedup_remap_type_id(d, t->type); if (r < 0) @@ -2859,8 +2829,8 @@ static int btf_dedup_remap_type(struct btf_dedup *d, __u32 type_id) } case BTF_KIND_DATASEC: { - struct btf_var_secinfo *var = (struct btf_var_secinfo *)(t + 1); - __u16 vlen = BTF_INFO_VLEN(t->info); + struct btf_var_secinfo *var = btf_var_secinfos(t); + __u16 vlen = btf_vlen(t); for (i = 0; i < vlen; i++) { r = btf_dedup_remap_type_id(d, var->type); diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h index 88a52ae56fc6..9cb44b4fbf60 100644 --- a/tools/lib/bpf/btf.h +++ b/tools/lib/bpf/btf.h @@ -5,6 +5,7 @@ #define __LIBBPF_BTF_H #include <stdarg.h> +#include <linux/btf.h> #include <linux/types.h> #ifdef __cplusplus @@ -57,6 +58,10 @@ struct btf_ext_header { __u32 func_info_len; __u32 line_info_off; __u32 line_info_len; + + /* optional part of .BTF.ext header */ + __u32 offset_reloc_off; + __u32 offset_reloc_len; }; LIBBPF_API void btf__free(struct btf *btf); @@ -120,6 +125,183 @@ LIBBPF_API void btf_dump__free(struct btf_dump *d); LIBBPF_API int btf_dump__dump_type(struct btf_dump *d, __u32 id); +/* + * A set of helpers for easier BTF types handling + */ +static inline __u16 btf_kind(const struct btf_type *t) +{ + return BTF_INFO_KIND(t->info); +} + +static inline __u16 btf_vlen(const struct btf_type *t) +{ + return BTF_INFO_VLEN(t->info); +} + +static inline bool btf_kflag(const struct btf_type *t) +{ + return BTF_INFO_KFLAG(t->info); +} + +static inline bool btf_is_int(const struct btf_type *t) +{ + return btf_kind(t) == BTF_KIND_INT; +} + +static inline bool btf_is_ptr(const struct btf_type *t) +{ + return btf_kind(t) == BTF_KIND_PTR; +} + +static inline bool btf_is_array(const struct btf_type *t) +{ + return btf_kind(t) == BTF_KIND_ARRAY; +} + +static inline bool btf_is_struct(const struct btf_type *t) +{ + return btf_kind(t) == BTF_KIND_STRUCT; +} + +static inline bool btf_is_union(const struct btf_type *t) +{ + return btf_kind(t) == BTF_KIND_UNION; +} + +static inline bool btf_is_composite(const struct btf_type *t) +{ + __u16 kind = btf_kind(t); + + return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION; +} + +static inline bool btf_is_enum(const struct btf_type *t) +{ + return btf_kind(t) == BTF_KIND_ENUM; +} + +static inline bool btf_is_fwd(const struct btf_type *t) +{ + return btf_kind(t) == BTF_KIND_FWD; +} + +static inline bool btf_is_typedef(const struct btf_type *t) +{ + return btf_kind(t) == BTF_KIND_TYPEDEF; +} + +static inline bool btf_is_volatile(const struct btf_type *t) +{ + return btf_kind(t) == BTF_KIND_VOLATILE; +} + +static inline bool btf_is_const(const struct btf_type *t) +{ + return btf_kind(t) == BTF_KIND_CONST; +} + +static inline bool btf_is_restrict(const struct btf_type *t) +{ + return btf_kind(t) == BTF_KIND_RESTRICT; +} + +static inline bool btf_is_mod(const struct btf_type *t) +{ + __u16 kind = btf_kind(t); + + return kind == BTF_KIND_VOLATILE || + kind == BTF_KIND_CONST || + kind == BTF_KIND_RESTRICT; +} + +static inline bool btf_is_func(const struct btf_type *t) +{ + return btf_kind(t) == BTF_KIND_FUNC; +} + +static inline bool btf_is_func_proto(const struct btf_type *t) +{ + return btf_kind(t) == BTF_KIND_FUNC_PROTO; +} + +static inline bool btf_is_var(const struct btf_type *t) +{ + return btf_kind(t) == BTF_KIND_VAR; +} + +static inline bool btf_is_datasec(const struct btf_type *t) +{ + return btf_kind(t) == BTF_KIND_DATASEC; +} + +static inline __u8 btf_int_encoding(const struct btf_type *t) +{ + return BTF_INT_ENCODING(*(__u32 *)(t + 1)); +} + +static inline __u8 btf_int_offset(const struct btf_type *t) +{ + return BTF_INT_OFFSET(*(__u32 *)(t + 1)); +} + +static inline __u8 btf_int_bits(const struct btf_type *t) +{ + return BTF_INT_BITS(*(__u32 *)(t + 1)); +} + +static inline struct btf_array *btf_array(const struct btf_type *t) +{ + return (struct btf_array *)(t + 1); +} + +static inline struct btf_enum *btf_enum(const struct btf_type *t) +{ + return (struct btf_enum *)(t + 1); +} + +static inline struct btf_member *btf_members(const struct btf_type *t) +{ + return (struct btf_member *)(t + 1); +} + +/* Get bit offset of a member with specified index. */ +static inline __u32 btf_member_bit_offset(const struct btf_type *t, + __u32 member_idx) +{ + const struct btf_member *m = btf_members(t) + member_idx; + bool kflag = btf_kflag(t); + + return kflag ? BTF_MEMBER_BIT_OFFSET(m->offset) : m->offset; +} +/* + * Get bitfield size of a member, assuming t is BTF_KIND_STRUCT or + * BTF_KIND_UNION. If member is not a bitfield, zero is returned. + */ +static inline __u32 btf_member_bitfield_size(const struct btf_type *t, + __u32 member_idx) +{ + const struct btf_member *m = btf_members(t) + member_idx; + bool kflag = btf_kflag(t); + + return kflag ? BTF_MEMBER_BITFIELD_SIZE(m->offset) : 0; +} + +static inline struct btf_param *btf_params(const struct btf_type *t) +{ + return (struct btf_param *)(t + 1); +} + +static inline struct btf_var *btf_var(const struct btf_type *t) +{ + return (struct btf_var *)(t + 1); +} + +static inline struct btf_var_secinfo * +btf_var_secinfos(const struct btf_type *t) +{ + return (struct btf_var_secinfo *)(t + 1); +} + #ifdef __cplusplus } /* extern "C" */ #endif diff --git a/tools/lib/bpf/btf_dump.c b/tools/lib/bpf/btf_dump.c index 7065bb5b2752..715967762312 100644 --- a/tools/lib/bpf/btf_dump.c +++ b/tools/lib/bpf/btf_dump.c @@ -100,21 +100,6 @@ static bool str_equal_fn(const void *a, const void *b, void *ctx) return strcmp(a, b) == 0; } -static __u16 btf_kind_of(const struct btf_type *t) -{ - return BTF_INFO_KIND(t->info); -} - -static __u16 btf_vlen_of(const struct btf_type *t) -{ - return BTF_INFO_VLEN(t->info); -} - -static bool btf_kflag_of(const struct btf_type *t) -{ - return BTF_INFO_KFLAG(t->info); -} - static const char *btf_name_of(const struct btf_dump *d, __u32 name_off) { return btf__name_by_offset(d->btf, name_off); @@ -349,7 +334,7 @@ static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr) */ struct btf_dump_type_aux_state *tstate = &d->type_states[id]; const struct btf_type *t; - __u16 kind, vlen; + __u16 vlen; int err, i; /* return true, letting typedefs know that it's ok to be emitted */ @@ -357,18 +342,16 @@ static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr) return 1; t = btf__type_by_id(d->btf, id); - kind = btf_kind_of(t); if (tstate->order_state == ORDERING) { /* type loop, but resolvable through fwd declaration */ - if ((kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION) && - through_ptr && t->name_off != 0) + if (btf_is_composite(t) && through_ptr && t->name_off != 0) return 0; pr_warning("unsatisfiable type cycle, id:[%u]\n", id); return -ELOOP; } - switch (kind) { + switch (btf_kind(t)) { case BTF_KIND_INT: tstate->order_state = ORDERED; return 0; @@ -378,14 +361,12 @@ static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr) tstate->order_state = ORDERED; return err; - case BTF_KIND_ARRAY: { - const struct btf_array *a = (void *)(t + 1); + case BTF_KIND_ARRAY: + return btf_dump_order_type(d, btf_array(t)->type, through_ptr); - return btf_dump_order_type(d, a->type, through_ptr); - } case BTF_KIND_STRUCT: case BTF_KIND_UNION: { - const struct btf_member *m = (void *)(t + 1); + const struct btf_member *m = btf_members(t); /* * struct/union is part of strong link, only if it's embedded * (so no ptr in a path) or it's anonymous (so has to be @@ -396,7 +377,7 @@ static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr) tstate->order_state = ORDERING; - vlen = btf_vlen_of(t); + vlen = btf_vlen(t); for (i = 0; i < vlen; i++, m++) { err = btf_dump_order_type(d, m->type, false); if (err < 0) @@ -447,7 +428,7 @@ static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr) return btf_dump_order_type(d, t->type, through_ptr); case BTF_KIND_FUNC_PROTO: { - const struct btf_param *p = (void *)(t + 1); + const struct btf_param *p = btf_params(t); bool is_strong; err = btf_dump_order_type(d, t->type, through_ptr); @@ -455,7 +436,7 @@ static int btf_dump_order_type(struct btf_dump *d, __u32 id, bool through_ptr) return err; is_strong = err > 0; - vlen = btf_vlen_of(t); + vlen = btf_vlen(t); for (i = 0; i < vlen; i++, p++) { err = btf_dump_order_type(d, p->type, through_ptr); if (err < 0) @@ -553,7 +534,7 @@ static void btf_dump_emit_type(struct btf_dump *d, __u32 id, __u32 cont_id) return; t = btf__type_by_id(d->btf, id); - kind = btf_kind_of(t); + kind = btf_kind(t); if (top_level_def && t->name_off == 0) { pr_warning("unexpected nameless definition, id:[%u]\n", id); @@ -618,12 +599,9 @@ static void btf_dump_emit_type(struct btf_dump *d, __u32 id, __u32 cont_id) case BTF_KIND_RESTRICT: btf_dump_emit_type(d, t->type, cont_id); break; - case BTF_KIND_ARRAY: { - const struct btf_array *a = (void *)(t + 1); - - btf_dump_emit_type(d, a->type, cont_id); + case BTF_KIND_ARRAY: + btf_dump_emit_type(d, btf_array(t)->type, cont_id); break; - } case BTF_KIND_FWD: btf_dump_emit_fwd_def(d, id, t); btf_dump_printf(d, ";\n\n"); @@ -656,8 +634,8 @@ static void btf_dump_emit_type(struct btf_dump *d, __u32 id, __u32 cont_id) * applicable */ if (top_level_def || t->name_off == 0) { - const struct btf_member *m = (void *)(t + 1); - __u16 vlen = btf_vlen_of(t); + const struct btf_member *m = btf_members(t); + __u16 vlen = btf_vlen(t); int i, new_cont_id; new_cont_id = t->name_off == 0 ? cont_id : id; @@ -678,8 +656,8 @@ 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 = (void *)(t + 1); - __u16 vlen = btf_vlen_of(t); + const struct btf_param *p = btf_params(t); + __u16 vlen = btf_vlen(t); int i; btf_dump_emit_type(d, t->type, cont_id); @@ -696,7 +674,7 @@ static void btf_dump_emit_type(struct btf_dump *d, __u32 id, __u32 cont_id) static int btf_align_of(const struct btf *btf, __u32 id) { const struct btf_type *t = btf__type_by_id(btf, id); - __u16 kind = btf_kind_of(t); + __u16 kind = btf_kind(t); switch (kind) { case BTF_KIND_INT: @@ -709,15 +687,12 @@ static int btf_align_of(const struct btf *btf, __u32 id) case BTF_KIND_CONST: case BTF_KIND_RESTRICT: return btf_align_of(btf, t->type); - case BTF_KIND_ARRAY: { - const struct btf_array *a = (void *)(t + 1); - - return btf_align_of(btf, a->type); - } + case BTF_KIND_ARRAY: + return btf_align_of(btf, btf_array(t)->type); case BTF_KIND_STRUCT: case BTF_KIND_UNION: { - const struct btf_member *m = (void *)(t + 1); - __u16 vlen = btf_vlen_of(t); + const struct btf_member *m = btf_members(t); + __u16 vlen = btf_vlen(t); int i, align = 1; for (i = 0; i < vlen; i++, m++) @@ -726,7 +701,7 @@ static int btf_align_of(const struct btf *btf, __u32 id) return align; } default: - pr_warning("unsupported BTF_KIND:%u\n", btf_kind_of(t)); + pr_warning("unsupported BTF_KIND:%u\n", btf_kind(t)); return 1; } } @@ -737,20 +712,18 @@ static bool btf_is_struct_packed(const struct btf *btf, __u32 id, const struct btf_member *m; int align, i, bit_sz; __u16 vlen; - bool kflag; align = btf_align_of(btf, id); /* size of a non-packed struct has to be a multiple of its alignment*/ if (t->size % align) return true; - m = (void *)(t + 1); - kflag = btf_kflag_of(t); - vlen = btf_vlen_of(t); + m = btf_members(t); + vlen = btf_vlen(t); /* all non-bitfield fields have to be naturally aligned */ for (i = 0; i < vlen; i++, m++) { align = btf_align_of(btf, m->type); - bit_sz = kflag ? BTF_MEMBER_BITFIELD_SIZE(m->offset) : 0; + bit_sz = btf_member_bitfield_size(t, i); if (bit_sz == 0 && m->offset % (8 * align) != 0) return true; } @@ -807,7 +780,7 @@ 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_kind_of(t) == BTF_KIND_STRUCT ? "struct" : "union", + btf_is_struct(t) ? "struct" : "union", btf_dump_type_name(d, id)); } @@ -816,12 +789,11 @@ static void btf_dump_emit_struct_def(struct btf_dump *d, const struct btf_type *t, int lvl) { - const struct btf_member *m = (void *)(t + 1); - bool kflag = btf_kflag_of(t), is_struct; + const struct btf_member *m = btf_members(t); + bool is_struct = btf_is_struct(t); int align, i, packed, off = 0; - __u16 vlen = btf_vlen_of(t); + __u16 vlen = btf_vlen(t); - is_struct = btf_kind_of(t) == BTF_KIND_STRUCT; packed = is_struct ? btf_is_struct_packed(d->btf, id, t) : 0; align = packed ? 1 : btf_align_of(d->btf, id); @@ -835,8 +807,8 @@ static void btf_dump_emit_struct_def(struct btf_dump *d, int m_off, m_sz; fname = btf_name_of(d, m->name_off); - m_sz = kflag ? BTF_MEMBER_BITFIELD_SIZE(m->offset) : 0; - m_off = kflag ? BTF_MEMBER_BIT_OFFSET(m->offset) : m->offset; + m_sz = btf_member_bitfield_size(t, i); + m_off = btf_member_bit_offset(t, i); align = packed ? 1 : btf_align_of(d->btf, m->type); btf_dump_emit_bit_padding(d, off, m_off, m_sz, align, lvl + 1); @@ -870,8 +842,8 @@ static void btf_dump_emit_enum_def(struct btf_dump *d, __u32 id, const struct btf_type *t, int lvl) { - const struct btf_enum *v = (void *)(t+1); - __u16 vlen = btf_vlen_of(t); + const struct btf_enum *v = btf_enum(t); + __u16 vlen = btf_vlen(t); const char *name; size_t dup_cnt; int i; @@ -905,7 +877,7 @@ static void btf_dump_emit_fwd_def(struct btf_dump *d, __u32 id, { const char *name = btf_dump_type_name(d, id); - if (btf_kflag_of(t)) + if (btf_kflag(t)) btf_dump_printf(d, "union %s", name); else btf_dump_printf(d, "struct %s", name); @@ -987,7 +959,6 @@ static void btf_dump_emit_type_decl(struct btf_dump *d, __u32 id, struct id_stack decl_stack; const struct btf_type *t; int err, stack_start; - __u16 kind; stack_start = d->decl_stack_cnt; for (;;) { @@ -1008,8 +979,7 @@ static void btf_dump_emit_type_decl(struct btf_dump *d, __u32 id, break; t = btf__type_by_id(d->btf, id); - kind = btf_kind_of(t); - switch (kind) { + switch (btf_kind(t)) { case BTF_KIND_PTR: case BTF_KIND_VOLATILE: case BTF_KIND_CONST: @@ -1017,12 +987,9 @@ static void btf_dump_emit_type_decl(struct btf_dump *d, __u32 id, case BTF_KIND_FUNC_PROTO: id = t->type; break; - case BTF_KIND_ARRAY: { - const struct btf_array *a = (void *)(t + 1); - - id = a->type; + case BTF_KIND_ARRAY: + id = btf_array(t)->type; break; - } case BTF_KIND_INT: case BTF_KIND_ENUM: case BTF_KIND_FWD: @@ -1032,7 +999,7 @@ static void btf_dump_emit_type_decl(struct btf_dump *d, __u32 id, goto done; default: pr_warning("unexpected type in decl chain, kind:%u, id:[%u]\n", - kind, id); + btf_kind(t), id); goto done; } } @@ -1070,7 +1037,7 @@ static void btf_dump_emit_mods(struct btf_dump *d, struct id_stack *decl_stack) id = decl_stack->ids[decl_stack->cnt - 1]; t = btf__type_by_id(d->btf, id); - switch (btf_kind_of(t)) { + switch (btf_kind(t)) { case BTF_KIND_VOLATILE: btf_dump_printf(d, "volatile "); break; @@ -1087,20 +1054,6 @@ static void btf_dump_emit_mods(struct btf_dump *d, struct id_stack *decl_stack) } } -static bool btf_is_mod_kind(const struct btf *btf, __u32 id) -{ - const struct btf_type *t = btf__type_by_id(btf, id); - - switch (btf_kind_of(t)) { - case BTF_KIND_VOLATILE: - case BTF_KIND_CONST: - case BTF_KIND_RESTRICT: - return true; - default: - return false; - } -} - static void btf_dump_emit_name(const struct btf_dump *d, const char *name, bool last_was_ptr) { @@ -1139,7 +1092,7 @@ static void btf_dump_emit_type_chain(struct btf_dump *d, } t = btf__type_by_id(d->btf, id); - kind = btf_kind_of(t); + kind = btf_kind(t); switch (kind) { case BTF_KIND_INT: @@ -1185,7 +1138,7 @@ static void btf_dump_emit_type_chain(struct btf_dump *d, btf_dump_printf(d, " restrict"); break; case BTF_KIND_ARRAY: { - const struct btf_array *a = (void *)(t + 1); + const struct btf_array *a = btf_array(t); const struct btf_type *next_t; __u32 next_id; bool multidim; @@ -1201,7 +1154,8 @@ static void btf_dump_emit_type_chain(struct btf_dump *d, */ while (decls->cnt) { next_id = decls->ids[decls->cnt - 1]; - if (btf_is_mod_kind(d->btf, next_id)) + next_t = btf__type_by_id(d->btf, next_id); + if (btf_is_mod(next_t)) decls->cnt--; else break; @@ -1214,7 +1168,7 @@ static void btf_dump_emit_type_chain(struct btf_dump *d, } next_t = btf__type_by_id(d->btf, next_id); - multidim = btf_kind_of(next_t) == BTF_KIND_ARRAY; + multidim = btf_is_array(next_t); /* we need space if we have named non-pointer */ if (fname[0] && !last_was_ptr) btf_dump_printf(d, " "); @@ -1228,8 +1182,8 @@ static void btf_dump_emit_type_chain(struct btf_dump *d, return; } case BTF_KIND_FUNC_PROTO: { - const struct btf_param *p = (void *)(t + 1); - __u16 vlen = btf_vlen_of(t); + const struct btf_param *p = btf_params(t); + __u16 vlen = btf_vlen(t); int i; btf_dump_emit_mods(d, decls); diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index ead915aec349..3abf2dd1b3b5 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -38,6 +38,7 @@ #include <sys/stat.h> #include <sys/types.h> #include <sys/vfs.h> +#include <sys/utsname.h> #include <tools/libc_compat.h> #include <libelf.h> #include <gelf.h> @@ -47,6 +48,7 @@ #include "btf.h" #include "str_error.h" #include "libbpf_internal.h" +#include "hashmap.h" #ifndef EM_BPF #define EM_BPF 247 @@ -1015,23 +1017,21 @@ static int bpf_object__init_user_maps(struct bpf_object *obj, bool strict) return 0; } -static const struct btf_type *skip_mods_and_typedefs(const struct btf *btf, - __u32 id) +static const struct btf_type * +skip_mods_and_typedefs(const struct btf *btf, __u32 id, __u32 *res_id) { const struct btf_type *t = btf__type_by_id(btf, id); - while (true) { - switch (BTF_INFO_KIND(t->info)) { - case BTF_KIND_VOLATILE: - case BTF_KIND_CONST: - case BTF_KIND_RESTRICT: - case BTF_KIND_TYPEDEF: - t = btf__type_by_id(btf, t->type); - break; - default: - return t; - } + if (res_id) + *res_id = id; + + while (btf_is_mod(t) || btf_is_typedef(t)) { + if (res_id) + *res_id = t->type; + t = btf__type_by_id(btf, t->type); } + + return t; } /* @@ -1044,14 +1044,14 @@ static const struct btf_type *skip_mods_and_typedefs(const struct btf *btf, static bool get_map_field_int(const char *map_name, const struct btf *btf, const struct btf_type *def, const struct btf_member *m, __u32 *res) { - const struct btf_type *t = skip_mods_and_typedefs(btf, m->type); + const struct btf_type *t = skip_mods_and_typedefs(btf, m->type, NULL); const char *name = btf__name_by_offset(btf, m->name_off); const struct btf_array *arr_info; const struct btf_type *arr_t; - if (BTF_INFO_KIND(t->info) != BTF_KIND_PTR) { + if (!btf_is_ptr(t)) { pr_warning("map '%s': attr '%s': expected PTR, got %u.\n", - map_name, name, BTF_INFO_KIND(t->info)); + map_name, name, btf_kind(t)); return false; } @@ -1061,12 +1061,12 @@ static bool get_map_field_int(const char *map_name, const struct btf *btf, map_name, name, t->type); return false; } - if (BTF_INFO_KIND(arr_t->info) != BTF_KIND_ARRAY) { + if (!btf_is_array(arr_t)) { pr_warning("map '%s': attr '%s': expected ARRAY, got %u.\n", - map_name, name, BTF_INFO_KIND(arr_t->info)); + map_name, name, btf_kind(arr_t)); return false; } - arr_info = (const void *)(arr_t + 1); + arr_info = btf_array(arr_t); *res = arr_info->nelems; return true; } @@ -1084,11 +1084,11 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj, struct bpf_map *map; int vlen, i; - vi = (const struct btf_var_secinfo *)(const void *)(sec + 1) + var_idx; + vi = btf_var_secinfos(sec) + var_idx; var = btf__type_by_id(obj->btf, vi->type); - var_extra = (const void *)(var + 1); + var_extra = btf_var(var); map_name = btf__name_by_offset(obj->btf, var->name_off); - vlen = BTF_INFO_VLEN(var->info); + vlen = btf_vlen(var); if (map_name == NULL || map_name[0] == '\0') { pr_warning("map #%d: empty name.\n", var_idx); @@ -1098,9 +1098,9 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj, pr_warning("map '%s' BTF data is corrupted.\n", map_name); return -EINVAL; } - if (BTF_INFO_KIND(var->info) != BTF_KIND_VAR) { + if (!btf_is_var(var)) { pr_warning("map '%s': unexpected var kind %u.\n", - map_name, BTF_INFO_KIND(var->info)); + map_name, btf_kind(var)); return -EINVAL; } if (var_extra->linkage != BTF_VAR_GLOBAL_ALLOCATED && @@ -1110,10 +1110,10 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj, return -EOPNOTSUPP; } - def = skip_mods_and_typedefs(obj->btf, var->type); - if (BTF_INFO_KIND(def->info) != BTF_KIND_STRUCT) { + def = skip_mods_and_typedefs(obj->btf, var->type, NULL); + if (!btf_is_struct(def)) { pr_warning("map '%s': unexpected def kind %u.\n", - map_name, BTF_INFO_KIND(var->info)); + map_name, btf_kind(var)); return -EINVAL; } if (def->size > vi->size) { @@ -1136,8 +1136,8 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj, pr_debug("map '%s': at sec_idx %d, offset %zu.\n", map_name, map->sec_idx, map->sec_offset); - vlen = BTF_INFO_VLEN(def->info); - m = (const void *)(def + 1); + vlen = btf_vlen(def); + m = btf_members(def); for (i = 0; i < vlen; i++, m++) { const char *name = btf__name_by_offset(obj->btf, m->name_off); @@ -1187,9 +1187,9 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj, map_name, m->type); return -EINVAL; } - if (BTF_INFO_KIND(t->info) != BTF_KIND_PTR) { + if (!btf_is_ptr(t)) { pr_warning("map '%s': key spec is not PTR: %u.\n", - map_name, BTF_INFO_KIND(t->info)); + map_name, btf_kind(t)); return -EINVAL; } sz = btf__resolve_size(obj->btf, t->type); @@ -1230,9 +1230,9 @@ static int bpf_object__init_user_btf_map(struct bpf_object *obj, map_name, m->type); return -EINVAL; } - if (BTF_INFO_KIND(t->info) != BTF_KIND_PTR) { + if (!btf_is_ptr(t)) { pr_warning("map '%s': value spec is not PTR: %u.\n", - map_name, BTF_INFO_KIND(t->info)); + map_name, btf_kind(t)); return -EINVAL; } sz = btf__resolve_size(obj->btf, t->type); @@ -1293,7 +1293,7 @@ static int bpf_object__init_user_btf_maps(struct bpf_object *obj, bool strict) nr_types = btf__get_nr_types(obj->btf); for (i = 1; i <= nr_types; i++) { t = btf__type_by_id(obj->btf, i); - if (BTF_INFO_KIND(t->info) != BTF_KIND_DATASEC) + if (!btf_is_datasec(t)) continue; name = btf__name_by_offset(obj->btf, t->name_off); if (strcmp(name, MAPS_ELF_SEC) == 0) { @@ -1307,7 +1307,7 @@ static int bpf_object__init_user_btf_maps(struct bpf_object *obj, bool strict) return -ENOENT; } - vlen = BTF_INFO_VLEN(sec->info); + vlen = btf_vlen(sec); for (i = 0; i < vlen; i++) { err = bpf_object__init_user_btf_map(obj, sec, i, obj->efile.btf_maps_shndx, @@ -1368,24 +1368,22 @@ static void bpf_object__sanitize_btf(struct bpf_object *obj) struct btf *btf = obj->btf; struct btf_type *t; int i, j, vlen; - __u16 kind; if (!obj->btf || (has_func && has_datasec)) return; for (i = 1; i <= btf__get_nr_types(btf); i++) { t = (struct btf_type *)btf__type_by_id(btf, i); - kind = BTF_INFO_KIND(t->info); - if (!has_datasec && kind == BTF_KIND_VAR) { + if (!has_datasec && btf_is_var(t)) { /* replace VAR with INT */ t->info = BTF_INFO_ENC(BTF_KIND_INT, 0, 0); t->size = sizeof(int); - *(int *)(t+1) = BTF_INT_ENC(0, 0, 32); - } else if (!has_datasec && kind == BTF_KIND_DATASEC) { + *(int *)(t + 1) = BTF_INT_ENC(0, 0, 32); + } else if (!has_datasec && btf_is_datasec(t)) { /* replace DATASEC with STRUCT */ - struct btf_var_secinfo *v = (void *)(t + 1); - struct btf_member *m = (void *)(t + 1); + const struct btf_var_secinfo *v = btf_var_secinfos(t); + struct btf_member *m = btf_members(t); struct btf_type *vt; char *name; @@ -1396,7 +1394,7 @@ static void bpf_object__sanitize_btf(struct bpf_object *obj) name++; } - vlen = BTF_INFO_VLEN(t->info); + vlen = btf_vlen(t); t->info = BTF_INFO_ENC(BTF_KIND_STRUCT, 0, vlen); for (j = 0; j < vlen; j++, v++, m++) { /* order of field assignments is important */ @@ -1406,12 +1404,12 @@ static void bpf_object__sanitize_btf(struct bpf_object *obj) vt = (void *)btf__type_by_id(btf, v->type); m->name_off = vt->name_off; } - } else if (!has_func && kind == BTF_KIND_FUNC_PROTO) { + } else if (!has_func && btf_is_func_proto(t)) { /* replace FUNC_PROTO with ENUM */ - vlen = BTF_INFO_VLEN(t->info); + vlen = btf_vlen(t); t->info = BTF_INFO_ENC(BTF_KIND_ENUM, 0, vlen); t->size = sizeof(__u32); /* kernel enforced */ - } else if (!has_func && kind == BTF_KIND_FUNC) { + } else if (!has_func && btf_is_func(t)) { /* replace FUNC with TYPEDEF */ t->info = BTF_INFO_ENC(BTF_KIND_TYPEDEF, 0, 0); } @@ -2292,6 +2290,844 @@ bpf_program_reloc_btf_ext(struct bpf_program *prog, struct bpf_object *obj, return 0; } +#define BPF_CORE_SPEC_MAX_LEN 64 + +/* represents BPF CO-RE field or array element accessor */ +struct bpf_core_accessor { + __u32 type_id; /* struct/union type or array element type */ + __u32 idx; /* field index or array index */ + const char *name; /* field name or NULL for array accessor */ +}; + +struct bpf_core_spec { + const struct btf *btf; + /* high-level spec: named fields and array indices only */ + struct bpf_core_accessor spec[BPF_CORE_SPEC_MAX_LEN]; + /* high-level spec length */ + int len; + /* raw, low-level spec: 1-to-1 with accessor spec string */ + int raw_spec[BPF_CORE_SPEC_MAX_LEN]; + /* raw spec length */ + int raw_len; + /* field byte offset represented by spec */ + __u32 offset; +}; + +static bool str_is_empty(const char *s) +{ + return !s || !s[0]; +} + +/* + * Turn bpf_offset_reloc into a low- and high-level spec representation, + * validating correctness along the way, as well as calculating resulting + * field offset (in bytes), specified by accessor string. Low-level spec + * captures every single level of nestedness, including traversing anonymous + * struct/union members. High-level one only captures semantically meaningful + * "turning points": named fields and array indicies. + * E.g., for this case: + * + * struct sample { + * int __unimportant; + * struct { + * int __1; + * int __2; + * int a[7]; + * }; + * }; + * + * struct sample *s = ...; + * + * int x = &s->a[3]; // access string = '0:1:2:3' + * + * Low-level spec has 1:1 mapping with each element of access string (it's + * just a parsed access string representation): [0, 1, 2, 3]. + * + * High-level spec will capture only 3 points: + * - intial zero-index access by pointer (&s->... is the same as &s[0]...); + * - field 'a' access (corresponds to '2' in low-level spec); + * - array element #3 access (corresponds to '3' in low-level spec). + * + */ +static int bpf_core_spec_parse(const struct btf *btf, + __u32 type_id, + const char *spec_str, + struct bpf_core_spec *spec) +{ + int access_idx, parsed_len, i; + const struct btf_type *t; + const char *name; + __u32 id; + __s64 sz; + + if (str_is_empty(spec_str) || *spec_str == ':') + return -EINVAL; + + memset(spec, 0, sizeof(*spec)); + spec->btf = btf; + + /* parse spec_str="0:1:2:3:4" into array raw_spec=[0, 1, 2, 3, 4] */ + while (*spec_str) { + if (*spec_str == ':') + ++spec_str; + if (sscanf(spec_str, "%d%n", &access_idx, &parsed_len) != 1) + return -EINVAL; + if (spec->raw_len == BPF_CORE_SPEC_MAX_LEN) + return -E2BIG; + spec_str += parsed_len; + spec->raw_spec[spec->raw_len++] = access_idx; + } + + if (spec->raw_len == 0) + return -EINVAL; + + /* first spec value is always reloc type array index */ + t = skip_mods_and_typedefs(btf, type_id, &id); + if (!t) + return -EINVAL; + + access_idx = spec->raw_spec[0]; + spec->spec[0].type_id = id; + spec->spec[0].idx = access_idx; + spec->len++; + + sz = btf__resolve_size(btf, id); + if (sz < 0) + return sz; + spec->offset = access_idx * sz; + + for (i = 1; i < spec->raw_len; i++) { + t = skip_mods_and_typedefs(btf, id, &id); + if (!t) + return -EINVAL; + + access_idx = spec->raw_spec[i]; + + if (btf_is_composite(t)) { + const struct btf_member *m; + __u32 offset; + + if (access_idx >= btf_vlen(t)) + return -EINVAL; + if (btf_member_bitfield_size(t, access_idx)) + return -EINVAL; + + offset = btf_member_bit_offset(t, access_idx); + if (offset % 8) + return -EINVAL; + spec->offset += offset / 8; + + m = btf_members(t) + access_idx; + if (m->name_off) { + name = btf__name_by_offset(btf, m->name_off); + if (str_is_empty(name)) + return -EINVAL; + + spec->spec[spec->len].type_id = id; + spec->spec[spec->len].idx = access_idx; + spec->spec[spec->len].name = name; + spec->len++; + } + + id = m->type; + } else if (btf_is_array(t)) { + const struct btf_array *a = btf_array(t); + + t = skip_mods_and_typedefs(btf, a->type, &id); + if (!t || access_idx >= a->nelems) + return -EINVAL; + + spec->spec[spec->len].type_id = id; + spec->spec[spec->len].idx = access_idx; + spec->len++; + + sz = btf__resolve_size(btf, id); + if (sz < 0) + return sz; + spec->offset += access_idx * sz; + } else { + pr_warning("relo for [%u] %s (at idx %d) captures type [%d] of unexpected kind %d\n", + type_id, spec_str, i, id, btf_kind(t)); + return -EINVAL; + } + } + + return 0; +} + +static bool bpf_core_is_flavor_sep(const char *s) +{ + /* check X___Y name pattern, where X and Y are not underscores */ + return s[0] != '_' && /* X */ + s[1] == '_' && s[2] == '_' && s[3] == '_' && /* ___ */ + s[4] != '_'; /* Y */ +} + +/* Given 'some_struct_name___with_flavor' return the length of a name prefix + * before last triple underscore. Struct name part after last triple + * underscore is ignored by BPF CO-RE relocation during relocation matching. + */ +static size_t bpf_core_essential_name_len(const char *name) +{ + size_t n = strlen(name); + int i; + + for (i = n - 5; i >= 0; i--) { + if (bpf_core_is_flavor_sep(name + i)) + return i + 1; + } + return n; +} + +/* dynamically sized list of type IDs */ +struct ids_vec { + __u32 *data; + int len; +}; + +static void bpf_core_free_cands(struct ids_vec *cand_ids) +{ + free(cand_ids->data); + free(cand_ids); +} + +static struct ids_vec *bpf_core_find_cands(const struct btf *local_btf, + __u32 local_type_id, + const struct btf *targ_btf) +{ + size_t local_essent_len, targ_essent_len; + const char *local_name, *targ_name; + const struct btf_type *t; + struct ids_vec *cand_ids; + __u32 *new_ids; + int i, err, n; + + t = btf__type_by_id(local_btf, local_type_id); + if (!t) + return ERR_PTR(-EINVAL); + + local_name = btf__name_by_offset(local_btf, t->name_off); + if (str_is_empty(local_name)) + return ERR_PTR(-EINVAL); + local_essent_len = bpf_core_essential_name_len(local_name); + + cand_ids = calloc(1, sizeof(*cand_ids)); + if (!cand_ids) + return ERR_PTR(-ENOMEM); + + n = btf__get_nr_types(targ_btf); + for (i = 1; i <= n; i++) { + t = btf__type_by_id(targ_btf, i); + targ_name = btf__name_by_offset(targ_btf, t->name_off); + if (str_is_empty(targ_name)) + continue; + + targ_essent_len = bpf_core_essential_name_len(targ_name); + if (targ_essent_len != local_essent_len) + continue; + + if (strncmp(local_name, targ_name, local_essent_len) == 0) { + pr_debug("[%d] %s: found candidate [%d] %s\n", + local_type_id, local_name, i, targ_name); + new_ids = realloc(cand_ids->data, cand_ids->len + 1); + if (!new_ids) { + err = -ENOMEM; + goto err_out; + } + cand_ids->data = new_ids; + cand_ids->data[cand_ids->len++] = i; + } + } + return cand_ids; +err_out: + bpf_core_free_cands(cand_ids); + return ERR_PTR(err); +} + +/* Check two types for compatibility, skipping const/volatile/restrict and + * typedefs, to ensure we are relocating offset to the compatible entities: + * - any two STRUCTs/UNIONs are compatible and can be mixed; + * - any two FWDs are compatible; + * - any two PTRs are always compatible; + * - for ENUMs, check sizes, names are ignored; + * - for INT, size and bitness should match, signedness is ignored; + * - for ARRAY, dimensionality is ignored, element types are checked for + * compatibility recursively; + * - everything else shouldn't be ever a target of relocation. + * These rules are not set in stone and probably will be adjusted as we get + * more experience with using BPF CO-RE relocations. + */ +static int bpf_core_fields_are_compat(const struct btf *local_btf, + __u32 local_id, + const struct btf *targ_btf, + __u32 targ_id) +{ + const struct btf_type *local_type, *targ_type; + +recur: + local_type = skip_mods_and_typedefs(local_btf, local_id, &local_id); + targ_type = skip_mods_and_typedefs(targ_btf, targ_id, &targ_id); + if (!local_type || !targ_type) + return -EINVAL; + + if (btf_is_composite(local_type) && btf_is_composite(targ_type)) + return 1; + if (btf_kind(local_type) != btf_kind(targ_type)) + return 0; + + switch (btf_kind(local_type)) { + case BTF_KIND_FWD: + case BTF_KIND_PTR: + return 1; + case BTF_KIND_ENUM: + return local_type->size == targ_type->size; + case BTF_KIND_INT: + return btf_int_offset(local_type) == 0 && + btf_int_offset(targ_type) == 0 && + local_type->size == targ_type->size && + btf_int_bits(local_type) == btf_int_bits(targ_type); + case BTF_KIND_ARRAY: + local_id = btf_array(local_type)->type; + targ_id = btf_array(targ_type)->type; + goto recur; + default: + pr_warning("unexpected kind %d relocated, local [%d], target [%d]\n", + btf_kind(local_type), local_id, targ_id); + return 0; + } +} + +/* + * Given single high-level named field accessor in local type, find + * corresponding high-level accessor for a target type. Along the way, + * maintain low-level spec for target as well. Also keep updating target + * offset. + * + * Searching is performed through recursive exhaustive enumeration of all + * fields of a struct/union. If there are any anonymous (embedded) + * structs/unions, they are recursively searched as well. If field with + * desired name is found, check compatibility between local and target types, + * before returning result. + * + * 1 is returned, if field is found. + * 0 is returned if no compatible field is found. + * <0 is returned on error. + */ +static int bpf_core_match_member(const struct btf *local_btf, + const struct bpf_core_accessor *local_acc, + const struct btf *targ_btf, + __u32 targ_id, + struct bpf_core_spec *spec, + __u32 *next_targ_id) +{ + const struct btf_type *local_type, *targ_type; + const struct btf_member *local_member, *m; + const char *local_name, *targ_name; + __u32 local_id; + int i, n, found; + + targ_type = skip_mods_and_typedefs(targ_btf, targ_id, &targ_id); + if (!targ_type) + return -EINVAL; + if (!btf_is_composite(targ_type)) + return 0; + + local_id = local_acc->type_id; + local_type = btf__type_by_id(local_btf, local_id); + local_member = btf_members(local_type) + local_acc->idx; + local_name = btf__name_by_offset(local_btf, local_member->name_off); + + n = btf_vlen(targ_type); + m = btf_members(targ_type); + for (i = 0; i < n; i++, m++) { + __u32 offset; + + /* bitfield relocations not supported */ + if (btf_member_bitfield_size(targ_type, i)) + continue; + offset = btf_member_bit_offset(targ_type, i); + if (offset % 8) + continue; + + /* too deep struct/union/array nesting */ + if (spec->raw_len == BPF_CORE_SPEC_MAX_LEN) + return -E2BIG; + + /* speculate this member will be the good one */ + spec->offset += offset / 8; + spec->raw_spec[spec->raw_len++] = i; + + targ_name = btf__name_by_offset(targ_btf, m->name_off); + if (str_is_empty(targ_name)) { + /* embedded struct/union, we need to go deeper */ + found = bpf_core_match_member(local_btf, local_acc, + targ_btf, m->type, + spec, next_targ_id); + if (found) /* either found or error */ + return found; + } else if (strcmp(local_name, targ_name) == 0) { + /* matching named field */ + struct bpf_core_accessor *targ_acc; + + targ_acc = &spec->spec[spec->len++]; + targ_acc->type_id = targ_id; + targ_acc->idx = i; + targ_acc->name = targ_name; + + *next_targ_id = m->type; + found = bpf_core_fields_are_compat(local_btf, + local_member->type, + targ_btf, m->type); + if (!found) + spec->len--; /* pop accessor */ + return found; + } + /* member turned out not to be what we looked for */ + spec->offset -= offset / 8; + spec->raw_len--; + } + + return 0; +} + +/* + * Try to match local spec to a target type and, if successful, produce full + * target spec (high-level, low-level + offset). + */ +static int bpf_core_spec_match(struct bpf_core_spec *local_spec, + const struct btf *targ_btf, __u32 targ_id, + struct bpf_core_spec *targ_spec) +{ + const struct btf_type *targ_type; + const struct bpf_core_accessor *local_acc; + struct bpf_core_accessor *targ_acc; + int i, sz, matched; + + memset(targ_spec, 0, sizeof(*targ_spec)); + targ_spec->btf = targ_btf; + + local_acc = &local_spec->spec[0]; + targ_acc = &targ_spec->spec[0]; + + for (i = 0; i < local_spec->len; i++, local_acc++, targ_acc++) { + targ_type = skip_mods_and_typedefs(targ_spec->btf, targ_id, + &targ_id); + if (!targ_type) + return -EINVAL; + + if (local_acc->name) { + matched = bpf_core_match_member(local_spec->btf, + local_acc, + targ_btf, targ_id, + targ_spec, &targ_id); + if (matched <= 0) + return matched; + } else { + /* for i=0, targ_id is already treated as array element + * type (because it's the original struct), for others + * we should find array element type first + */ + if (i > 0) { + const struct btf_array *a; + + if (!btf_is_array(targ_type)) + return 0; + + a = btf_array(targ_type); + if (local_acc->idx >= a->nelems) + return 0; + if (!skip_mods_and_typedefs(targ_btf, a->type, + &targ_id)) + return -EINVAL; + } + + /* too deep struct/union/array nesting */ + if (targ_spec->raw_len == BPF_CORE_SPEC_MAX_LEN) + return -E2BIG; + + targ_acc->type_id = targ_id; + targ_acc->idx = local_acc->idx; + targ_acc->name = NULL; + targ_spec->len++; + targ_spec->raw_spec[targ_spec->raw_len] = targ_acc->idx; + targ_spec->raw_len++; + + sz = btf__resolve_size(targ_btf, targ_id); + if (sz < 0) + return sz; + targ_spec->offset += local_acc->idx * sz; + } + } + + return 1; +} + +/* + * Patch relocatable BPF instruction. + * Expected insn->imm value is provided for validation, as well as the new + * relocated value. + * + * Currently three kinds of BPF instructions are supported: + * 1. rX = <imm> (assignment with immediate operand); + * 2. rX += <imm> (arithmetic operations with immediate operand); + * 3. *(rX) = <imm> (indirect memory assignment with immediate operand). + * + * If actual insn->imm value is wrong, bail out. + */ +static int bpf_core_reloc_insn(struct bpf_program *prog, int insn_off, + __u32 orig_off, __u32 new_off) +{ + struct bpf_insn *insn; + int insn_idx; + __u8 class; + + if (insn_off % sizeof(struct bpf_insn)) + return -EINVAL; + insn_idx = insn_off / sizeof(struct bpf_insn); + + insn = &prog->insns[insn_idx]; + class = BPF_CLASS(insn->code); + + if (class == BPF_ALU || class == BPF_ALU64) { + if (BPF_SRC(insn->code) != BPF_K) + return -EINVAL; + if (insn->imm != orig_off) + return -EINVAL; + insn->imm = new_off; + pr_debug("prog '%s': patched insn #%d (ALU/ALU64) imm %d -> %d\n", + bpf_program__title(prog, false), + insn_idx, orig_off, new_off); + } else { + pr_warning("prog '%s': trying to relocate unrecognized insn #%d, code:%x, src:%x, dst:%x, off:%x, imm:%x\n", + bpf_program__title(prog, false), + insn_idx, insn->code, insn->src_reg, insn->dst_reg, + insn->off, insn->imm); + return -EINVAL; + } + return 0; +} + +/* + * Probe few well-known locations for vmlinux kernel image and try to load BTF + * data out of it to use for target BTF. + */ +static struct btf *bpf_core_find_kernel_btf(void) +{ + const char *locations[] = { + "/lib/modules/%1$s/vmlinux-%1$s", + "/usr/lib/modules/%1$s/kernel/vmlinux", + }; + char path[PATH_MAX + 1]; + struct utsname buf; + struct btf *btf; + int i; + + uname(&buf); + + for (i = 0; i < ARRAY_SIZE(locations); i++) { + snprintf(path, PATH_MAX, locations[i], buf.release); + + if (access(path, R_OK)) + continue; + + btf = btf__parse_elf(path, NULL); + pr_debug("kernel BTF load from '%s': %ld\n", + path, PTR_ERR(btf)); + if (IS_ERR(btf)) + continue; + + return btf; + } + + pr_warning("failed to find valid kernel BTF\n"); + return ERR_PTR(-ESRCH); +} + +/* Output spec definition in the format: + * [<type-id>] (<type-name>) + <raw-spec> => <offset>@<spec>, + * where <spec> is a C-syntax view of recorded field access, e.g.: x.a[3].b + */ +static void bpf_core_dump_spec(int level, const struct bpf_core_spec *spec) +{ + const struct btf_type *t; + const char *s; + __u32 type_id; + int i; + + type_id = spec->spec[0].type_id; + t = btf__type_by_id(spec->btf, type_id); + s = btf__name_by_offset(spec->btf, t->name_off); + libbpf_print(level, "[%u] %s + ", type_id, s); + + for (i = 0; i < spec->raw_len; i++) + libbpf_print(level, "%d%s", spec->raw_spec[i], + i == spec->raw_len - 1 ? " => " : ":"); + + libbpf_print(level, "%u @ &x", spec->offset); + + for (i = 0; i < spec->len; i++) { + if (spec->spec[i].name) + libbpf_print(level, ".%s", spec->spec[i].name); + else + libbpf_print(level, "[%u]", spec->spec[i].idx); + } + +} + +static size_t bpf_core_hash_fn(const void *key, void *ctx) +{ + return (size_t)key; +} + +static bool bpf_core_equal_fn(const void *k1, const void *k2, void *ctx) +{ + return k1 == k2; +} + +static void *u32_as_hash_key(__u32 x) +{ + return (void *)(uintptr_t)x; +} + +/* + * CO-RE relocate single instruction. + * + * The outline and important points of the algorithm: + * 1. For given local type, find corresponding candidate target types. + * Candidate type is a type with the same "essential" name, ignoring + * everything after last triple underscore (___). E.g., `sample`, + * `sample___flavor_one`, `sample___flavor_another_one`, are all candidates + * for each other. Names with triple underscore are referred to as + * "flavors" and are useful, among other things, to allow to + * specify/support incompatible variations of the same kernel struct, which + * might differ between different kernel versions and/or build + * configurations. + * + * N.B. Struct "flavors" could be generated by bpftool's BTF-to-C + * converter, when deduplicated BTF of a kernel still contains more than + * one different types with the same name. In that case, ___2, ___3, etc + * are appended starting from second name conflict. But start flavors are + * also useful to be defined "locally", in BPF program, to extract same + * data from incompatible changes between different kernel + * versions/configurations. For instance, to handle field renames between + * kernel versions, one can use two flavors of the struct name with the + * same common name and use conditional relocations to extract that field, + * depending on target kernel version. + * 2. For each candidate type, try to match local specification to this + * candidate target type. Matching involves finding corresponding + * high-level spec accessors, meaning that all named fields should match, + * as well as all array accesses should be within the actual bounds. Also, + * types should be compatible (see bpf_core_fields_are_compat for details). + * 3. It is supported and expected that there might be multiple flavors + * matching the spec. As long as all the specs resolve to the same set of + * offsets across all candidates, there is not error. If there is any + * ambiguity, CO-RE relocation will fail. This is necessary to accomodate + * imprefection of BTF deduplication, which can cause slight duplication of + * the same BTF type, if some directly or indirectly referenced (by + * pointer) type gets resolved to different actual types in different + * object files. If such situation occurs, deduplicated BTF will end up + * with two (or more) structurally identical types, which differ only in + * types they refer to through pointer. This should be OK in most cases and + * is not an error. + * 4. Candidate types search is performed by linearly scanning through all + * types in target BTF. It is anticipated that this is overall more + * efficient memory-wise and not significantly worse (if not better) + * CPU-wise compared to prebuilding a map from all local type names to + * a list of candidate type names. It's also sped up by caching resolved + * list of matching candidates per each local "root" type ID, that has at + * least one bpf_offset_reloc associated with it. This list is shared + * between multiple relocations for the same type ID and is updated as some + * of the candidates are pruned due to structural incompatibility. + */ +static int bpf_core_reloc_offset(struct bpf_program *prog, + const struct bpf_offset_reloc *relo, + int relo_idx, + const struct btf *local_btf, + const struct btf *targ_btf, + struct hashmap *cand_cache) +{ + const char *prog_name = bpf_program__title(prog, false); + struct bpf_core_spec local_spec, cand_spec, targ_spec; + const void *type_key = u32_as_hash_key(relo->type_id); + const struct btf_type *local_type, *cand_type; + const char *local_name, *cand_name; + struct ids_vec *cand_ids; + __u32 local_id, cand_id; + const char *spec_str; + int i, j, err; + + local_id = relo->type_id; + local_type = btf__type_by_id(local_btf, local_id); + if (!local_type) + return -EINVAL; + + local_name = btf__name_by_offset(local_btf, local_type->name_off); + if (str_is_empty(local_name)) + return -EINVAL; + + spec_str = btf__name_by_offset(local_btf, relo->access_str_off); + if (str_is_empty(spec_str)) + return -EINVAL; + + err = bpf_core_spec_parse(local_btf, local_id, spec_str, &local_spec); + if (err) { + pr_warning("prog '%s': relo #%d: parsing [%d] %s + %s failed: %d\n", + prog_name, relo_idx, local_id, local_name, spec_str, + err); + return -EINVAL; + } + + pr_debug("prog '%s': relo #%d: spec is ", prog_name, relo_idx); + bpf_core_dump_spec(LIBBPF_DEBUG, &local_spec); + libbpf_print(LIBBPF_DEBUG, "\n"); + + if (!hashmap__find(cand_cache, type_key, (void **)&cand_ids)) { + cand_ids = bpf_core_find_cands(local_btf, local_id, targ_btf); + if (IS_ERR(cand_ids)) { + pr_warning("prog '%s': relo #%d: target candidate search failed for [%d] %s: %ld", + prog_name, relo_idx, local_id, local_name, + PTR_ERR(cand_ids)); + return PTR_ERR(cand_ids); + } + err = hashmap__set(cand_cache, type_key, cand_ids, NULL, NULL); + if (err) { + bpf_core_free_cands(cand_ids); + return err; + } + } + + for (i = 0, j = 0; i < cand_ids->len; i++) { + cand_id = cand_ids->data[i]; + cand_type = btf__type_by_id(targ_btf, cand_id); + cand_name = btf__name_by_offset(targ_btf, cand_type->name_off); + + err = bpf_core_spec_match(&local_spec, targ_btf, + cand_id, &cand_spec); + pr_debug("prog '%s': relo #%d: matching candidate #%d %s against spec ", + prog_name, relo_idx, i, cand_name); + bpf_core_dump_spec(LIBBPF_DEBUG, &cand_spec); + libbpf_print(LIBBPF_DEBUG, ": %d\n", err); + if (err < 0) { + pr_warning("prog '%s': relo #%d: matching error: %d\n", + prog_name, relo_idx, err); + return err; + } + if (err == 0) + continue; + + if (j == 0) { + targ_spec = cand_spec; + } else if (cand_spec.offset != targ_spec.offset) { + /* if there are many candidates, they should all + * resolve to the same offset + */ + pr_warning("prog '%s': relo #%d: offset ambiguity: %u != %u\n", + prog_name, relo_idx, cand_spec.offset, + targ_spec.offset); + return -EINVAL; + } + + cand_ids->data[j++] = cand_spec.spec[0].type_id; + } + + cand_ids->len = j; + if (cand_ids->len == 0) { + pr_warning("prog '%s': relo #%d: no matching targets found for [%d] %s + %s\n", + prog_name, relo_idx, local_id, local_name, spec_str); + return -ESRCH; + } + + err = bpf_core_reloc_insn(prog, relo->insn_off, + local_spec.offset, targ_spec.offset); + if (err) { + pr_warning("prog '%s': relo #%d: failed to patch insn at offset %d: %d\n", + prog_name, relo_idx, relo->insn_off, err); + return -EINVAL; + } + + return 0; +} + +static int +bpf_core_reloc_offsets(struct bpf_object *obj, const char *targ_btf_path) +{ + const struct btf_ext_info_sec *sec; + const struct bpf_offset_reloc *rec; + const struct btf_ext_info *seg; + struct hashmap_entry *entry; + struct hashmap *cand_cache = NULL; + struct bpf_program *prog; + struct btf *targ_btf; + const char *sec_name; + int i, err = 0; + + if (targ_btf_path) + targ_btf = btf__parse_elf(targ_btf_path, NULL); + else + targ_btf = bpf_core_find_kernel_btf(); + if (IS_ERR(targ_btf)) { + pr_warning("failed to get target BTF: %ld\n", + PTR_ERR(targ_btf)); + return PTR_ERR(targ_btf); + } + + cand_cache = hashmap__new(bpf_core_hash_fn, bpf_core_equal_fn, NULL); + if (IS_ERR(cand_cache)) { + err = PTR_ERR(cand_cache); + goto out; + } + + seg = &obj->btf_ext->offset_reloc_info; + for_each_btf_ext_sec(seg, sec) { + sec_name = btf__name_by_offset(obj->btf, sec->sec_name_off); + if (str_is_empty(sec_name)) { + err = -EINVAL; + goto out; + } + prog = bpf_object__find_program_by_title(obj, sec_name); + if (!prog) { + pr_warning("failed to find program '%s' for CO-RE offset relocation\n", + sec_name); + err = -EINVAL; + goto out; + } + + pr_debug("prog '%s': performing %d CO-RE offset relocs\n", + sec_name, sec->num_info); + + for_each_btf_ext_rec(seg, sec, i, rec) { + err = bpf_core_reloc_offset(prog, rec, i, obj->btf, + targ_btf, cand_cache); + if (err) { + pr_warning("prog '%s': relo #%d: failed to relocate: %d\n", + sec_name, i, err); + goto out; + } + } + } + +out: + btf__free(targ_btf); + if (!IS_ERR_OR_NULL(cand_cache)) { + hashmap__for_each_entry(cand_cache, entry, i) { + bpf_core_free_cands(entry->value); + } + hashmap__free(cand_cache); + } + return err; +} + +static int +bpf_object__relocate_core(struct bpf_object *obj, const char *targ_btf_path) +{ + int err = 0; + + if (obj->btf_ext->offset_reloc_info.len) + err = bpf_core_reloc_offsets(obj, targ_btf_path); + + return err; +} + static int bpf_program__reloc_text(struct bpf_program *prog, struct bpf_object *obj, struct reloc_desc *relo) @@ -2399,14 +3235,21 @@ bpf_program__relocate(struct bpf_program *prog, struct bpf_object *obj) return 0; } - static int -bpf_object__relocate(struct bpf_object *obj) +bpf_object__relocate(struct bpf_object *obj, const char *targ_btf_path) { struct bpf_program *prog; size_t i; int err; + if (obj->btf_ext) { + err = bpf_object__relocate_core(obj, targ_btf_path); + if (err) { + pr_warning("failed to perform CO-RE relocations: %d\n", + err); + return err; + } + } for (i = 0; i < obj->nr_programs; i++) { prog = &obj->programs[i]; @@ -2807,7 +3650,7 @@ int bpf_object__load_xattr(struct bpf_object_load_attr *attr) obj->loaded = true; CHECK_ERR(bpf_object__create_maps(obj), err, out); - CHECK_ERR(bpf_object__relocate(obj), err, out); + CHECK_ERR(bpf_object__relocate(obj, attr->target_btf_path), err, out); CHECK_ERR(bpf_object__load_progs(obj, attr->log_level), err, out); return 0; diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 8a9d462a6f6d..e8f70977d137 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -92,6 +92,7 @@ LIBBPF_API void bpf_object__close(struct bpf_object *object); struct bpf_object_load_attr { struct bpf_object *obj; int log_level; + const char *target_btf_path; }; /* Load/unload object into/from kernel */ diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h index 2ac29bd36226..2e83a34f8c79 100644 --- a/tools/lib/bpf/libbpf_internal.h +++ b/tools/lib/bpf/libbpf_internal.h @@ -29,6 +29,10 @@ #ifndef max # define max(x, y) ((x) < (y) ? (y) : (x)) #endif +#ifndef offsetofend +# define offsetofend(TYPE, FIELD) \ + (offsetof(TYPE, FIELD) + sizeof(((TYPE *)0)->FIELD)) +#endif extern void libbpf_print(enum libbpf_print_level level, const char *format, ...) @@ -46,4 +50,105 @@ do { \ int libbpf__load_raw_btf(const char *raw_types, size_t types_len, const char *str_sec, size_t str_len); +struct btf_ext_info { + /* + * info points to the individual info section (e.g. func_info and + * line_info) from the .BTF.ext. It does not include the __u32 rec_size. + */ + void *info; + __u32 rec_size; + __u32 len; +}; + +#define for_each_btf_ext_sec(seg, sec) \ + for (sec = (seg)->info; \ + (void *)sec < (seg)->info + (seg)->len; \ + sec = (void *)sec + sizeof(struct btf_ext_info_sec) + \ + (seg)->rec_size * sec->num_info) + +#define for_each_btf_ext_rec(seg, sec, i, rec) \ + for (i = 0, rec = (void *)&(sec)->data; \ + i < (sec)->num_info; \ + i++, rec = (void *)rec + (seg)->rec_size) + +struct btf_ext { + union { + struct btf_ext_header *hdr; + void *data; + }; + struct btf_ext_info func_info; + struct btf_ext_info line_info; + struct btf_ext_info offset_reloc_info; + __u32 data_size; +}; + +struct btf_ext_info_sec { + __u32 sec_name_off; + __u32 num_info; + /* Followed by num_info * record_size number of bytes */ + __u8 data[0]; +}; + +/* The minimum bpf_func_info checked by the loader */ +struct bpf_func_info_min { + __u32 insn_off; + __u32 type_id; +}; + +/* The minimum bpf_line_info checked by the loader */ +struct bpf_line_info_min { + __u32 insn_off; + __u32 file_name_off; + __u32 line_off; + __u32 line_col; +}; + +/* The minimum bpf_offset_reloc checked by the loader + * + * Offset relocation captures the following data: + * - insn_off - instruction offset (in bytes) within a BPF program that needs + * its insn->imm field to be relocated with actual offset; + * - type_id - BTF type ID of the "root" (containing) entity of a relocatable + * offset; + * - access_str_off - offset into corresponding .BTF string section. String + * itself encodes an accessed field using a sequence of field and array + * indicies, separated by colon (:). It's conceptually very close to LLVM's + * getelementptr ([0]) instruction's arguments for identifying offset to + * a field. + * + * Example to provide a better feel. + * + * struct sample { + * int a; + * struct { + * int b[10]; + * }; + * }; + * + * struct sample *s = ...; + * int x = &s->a; // encoded as "0:0" (a is field #0) + * int y = &s->b[5]; // encoded as "0:1:0:5" (anon struct is field #1, + * // b is field #0 inside anon struct, accessing elem #5) + * int z = &s[10]->b; // encoded as "10:1" (ptr is used as an array) + * + * type_id for all relocs in this example will capture BTF type id of + * `struct sample`. + * + * Such relocation is emitted when using __builtin_preserve_access_index() + * Clang built-in, passing expression that captures field address, e.g.: + * + * bpf_probe_read(&dst, sizeof(dst), + * __builtin_preserve_access_index(&src->a.b.c)); + * + * In this case Clang will emit offset relocation recording necessary data to + * be able to find offset of embedded `a.b.c` field within `src` struct. + * + * [0] https://llvm.org/docs/LangRef.html#getelementptr-instruction + */ +struct bpf_offset_reloc { + __u32 insn_off; + __u32 type_id; + __u32 access_str_off; +}; + #endif /* __LIBBPF_LIBBPF_INTERNAL_H */ diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h index 120aa86c58d3..8b503ea142f0 100644 --- a/tools/testing/selftests/bpf/bpf_helpers.h +++ b/tools/testing/selftests/bpf/bpf_helpers.h @@ -504,4 +504,24 @@ struct pt_regs; (void *)(PT_REGS_FP(ctx) + sizeof(ip))); }) #endif +/* + * BPF_CORE_READ abstracts away bpf_probe_read() call and captures offset + * relocation for source address using __builtin_preserve_access_index() + * built-in, provided by Clang. + * + * __builtin_preserve_access_index() takes as an argument an expression of + * taking an address of a field within struct/union. It makes compiler emit + * a relocation, which records BTF type ID describing root struct/union and an + * accessor string which describes exact embedded field that was used to take + * an address. See detailed description of this relocation format and + * semantics in comments to struct bpf_offset_reloc in libbpf_internal.h. + * + * This relocation allows libbpf to adjust BPF instruction to use correct + * actual field offset, based on target kernel BTF type that matches original + * (local) BTF, used to record relocation. + */ +#define BPF_CORE_READ(dst, src) \ + bpf_probe_read((dst), sizeof(*(src)), \ + __builtin_preserve_access_index(src)) + #endif diff --git a/tools/testing/selftests/bpf/prog_tests/core_reloc.c b/tools/testing/selftests/bpf/prog_tests/core_reloc.c new file mode 100644 index 000000000000..f3863f976a48 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/core_reloc.c @@ -0,0 +1,385 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <test_progs.h> +#include "progs/core_reloc_types.h" + +#define STRUCT_TO_CHAR_PTR(struct_name) (const char *)&(struct struct_name) + +#define FLAVORS_DATA(struct_name) STRUCT_TO_CHAR_PTR(struct_name) { \ + .a = 42, \ + .b = 0xc001, \ + .c = 0xbeef, \ +} + +#define FLAVORS_CASE_COMMON(name) \ + .case_name = #name, \ + .bpf_obj_file = "test_core_reloc_flavors.o", \ + .btf_src_file = "btf__core_reloc_" #name ".o" \ + +#define FLAVORS_CASE(name) { \ + FLAVORS_CASE_COMMON(name), \ + .input = FLAVORS_DATA(core_reloc_##name), \ + .input_len = sizeof(struct core_reloc_##name), \ + .output = FLAVORS_DATA(core_reloc_flavors), \ + .output_len = sizeof(struct core_reloc_flavors), \ +} + +#define FLAVORS_ERR_CASE(name) { \ + FLAVORS_CASE_COMMON(name), \ + .fails = true, \ +} + +#define NESTING_DATA(struct_name) STRUCT_TO_CHAR_PTR(struct_name) { \ + .a = { .a = { .a = 42 } }, \ + .b = { .b = { .b = 0xc001 } }, \ +} + +#define NESTING_CASE_COMMON(name) \ + .case_name = #name, \ + .bpf_obj_file = "test_core_reloc_nesting.o", \ + .btf_src_file = "btf__core_reloc_" #name ".o" + +#define NESTING_CASE(name) { \ + NESTING_CASE_COMMON(name), \ + .input = NESTING_DATA(core_reloc_##name), \ + .input_len = sizeof(struct core_reloc_##name), \ + .output = NESTING_DATA(core_reloc_nesting), \ + .output_len = sizeof(struct core_reloc_nesting) \ +} + +#define NESTING_ERR_CASE(name) { \ + NESTING_CASE_COMMON(name), \ + .fails = true, \ +} + +#define ARRAYS_DATA(struct_name) STRUCT_TO_CHAR_PTR(struct_name) { \ + .a = { [2] = 1 }, \ + .b = { [1] = { [2] = { [3] = 2 } } }, \ + .c = { [1] = { .c = 3 } }, \ + .d = { [0] = { [0] = { .d = 4 } } }, \ +} + +#define ARRAYS_CASE_COMMON(name) \ + .case_name = #name, \ + .bpf_obj_file = "test_core_reloc_arrays.o", \ + .btf_src_file = "btf__core_reloc_" #name ".o" + +#define ARRAYS_CASE(name) { \ + ARRAYS_CASE_COMMON(name), \ + .input = ARRAYS_DATA(core_reloc_##name), \ + .input_len = sizeof(struct core_reloc_##name), \ + .output = STRUCT_TO_CHAR_PTR(core_reloc_arrays_output) { \ + .a2 = 1, \ + .b123 = 2, \ + .c1c = 3, \ + .d00d = 4, \ + }, \ + .output_len = sizeof(struct core_reloc_arrays_output) \ +} + +#define ARRAYS_ERR_CASE(name) { \ + ARRAYS_CASE_COMMON(name), \ + .fails = true, \ +} + +#define PRIMITIVES_DATA(struct_name) STRUCT_TO_CHAR_PTR(struct_name) { \ + .a = 1, \ + .b = 2, \ + .c = 3, \ + .d = (void *)4, \ + .f = (void *)5, \ +} + +#define PRIMITIVES_CASE_COMMON(name) \ + .case_name = #name, \ + .bpf_obj_file = "test_core_reloc_primitives.o", \ + .btf_src_file = "btf__core_reloc_" #name ".o" + +#define PRIMITIVES_CASE(name) { \ + PRIMITIVES_CASE_COMMON(name), \ + .input = PRIMITIVES_DATA(core_reloc_##name), \ + .input_len = sizeof(struct core_reloc_##name), \ + .output = PRIMITIVES_DATA(core_reloc_primitives), \ + .output_len = sizeof(struct core_reloc_primitives), \ +} + +#define PRIMITIVES_ERR_CASE(name) { \ + PRIMITIVES_CASE_COMMON(name), \ + .fails = true, \ +} + +#define MODS_CASE(name) { \ + .case_name = #name, \ + .bpf_obj_file = "test_core_reloc_mods.o", \ + .btf_src_file = "btf__core_reloc_" #name ".o", \ + .input = STRUCT_TO_CHAR_PTR(core_reloc_##name) { \ + .a = 1, \ + .b = 2, \ + .c = (void *)3, \ + .d = (void *)4, \ + .e = { [2] = 5 }, \ + .f = { [1] = 6 }, \ + .g = { .x = 7 }, \ + .h = { .y = 8 }, \ + }, \ + .input_len = sizeof(struct core_reloc_##name), \ + .output = STRUCT_TO_CHAR_PTR(core_reloc_mods_output) { \ + .a = 1, .b = 2, .c = 3, .d = 4, \ + .e = 5, .f = 6, .g = 7, .h = 8, \ + }, \ + .output_len = sizeof(struct core_reloc_mods_output), \ +} + +#define PTR_AS_ARR_CASE(name) { \ + .case_name = #name, \ + .bpf_obj_file = "test_core_reloc_ptr_as_arr.o", \ + .btf_src_file = "btf__core_reloc_" #name ".o", \ + .input = (const char *)&(struct core_reloc_##name []){ \ + { .a = 1 }, \ + { .a = 2 }, \ + { .a = 3 }, \ + }, \ + .input_len = 3 * sizeof(struct core_reloc_##name), \ + .output = STRUCT_TO_CHAR_PTR(core_reloc_ptr_as_arr) { \ + .a = 3, \ + }, \ + .output_len = sizeof(struct core_reloc_ptr_as_arr), \ +} + +#define INTS_DATA(struct_name) STRUCT_TO_CHAR_PTR(struct_name) { \ + .u8_field = 1, \ + .s8_field = 2, \ + .u16_field = 3, \ + .s16_field = 4, \ + .u32_field = 5, \ + .s32_field = 6, \ + .u64_field = 7, \ + .s64_field = 8, \ +} + +#define INTS_CASE_COMMON(name) \ + .case_name = #name, \ + .bpf_obj_file = "test_core_reloc_ints.o", \ + .btf_src_file = "btf__core_reloc_" #name ".o" + +#define INTS_CASE(name) { \ + INTS_CASE_COMMON(name), \ + .input = INTS_DATA(core_reloc_##name), \ + .input_len = sizeof(struct core_reloc_##name), \ + .output = INTS_DATA(core_reloc_ints), \ + .output_len = sizeof(struct core_reloc_ints), \ +} + +#define INTS_ERR_CASE(name) { \ + INTS_CASE_COMMON(name), \ + .fails = true, \ +} + +struct core_reloc_test_case { + const char *case_name; + const char *bpf_obj_file; + const char *btf_src_file; + const char *input; + int input_len; + const char *output; + int output_len; + bool fails; +}; + +static struct core_reloc_test_case test_cases[] = { + /* validate we can find kernel image and use its BTF for relocs */ + { + .case_name = "kernel", + .bpf_obj_file = "test_core_reloc_kernel.o", + .btf_src_file = NULL, /* load from /lib/modules/$(uname -r) */ + .input = "", + .input_len = 0, + .output = "\1", /* true */ + .output_len = 1, + }, + + /* validate BPF program can use multiple flavors to match against + * single target BTF type + */ + FLAVORS_CASE(flavors), + + FLAVORS_ERR_CASE(flavors__err_wrong_name), + + /* various struct/enum nesting and resolution scenarios */ + NESTING_CASE(nesting), + NESTING_CASE(nesting___anon_embed), + NESTING_CASE(nesting___struct_union_mixup), + NESTING_CASE(nesting___extra_nesting), + NESTING_CASE(nesting___dup_compat_types), + + NESTING_ERR_CASE(nesting___err_missing_field), + NESTING_ERR_CASE(nesting___err_array_field), + NESTING_ERR_CASE(nesting___err_missing_container), + NESTING_ERR_CASE(nesting___err_nonstruct_container), + NESTING_ERR_CASE(nesting___err_array_container), + NESTING_ERR_CASE(nesting___err_dup_incompat_types), + NESTING_ERR_CASE(nesting___err_partial_match_dups), + NESTING_ERR_CASE(nesting___err_too_deep), + + /* various array access relocation scenarios */ + ARRAYS_CASE(arrays), + ARRAYS_CASE(arrays___diff_arr_dim), + ARRAYS_CASE(arrays___diff_arr_val_sz), + + ARRAYS_ERR_CASE(arrays___err_too_small), + ARRAYS_ERR_CASE(arrays___err_too_shallow), + ARRAYS_ERR_CASE(arrays___err_non_array), + ARRAYS_ERR_CASE(arrays___err_wrong_val_type1), + ARRAYS_ERR_CASE(arrays___err_wrong_val_type2), + + /* enum/ptr/int handling scenarios */ + PRIMITIVES_CASE(primitives), + PRIMITIVES_CASE(primitives___diff_enum_def), + PRIMITIVES_CASE(primitives___diff_func_proto), + PRIMITIVES_CASE(primitives___diff_ptr_type), + + PRIMITIVES_ERR_CASE(primitives___err_non_enum), + PRIMITIVES_ERR_CASE(primitives___err_non_int), + PRIMITIVES_ERR_CASE(primitives___err_non_ptr), + + /* const/volatile/restrict and typedefs scenarios */ + MODS_CASE(mods), + MODS_CASE(mods___mod_swap), + MODS_CASE(mods___typedefs), + + /* handling "ptr is an array" semantics */ + PTR_AS_ARR_CASE(ptr_as_arr), + PTR_AS_ARR_CASE(ptr_as_arr___diff_sz), + + /* int signedness/sizing/bitfield handling */ + INTS_CASE(ints), + INTS_CASE(ints___bool), + INTS_CASE(ints___reverse_sign), + + INTS_ERR_CASE(ints___err_bitfield), + INTS_ERR_CASE(ints___err_wrong_sz_8), + INTS_ERR_CASE(ints___err_wrong_sz_16), + INTS_ERR_CASE(ints___err_wrong_sz_32), + INTS_ERR_CASE(ints___err_wrong_sz_64), + + /* validate edge cases of capturing relocations */ + { + .case_name = "misc", + .bpf_obj_file = "test_core_reloc_misc.o", + .btf_src_file = "btf__core_reloc_misc.o", + .input = (const char *)&(struct core_reloc_misc_extensible[]){ + { .a = 1 }, + { .a = 2 }, /* not read */ + { .a = 3 }, + }, + .input_len = 4 * sizeof(int), + .output = STRUCT_TO_CHAR_PTR(core_reloc_misc_output) { + .a = 1, + .b = 1, + .c = 0, /* BUG in clang, should be 3 */ + }, + .output_len = sizeof(struct core_reloc_misc_output), + }, +}; + +struct data { + char in[256]; + char out[256]; +}; + +void test_core_reloc(void) +{ + const char *probe_name = "raw_tracepoint/sys_enter"; + struct bpf_object_load_attr load_attr = {}; + struct core_reloc_test_case *test_case; + int err, duration = 0, i, equal; + struct bpf_link *link = NULL; + struct bpf_map *data_map; + struct bpf_program *prog; + struct bpf_object *obj; + const int zero = 0; + struct data data; + + for (i = 0; i < ARRAY_SIZE(test_cases); i++) { + test_case = &test_cases[i]; + + if (!test__start_subtest(test_case->case_name)) + continue; + + obj = bpf_object__open(test_case->bpf_obj_file); + if (CHECK(IS_ERR_OR_NULL(obj), "obj_open", + "failed to open '%s': %ld\n", + test_case->bpf_obj_file, PTR_ERR(obj))) + continue; + + prog = bpf_object__find_program_by_title(obj, probe_name); + if (CHECK(!prog, "find_probe", + "prog '%s' not found\n", probe_name)) + goto cleanup; + bpf_program__set_type(prog, BPF_PROG_TYPE_RAW_TRACEPOINT); + + load_attr.obj = obj; + load_attr.log_level = 0; + load_attr.target_btf_path = test_case->btf_src_file; + err = bpf_object__load_xattr(&load_attr); + if (test_case->fails) { + CHECK(!err, "obj_load_fail", + "should fail to load prog '%s'\n", probe_name); + goto cleanup; + } else { + if (CHECK(err, "obj_load", + "failed to load prog '%s': %d\n", + probe_name, err)) + goto cleanup; + } + + link = bpf_program__attach_raw_tracepoint(prog, "sys_enter"); + if (CHECK(IS_ERR(link), "attach_raw_tp", "err %ld\n", + PTR_ERR(link))) + goto cleanup; + + data_map = bpf_object__find_map_by_name(obj, "test_cor.bss"); + if (CHECK(!data_map, "find_data_map", "data map not found\n")) + goto cleanup; + + memset(&data, 0, sizeof(data)); + memcpy(data.in, test_case->input, test_case->input_len); + + err = bpf_map_update_elem(bpf_map__fd(data_map), + &zero, &data, 0); + if (CHECK(err, "update_data_map", + "failed to update .data map: %d\n", err)) + goto cleanup; + + /* trigger test run */ + usleep(1); + + err = bpf_map_lookup_elem(bpf_map__fd(data_map), &zero, &data); + if (CHECK(err, "get_result", + "failed to get output data: %d\n", err)) + goto cleanup; + + equal = memcmp(data.out, test_case->output, + test_case->output_len) == 0; + if (CHECK(!equal, "check_result", + "input/output data don't match\n")) { + int j; + + for (j = 0; j < test_case->input_len; j++) { + printf("input byte #%d: 0x%02hhx\n", + j, test_case->input[j]); + } + for (j = 0; j < test_case->output_len; j++) { + printf("output byte #%d: EXP 0x%02hhx GOT 0x%02hhx\n", + j, test_case->output[j], data.out[j]); + } + goto cleanup; + } + +cleanup: + if (!IS_ERR_OR_NULL(link)) { + bpf_link__destroy(link); + link = NULL; + } + bpf_object__close(obj); + } +} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays.c new file mode 100644 index 000000000000..018ed7fbba3a --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_arrays x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___diff_arr_dim.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___diff_arr_dim.c new file mode 100644 index 000000000000..13d662c57014 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___diff_arr_dim.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_arrays___diff_arr_dim x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___diff_arr_val_sz.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___diff_arr_val_sz.c new file mode 100644 index 000000000000..a351f418c85d --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___diff_arr_val_sz.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_arrays___diff_arr_val_sz x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_non_array.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_non_array.c new file mode 100644 index 000000000000..a8735009becc --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_non_array.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_arrays___err_non_array x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_too_shallow.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_too_shallow.c new file mode 100644 index 000000000000..2a67c28b1e75 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_too_shallow.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_arrays___err_too_shallow x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_too_small.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_too_small.c new file mode 100644 index 000000000000..1142c08c925f --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_too_small.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_arrays___err_too_small x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_wrong_val_type1.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_wrong_val_type1.c new file mode 100644 index 000000000000..795a5b729176 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_wrong_val_type1.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_arrays___err_wrong_val_type1 x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_wrong_val_type2.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_wrong_val_type2.c new file mode 100644 index 000000000000..3af74b837c4d --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_wrong_val_type2.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_arrays___err_wrong_val_type2 x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_flavors.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_flavors.c new file mode 100644 index 000000000000..b74455b91227 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_flavors.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_flavors x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_flavors__err_wrong_name.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_flavors__err_wrong_name.c new file mode 100644 index 000000000000..7b6035f86ee6 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_flavors__err_wrong_name.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_flavors__err_wrong_name x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_ints.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_ints.c new file mode 100644 index 000000000000..7d0f041042c5 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_ints.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_ints x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_ints___bool.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_ints___bool.c new file mode 100644 index 000000000000..f9359450186e --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_ints___bool.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_ints___bool x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_ints___err_bitfield.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_ints___err_bitfield.c new file mode 100644 index 000000000000..50369e8320a0 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_ints___err_bitfield.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_ints___err_bitfield x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_ints___err_wrong_sz_16.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_ints___err_wrong_sz_16.c new file mode 100644 index 000000000000..823bac13d641 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_ints___err_wrong_sz_16.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_ints___err_wrong_sz_16 x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_ints___err_wrong_sz_32.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_ints___err_wrong_sz_32.c new file mode 100644 index 000000000000..b44f3be18535 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_ints___err_wrong_sz_32.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_ints___err_wrong_sz_32 x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_ints___err_wrong_sz_64.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_ints___err_wrong_sz_64.c new file mode 100644 index 000000000000..9a3dd2099c0f --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_ints___err_wrong_sz_64.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_ints___err_wrong_sz_64 x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_ints___err_wrong_sz_8.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_ints___err_wrong_sz_8.c new file mode 100644 index 000000000000..9f11ef5f6e88 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_ints___err_wrong_sz_8.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_ints___err_wrong_sz_8 x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_ints___reverse_sign.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_ints___reverse_sign.c new file mode 100644 index 000000000000..aafb1c5819d7 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_ints___reverse_sign.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_ints___reverse_sign x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_misc.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_misc.c new file mode 100644 index 000000000000..ed9ad8b5b4f8 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_misc.c @@ -0,0 +1,5 @@ +#include "core_reloc_types.h" + +void f1(struct core_reloc_misc___a x) {} +void f2(struct core_reloc_misc___b x) {} +void f3(struct core_reloc_misc_extensible x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_mods.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_mods.c new file mode 100644 index 000000000000..124197a2e813 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_mods.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_mods x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_mods___mod_swap.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_mods___mod_swap.c new file mode 100644 index 000000000000..f8a6592ca75f --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_mods___mod_swap.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_mods___mod_swap x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_mods___typedefs.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_mods___typedefs.c new file mode 100644 index 000000000000..5c0d73687247 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_mods___typedefs.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_mods___typedefs x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting.c new file mode 100644 index 000000000000..4480fcc0f183 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_nesting x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___anon_embed.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___anon_embed.c new file mode 100644 index 000000000000..13e108f76ece --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___anon_embed.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_nesting___anon_embed x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___dup_compat_types.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___dup_compat_types.c new file mode 100644 index 000000000000..76b54fda5fbb --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___dup_compat_types.c @@ -0,0 +1,5 @@ +#include "core_reloc_types.h" + +void f1(struct core_reloc_nesting___dup_compat_types x) {} +void f2(struct core_reloc_nesting___dup_compat_types__2 x) {} +void f3(struct core_reloc_nesting___dup_compat_types__3 x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_array_container.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_array_container.c new file mode 100644 index 000000000000..975fb95db810 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_array_container.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_nesting___err_array_container x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_array_field.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_array_field.c new file mode 100644 index 000000000000..ad66c67e7980 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_array_field.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_nesting___err_array_field x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_dup_incompat_types.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_dup_incompat_types.c new file mode 100644 index 000000000000..35c5f8da6812 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_dup_incompat_types.c @@ -0,0 +1,4 @@ +#include "core_reloc_types.h" + +void f1(struct core_reloc_nesting___err_dup_incompat_types__1 x) {} +void f2(struct core_reloc_nesting___err_dup_incompat_types__2 x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_missing_container.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_missing_container.c new file mode 100644 index 000000000000..142e332041db --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_missing_container.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_nesting___err_missing_container x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_missing_field.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_missing_field.c new file mode 100644 index 000000000000..efcae167fab9 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_missing_field.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_nesting___err_missing_field x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_nonstruct_container.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_nonstruct_container.c new file mode 100644 index 000000000000..97aaaedd8ada --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_nonstruct_container.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_nesting___err_nonstruct_container x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_partial_match_dups.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_partial_match_dups.c new file mode 100644 index 000000000000..ffde35086e90 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_partial_match_dups.c @@ -0,0 +1,4 @@ +#include "core_reloc_types.h" + +void f1(struct core_reloc_nesting___err_partial_match_dups__a x) {} +void f2(struct core_reloc_nesting___err_partial_match_dups__b x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_too_deep.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_too_deep.c new file mode 100644 index 000000000000..39a2fadd8e95 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___err_too_deep.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_nesting___err_too_deep x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___extra_nesting.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___extra_nesting.c new file mode 100644 index 000000000000..a09d9dfb20df --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___extra_nesting.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_nesting___extra_nesting x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___struct_union_mixup.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___struct_union_mixup.c new file mode 100644 index 000000000000..3d8a1a74012f --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_nesting___struct_union_mixup.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_nesting___struct_union_mixup x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_primitives.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_primitives.c new file mode 100644 index 000000000000..96b90e39242a --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_primitives.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_primitives x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___diff_enum_def.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___diff_enum_def.c new file mode 100644 index 000000000000..6e87233a3ed0 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___diff_enum_def.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_primitives___diff_enum_def x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___diff_func_proto.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___diff_func_proto.c new file mode 100644 index 000000000000..d9f48e80b9d9 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___diff_func_proto.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_primitives___diff_func_proto x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___diff_ptr_type.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___diff_ptr_type.c new file mode 100644 index 000000000000..c718f75f8f3b --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___diff_ptr_type.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_primitives___diff_ptr_type x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___err_non_enum.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___err_non_enum.c new file mode 100644 index 000000000000..b8a120830891 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___err_non_enum.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_primitives___err_non_enum x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___err_non_int.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___err_non_int.c new file mode 100644 index 000000000000..ad8b3c9aa76f --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___err_non_int.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_primitives___err_non_int x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___err_non_ptr.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___err_non_ptr.c new file mode 100644 index 000000000000..e20bc1d42d0a --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_primitives___err_non_ptr.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_primitives___err_non_ptr x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_ptr_as_arr.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_ptr_as_arr.c new file mode 100644 index 000000000000..8da52432ba17 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_ptr_as_arr.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_ptr_as_arr x) {} diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_ptr_as_arr___diff_sz.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_ptr_as_arr___diff_sz.c new file mode 100644 index 000000000000..003acfc9a3e7 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_ptr_as_arr___diff_sz.c @@ -0,0 +1,3 @@ +#include "core_reloc_types.h" + +void f(struct core_reloc_ptr_as_arr___diff_sz x) {} diff --git a/tools/testing/selftests/bpf/progs/core_reloc_types.h b/tools/testing/selftests/bpf/progs/core_reloc_types.h new file mode 100644 index 000000000000..10a252b6da55 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/core_reloc_types.h @@ -0,0 +1,667 @@ +#include <stdint.h> +#include <stdbool.h> + +/* + * FLAVORS + */ +struct core_reloc_flavors { + int a; + int b; + int c; +}; + +/* this is not a flavor, as it doesn't have triple underscore */ +struct core_reloc_flavors__err_wrong_name { + int a; + int b; + int c; +}; + +/* + * NESTING + */ +/* original set up, used to record relocations in BPF program */ +struct core_reloc_nesting_substruct { + int a; +}; + +union core_reloc_nesting_subunion { + int b; +}; + +struct core_reloc_nesting { + union { + struct core_reloc_nesting_substruct a; + } a; + struct { + union core_reloc_nesting_subunion b; + } b; +}; + +/* inlined anonymous struct/union instead of named structs in original */ +struct core_reloc_nesting___anon_embed { + int __just_for_padding; + union { + struct { + int a; + } a; + } a; + struct { + union { + int b; + } b; + } b; +}; + +/* different mix of nested structs/unions than in original */ +struct core_reloc_nesting___struct_union_mixup { + int __a; + struct { + int __a; + union { + char __a; + int a; + } a; + } a; + int __b; + union { + int __b; + union { + char __b; + int b; + } b; + } b; +}; + +/* extra anon structs/unions, but still valid a.a.a and b.b.b accessors */ +struct core_reloc_nesting___extra_nesting { + int __padding; + struct { + struct { + struct { + struct { + union { + int a; + } a; + }; + }; + } a; + int __some_more; + struct { + union { + union { + union { + struct { + int b; + }; + } b; + }; + } b; + }; + }; +}; + +/* three flavors of same struct with different structure but same layout for + * a.a.a and b.b.b, thus successfully resolved and relocatable */ +struct core_reloc_nesting___dup_compat_types { + char __just_for_padding; + /* 3 more bytes of padding */ + struct { + struct { + int a; /* offset 4 */ + } a; + } a; + long long __more_padding; + struct { + struct { + int b; /* offset 16 */ + } b; + } b; +}; + +struct core_reloc_nesting___dup_compat_types__2 { + int __aligned_padding; + struct { + int __trickier_noop[0]; + struct { + char __some_more_noops[0]; + int a; /* offset 4 */ + } a; + } a; + int __more_padding; + struct { + struct { + struct { + int __critical_padding; + int b; /* offset 16 */ + } b; + int __does_not_matter; + }; + } b; + int __more_irrelevant_stuff; +}; + +struct core_reloc_nesting___dup_compat_types__3 { + char __correct_padding[4]; + struct { + struct { + int a; /* offset 4 */ + } a; + } a; + /* 8 byte padding due to next struct's alignment */ + struct { + struct { + int b; + } b; + } b __attribute__((aligned(16))); +}; + +/* b.b.b field is missing */ +struct core_reloc_nesting___err_missing_field { + struct { + struct { + int a; + } a; + } a; + struct { + struct { + int x; + } b; + } b; +}; + +/* b.b.b field is an array of integers instead of plain int */ +struct core_reloc_nesting___err_array_field { + struct { + struct { + int a; + } a; + } a; + struct { + struct { + int b[1]; + } b; + } b; +}; + +/* middle b container is missing */ +struct core_reloc_nesting___err_missing_container { + struct { + struct { + int a; + } a; + } a; + struct { + int x; + } b; +}; + +/* middle b container is referenced through pointer instead of being embedded */ +struct core_reloc_nesting___err_nonstruct_container { + struct { + struct { + int a; + } a; + } a; + struct { + struct { + int b; + } *b; + } b; +}; + +/* middle b container is an array of structs instead of plain struct */ +struct core_reloc_nesting___err_array_container { + struct { + struct { + int a; + } a; + } a; + struct { + struct { + int b; + } b[1]; + } b; +}; + +/* two flavors of same struct with incompatible layout for b.b.b */ +struct core_reloc_nesting___err_dup_incompat_types__1 { + struct { + struct { + int a; /* offset 0 */ + } a; + } a; + struct { + struct { + int b; /* offset 4 */ + } b; + } b; +}; + +struct core_reloc_nesting___err_dup_incompat_types__2 { + struct { + struct { + int a; /* offset 0 */ + } a; + } a; + int __extra_padding; + struct { + struct { + int b; /* offset 8 (!) */ + } b; + } b; +}; + +/* two flavors of same struct having one of a.a.a and b.b.b, but not both */ +struct core_reloc_nesting___err_partial_match_dups__a { + struct { + struct { + int a; + } a; + } a; +}; + +struct core_reloc_nesting___err_partial_match_dups__b { + struct { + struct { + int b; + } b; + } b; +}; + +struct core_reloc_nesting___err_too_deep { + struct { + struct { + int a; + } a; + } a; + /* 65 levels of nestedness for b.b.b */ + struct { + struct { + struct { struct { struct { struct { struct { + struct { struct { struct { struct { struct { + struct { struct { struct { struct { struct { + struct { struct { struct { struct { struct { + struct { struct { struct { struct { struct { + struct { struct { struct { struct { struct { + struct { struct { struct { struct { struct { + struct { struct { struct { struct { struct { + struct { struct { struct { struct { struct { + struct { struct { struct { struct { struct { + struct { struct { struct { struct { struct { + struct { struct { struct { struct { struct { + /* this one is one too much */ + struct { + int b; + }; + }; }; }; }; }; + }; }; }; }; }; + }; }; }; }; }; + }; }; }; }; }; + }; }; }; }; }; + }; }; }; }; }; + }; }; }; }; }; + }; }; }; }; }; + }; }; }; }; }; + }; }; }; }; }; + }; }; }; }; }; + }; }; }; }; }; + } b; + } b; +}; + +/* + * ARRAYS + */ +struct core_reloc_arrays_output { + int a2; + char b123; + int c1c; + int d00d; +}; + +struct core_reloc_arrays_substruct { + int c; + int d; +}; + +struct core_reloc_arrays { + int a[5]; + char b[2][3][4]; + struct core_reloc_arrays_substruct c[3]; + struct core_reloc_arrays_substruct d[1][2]; +}; + +/* bigger array dimensions */ +struct core_reloc_arrays___diff_arr_dim { + int a[7]; + char b[3][4][5]; + struct core_reloc_arrays_substruct c[4]; + struct core_reloc_arrays_substruct d[2][3]; +}; + +/* different size of array's value (struct) */ +struct core_reloc_arrays___diff_arr_val_sz { + int a[5]; + char b[2][3][4]; + struct { + int __padding1; + int c; + int __padding2; + } c[3]; + struct { + int __padding1; + int d; + int __padding2; + } d[1][2]; +}; + +struct core_reloc_arrays___err_too_small { + int a[2]; /* this one is too small */ + char b[2][3][4]; + struct core_reloc_arrays_substruct c[3]; + struct core_reloc_arrays_substruct d[1][2]; +}; + +struct core_reloc_arrays___err_too_shallow { + int a[5]; + char b[2][3]; /* this one lacks one dimension */ + struct core_reloc_arrays_substruct c[3]; + struct core_reloc_arrays_substruct d[1][2]; +}; + +struct core_reloc_arrays___err_non_array { + int a; /* not an array */ + char b[2][3][4]; + struct core_reloc_arrays_substruct c[3]; + struct core_reloc_arrays_substruct d[1][2]; +}; + +struct core_reloc_arrays___err_wrong_val_type1 { + char a[5]; /* char instead of int */ + char b[2][3][4]; + struct core_reloc_arrays_substruct c[3]; + struct core_reloc_arrays_substruct d[1][2]; +}; + +struct core_reloc_arrays___err_wrong_val_type2 { + int a[5]; + char b[2][3][4]; + int c[3]; /* value is not a struct */ + struct core_reloc_arrays_substruct d[1][2]; +}; + +/* + * PRIMITIVES + */ +enum core_reloc_primitives_enum { + A = 0, + B = 1, +}; + +struct core_reloc_primitives { + char a; + int b; + enum core_reloc_primitives_enum c; + void *d; + int (*f)(const char *); +}; + +struct core_reloc_primitives___diff_enum_def { + char a; + int b; + void *d; + int (*f)(const char *); + enum { + X = 100, + Y = 200, + } c; /* inline enum def with differing set of values */ +}; + +struct core_reloc_primitives___diff_func_proto { + void (*f)(int); /* incompatible function prototype */ + void *d; + enum core_reloc_primitives_enum c; + int b; + char a; +}; + +struct core_reloc_primitives___diff_ptr_type { + const char * const d; /* different pointee type + modifiers */ + char a; + int b; + enum core_reloc_primitives_enum c; + int (*f)(const char *); +}; + +struct core_reloc_primitives___err_non_enum { + char a[1]; + int b; + int c; /* int instead of enum */ + void *d; + int (*f)(const char *); +}; + +struct core_reloc_primitives___err_non_int { + char a[1]; + int *b; /* ptr instead of int */ + enum core_reloc_primitives_enum c; + void *d; + int (*f)(const char *); +}; + +struct core_reloc_primitives___err_non_ptr { + char a[1]; + int b; + enum core_reloc_primitives_enum c; + int d; /* int instead of ptr */ + int (*f)(const char *); +}; + +/* + * MODS + */ +struct core_reloc_mods_output { + int a, b, c, d, e, f, g, h; +}; + +typedef const int int_t; +typedef const char *char_ptr_t; +typedef const int arr_t[7]; + +struct core_reloc_mods_substruct { + int x; + int y; +}; + +typedef struct { + int x; + int y; +} core_reloc_mods_substruct_t; + +struct core_reloc_mods { + int a; + int_t b; + char *c; + char_ptr_t d; + int e[3]; + arr_t f; + struct core_reloc_mods_substruct g; + core_reloc_mods_substruct_t h; +}; + +/* a/b, c/d, e/f, and g/h pairs are swapped */ +struct core_reloc_mods___mod_swap { + int b; + int_t a; + char *d; + char_ptr_t c; + int f[3]; + arr_t e; + struct { + int y; + int x; + } h; + core_reloc_mods_substruct_t g; +}; + +typedef int int1_t; +typedef int1_t int2_t; +typedef int2_t int3_t; + +typedef int arr1_t[5]; +typedef arr1_t arr2_t; +typedef arr2_t arr3_t; +typedef arr3_t arr4_t; + +typedef const char * const volatile restrict fancy_char_ptr_t; + +typedef core_reloc_mods_substruct_t core_reloc_mods_substruct_tt; + +/* we need more typedefs */ +struct core_reloc_mods___typedefs { + core_reloc_mods_substruct_tt g; + core_reloc_mods_substruct_tt h; + arr4_t f; + arr4_t e; + fancy_char_ptr_t d; + fancy_char_ptr_t c; + int3_t b; + int3_t a; +}; + +/* + * PTR_AS_ARR + */ +struct core_reloc_ptr_as_arr { + int a; +}; + +struct core_reloc_ptr_as_arr___diff_sz { + int :32; /* padding */ + char __some_more_padding; + int a; +}; + +/* + * INTS + */ +struct core_reloc_ints { + uint8_t u8_field; + int8_t s8_field; + uint16_t u16_field; + int16_t s16_field; + uint32_t u32_field; + int32_t s32_field; + uint64_t u64_field; + int64_t s64_field; +}; + +/* signed/unsigned types swap */ +struct core_reloc_ints___reverse_sign { + int8_t u8_field; + uint8_t s8_field; + int16_t u16_field; + uint16_t s16_field; + int32_t u32_field; + uint32_t s32_field; + int64_t u64_field; + uint64_t s64_field; +}; + +struct core_reloc_ints___bool { + bool u8_field; /* bool instead of uint8 */ + int8_t s8_field; + uint16_t u16_field; + int16_t s16_field; + uint32_t u32_field; + int32_t s32_field; + uint64_t u64_field; + int64_t s64_field; +}; + +struct core_reloc_ints___err_bitfield { + uint8_t u8_field; + int8_t s8_field; + uint16_t u16_field; + int16_t s16_field; + uint32_t u32_field: 32; /* bitfields are not supported */ + int32_t s32_field; + uint64_t u64_field; + int64_t s64_field; +}; + +struct core_reloc_ints___err_wrong_sz_8 { + uint16_t u8_field; /* not 8-bit anymore */ + int16_t s8_field; /* not 8-bit anymore */ + + uint16_t u16_field; + int16_t s16_field; + uint32_t u32_field; + int32_t s32_field; + uint64_t u64_field; + int64_t s64_field; +}; + +struct core_reloc_ints___err_wrong_sz_16 { + uint8_t u8_field; + int8_t s8_field; + + uint32_t u16_field; /* not 16-bit anymore */ + int32_t s16_field; /* not 16-bit anymore */ + + uint32_t u32_field; + int32_t s32_field; + uint64_t u64_field; + int64_t s64_field; +}; + +struct core_reloc_ints___err_wrong_sz_32 { + uint8_t u8_field; + int8_t s8_field; + uint16_t u16_field; + int16_t s16_field; + + uint64_t u32_field; /* not 32-bit anymore */ + int64_t s32_field; /* not 32-bit anymore */ + + uint64_t u64_field; + int64_t s64_field; +}; + +struct core_reloc_ints___err_wrong_sz_64 { + uint8_t u8_field; + int8_t s8_field; + uint16_t u16_field; + int16_t s16_field; + uint32_t u32_field; + int32_t s32_field; + + uint32_t u64_field; /* not 64-bit anymore */ + int32_t s64_field; /* not 64-bit anymore */ +}; + +/* + * MISC + */ +struct core_reloc_misc_output { + int a, b, c; +}; + +struct core_reloc_misc___a { + int a1; + int a2; +}; + +struct core_reloc_misc___b { + int b1; + int b2; +}; + +/* this one extends core_reloc_misc_extensible struct from BPF prog */ +struct core_reloc_misc_extensible { + int a; + int b; + int c; + int d; +}; diff --git a/tools/testing/selftests/bpf/progs/test_core_reloc_arrays.c b/tools/testing/selftests/bpf/progs/test_core_reloc_arrays.c new file mode 100644 index 000000000000..bf67f0fdf743 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_core_reloc_arrays.c @@ -0,0 +1,55 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2019 Facebook + +#include <linux/bpf.h> +#include <stdint.h> +#include "bpf_helpers.h" + +char _license[] SEC("license") = "GPL"; + +static volatile struct data { + char in[256]; + char out[256]; +} data; + +struct core_reloc_arrays_output { + int a2; + char b123; + int c1c; + int d00d; +}; + +struct core_reloc_arrays_substruct { + int c; + int d; +}; + +struct core_reloc_arrays { + int a[5]; + char b[2][3][4]; + struct core_reloc_arrays_substruct c[3]; + struct core_reloc_arrays_substruct d[1][2]; +}; + +SEC("raw_tracepoint/sys_enter") +int test_core_arrays(void *ctx) +{ + struct core_reloc_arrays *in = (void *)&data.in; + struct core_reloc_arrays_output *out = (void *)&data.out; + + /* in->a[2] */ + if (BPF_CORE_READ(&out->a2, &in->a[2])) + return 1; + /* in->b[1][2][3] */ + if (BPF_CORE_READ(&out->b123, &in->b[1][2][3])) + return 1; + /* in->c[1].c */ + if (BPF_CORE_READ(&out->c1c, &in->c[1].c)) + return 1; + /* in->d[0][0].d */ + if (BPF_CORE_READ(&out->d00d, &in->d[0][0].d)) + return 1; + + return 0; +} + diff --git a/tools/testing/selftests/bpf/progs/test_core_reloc_flavors.c b/tools/testing/selftests/bpf/progs/test_core_reloc_flavors.c new file mode 100644 index 000000000000..9fda73e87972 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_core_reloc_flavors.c @@ -0,0 +1,62 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2019 Facebook + +#include <linux/bpf.h> +#include <stdint.h> +#include "bpf_helpers.h" + +char _license[] SEC("license") = "GPL"; + +static volatile struct data { + char in[256]; + char out[256]; +} data; + +struct core_reloc_flavors { + int a; + int b; + int c; +}; + +/* local flavor with reversed layout */ +struct core_reloc_flavors___reversed { + int c; + int b; + int a; +}; + +/* local flavor with nested/overlapping layout */ +struct core_reloc_flavors___weird { + struct { + int b; + }; + /* a and c overlap in local flavor, but this should still work + * correctly with target original flavor + */ + union { + int a; + int c; + }; +}; + +SEC("raw_tracepoint/sys_enter") +int test_core_flavors(void *ctx) +{ + struct core_reloc_flavors *in_orig = (void *)&data.in; + struct core_reloc_flavors___reversed *in_rev = (void *)&data.in; + struct core_reloc_flavors___weird *in_weird = (void *)&data.in; + struct core_reloc_flavors *out = (void *)&data.out; + + /* read a using weird layout */ + if (BPF_CORE_READ(&out->a, &in_weird->a)) + return 1; + /* read b using reversed layout */ + if (BPF_CORE_READ(&out->b, &in_rev->b)) + return 1; + /* read c using original layout */ + if (BPF_CORE_READ(&out->c, &in_orig->c)) + return 1; + + return 0; +} + diff --git a/tools/testing/selftests/bpf/progs/test_core_reloc_ints.c b/tools/testing/selftests/bpf/progs/test_core_reloc_ints.c new file mode 100644 index 000000000000..d99233c8008a --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_core_reloc_ints.c @@ -0,0 +1,44 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2019 Facebook + +#include <linux/bpf.h> +#include <stdint.h> +#include "bpf_helpers.h" + +char _license[] SEC("license") = "GPL"; + +static volatile struct data { + char in[256]; + char out[256]; +} data; + +struct core_reloc_ints { + uint8_t u8_field; + int8_t s8_field; + uint16_t u16_field; + int16_t s16_field; + uint32_t u32_field; + int32_t s32_field; + uint64_t u64_field; + int64_t s64_field; +}; + +SEC("raw_tracepoint/sys_enter") +int test_core_ints(void *ctx) +{ + struct core_reloc_ints *in = (void *)&data.in; + struct core_reloc_ints *out = (void *)&data.out; + + if (BPF_CORE_READ(&out->u8_field, &in->u8_field) || + BPF_CORE_READ(&out->s8_field, &in->s8_field) || + BPF_CORE_READ(&out->u16_field, &in->u16_field) || + BPF_CORE_READ(&out->s16_field, &in->s16_field) || + BPF_CORE_READ(&out->u32_field, &in->u32_field) || + BPF_CORE_READ(&out->s32_field, &in->s32_field) || + BPF_CORE_READ(&out->u64_field, &in->u64_field) || + BPF_CORE_READ(&out->s64_field, &in->s64_field)) + return 1; + + return 0; +} + diff --git a/tools/testing/selftests/bpf/progs/test_core_reloc_kernel.c b/tools/testing/selftests/bpf/progs/test_core_reloc_kernel.c new file mode 100644 index 000000000000..37e02aa3f0c8 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_core_reloc_kernel.c @@ -0,0 +1,36 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2019 Facebook + +#include <linux/bpf.h> +#include <stdint.h> +#include "bpf_helpers.h" + +char _license[] SEC("license") = "GPL"; + +static volatile struct data { + char in[256]; + char out[256]; +} data; + +struct task_struct { + int pid; + int tgid; +}; + +SEC("raw_tracepoint/sys_enter") +int test_core_kernel(void *ctx) +{ + struct task_struct *task = (void *)bpf_get_current_task(); + uint64_t pid_tgid = bpf_get_current_pid_tgid(); + int pid, tgid; + + if (BPF_CORE_READ(&pid, &task->pid) || + BPF_CORE_READ(&tgid, &task->tgid)) + return 1; + + /* validate pid + tgid matches */ + data.out[0] = (((uint64_t)pid << 32) | tgid) == pid_tgid; + + return 0; +} + diff --git a/tools/testing/selftests/bpf/progs/test_core_reloc_misc.c b/tools/testing/selftests/bpf/progs/test_core_reloc_misc.c new file mode 100644 index 000000000000..c59984bd3e23 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_core_reloc_misc.c @@ -0,0 +1,57 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2019 Facebook + +#include <linux/bpf.h> +#include <stdint.h> +#include "bpf_helpers.h" + +char _license[] SEC("license") = "GPL"; + +static volatile struct data { + char in[256]; + char out[256]; +} data; + +struct core_reloc_misc_output { + int a, b, c; +}; + +struct core_reloc_misc___a { + int a1; + int a2; +}; + +struct core_reloc_misc___b { + int b1; + int b2; +}; + +/* fixed two first members, can be extended with new fields */ +struct core_reloc_misc_extensible { + int a; + int b; +}; + +SEC("raw_tracepoint/sys_enter") +int test_core_misc(void *ctx) +{ + struct core_reloc_misc___a *in_a = (void *)&data.in; + struct core_reloc_misc___b *in_b = (void *)&data.in; + struct core_reloc_misc_extensible *in_ext = (void *)&data.in; + struct core_reloc_misc_output *out = (void *)&data.out; + + /* record two different relocations with the same accessor string */ + if (BPF_CORE_READ(&out->a, &in_a->a1) || /* accessor: 0:0 */ + BPF_CORE_READ(&out->b, &in_b->b1)) /* accessor: 0:0 */ + return 1; + + /* Validate relocations capture array-only accesses for structs with + * fixed header, but with potentially extendable tail. This will read + * first 4 bytes of 2nd element of in_ext array of potentially + * variably sized struct core_reloc_misc_extensible. */ + if (BPF_CORE_READ(&out->c, &in_ext[2])) /* accessor: 2 */ + return 1; + + return 0; +} + diff --git a/tools/testing/selftests/bpf/progs/test_core_reloc_mods.c b/tools/testing/selftests/bpf/progs/test_core_reloc_mods.c new file mode 100644 index 000000000000..f98b942c062b --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_core_reloc_mods.c @@ -0,0 +1,62 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2019 Facebook + +#include <linux/bpf.h> +#include <stdint.h> +#include "bpf_helpers.h" + +char _license[] SEC("license") = "GPL"; + +static volatile struct data { + char in[256]; + char out[256]; +} data; + +struct core_reloc_mods_output { + int a, b, c, d, e, f, g, h; +}; + +typedef const int int_t; +typedef const char *char_ptr_t; +typedef const int arr_t[7]; + +struct core_reloc_mods_substruct { + int x; + int y; +}; + +typedef struct { + int x; + int y; +} core_reloc_mods_substruct_t; + +struct core_reloc_mods { + int a; + int_t b; + char *c; + char_ptr_t d; + int e[3]; + arr_t f; + struct core_reloc_mods_substruct g; + core_reloc_mods_substruct_t h; +}; + +SEC("raw_tracepoint/sys_enter") +int test_core_mods(void *ctx) +{ + struct core_reloc_mods *in = (void *)&data.in; + struct core_reloc_mods_output *out = (void *)&data.out; + + if (BPF_CORE_READ(&out->a, &in->a) || + BPF_CORE_READ(&out->b, &in->b) || + BPF_CORE_READ(&out->c, &in->c) || + BPF_CORE_READ(&out->d, &in->d) || + BPF_CORE_READ(&out->e, &in->e[2]) || + BPF_CORE_READ(&out->f, &in->f[1]) || + BPF_CORE_READ(&out->g, &in->g.x) || + BPF_CORE_READ(&out->h, &in->h.y)) + return 1; + + return 0; +} + diff --git a/tools/testing/selftests/bpf/progs/test_core_reloc_nesting.c b/tools/testing/selftests/bpf/progs/test_core_reloc_nesting.c new file mode 100644 index 000000000000..3ca30cec2b39 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_core_reloc_nesting.c @@ -0,0 +1,46 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2019 Facebook + +#include <linux/bpf.h> +#include <stdint.h> +#include "bpf_helpers.h" + +char _license[] SEC("license") = "GPL"; + +static volatile struct data { + char in[256]; + char out[256]; +} data; + +struct core_reloc_nesting_substruct { + int a; +}; + +union core_reloc_nesting_subunion { + int b; +}; + +/* int a.a.a and b.b.b accesses */ +struct core_reloc_nesting { + union { + struct core_reloc_nesting_substruct a; + } a; + struct { + union core_reloc_nesting_subunion b; + } b; +}; + +SEC("raw_tracepoint/sys_enter") +int test_core_nesting(void *ctx) +{ + struct core_reloc_nesting *in = (void *)&data.in; + struct core_reloc_nesting *out = (void *)&data.out; + + if (BPF_CORE_READ(&out->a.a.a, &in->a.a.a)) + return 1; + if (BPF_CORE_READ(&out->b.b.b, &in->b.b.b)) + return 1; + + return 0; +} + diff --git a/tools/testing/selftests/bpf/progs/test_core_reloc_primitives.c b/tools/testing/selftests/bpf/progs/test_core_reloc_primitives.c new file mode 100644 index 000000000000..add52f23ab35 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_core_reloc_primitives.c @@ -0,0 +1,43 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2019 Facebook + +#include <linux/bpf.h> +#include <stdint.h> +#include "bpf_helpers.h" + +char _license[] SEC("license") = "GPL"; + +static volatile struct data { + char in[256]; + char out[256]; +} data; + +enum core_reloc_primitives_enum { + A = 0, + B = 1, +}; + +struct core_reloc_primitives { + char a; + int b; + enum core_reloc_primitives_enum c; + void *d; + int (*f)(const char *); +}; + +SEC("raw_tracepoint/sys_enter") +int test_core_primitives(void *ctx) +{ + struct core_reloc_primitives *in = (void *)&data.in; + struct core_reloc_primitives *out = (void *)&data.out; + + if (BPF_CORE_READ(&out->a, &in->a) || + BPF_CORE_READ(&out->b, &in->b) || + BPF_CORE_READ(&out->c, &in->c) || + BPF_CORE_READ(&out->d, &in->d) || + BPF_CORE_READ(&out->f, &in->f)) + return 1; + + return 0; +} + diff --git a/tools/testing/selftests/bpf/progs/test_core_reloc_ptr_as_arr.c b/tools/testing/selftests/bpf/progs/test_core_reloc_ptr_as_arr.c new file mode 100644 index 000000000000..526b7ddc7ea1 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_core_reloc_ptr_as_arr.c @@ -0,0 +1,30 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2019 Facebook + +#include <linux/bpf.h> +#include <stdint.h> +#include "bpf_helpers.h" + +char _license[] SEC("license") = "GPL"; + +static volatile struct data { + char in[256]; + char out[256]; +} data; + +struct core_reloc_ptr_as_arr { + int a; +}; + +SEC("raw_tracepoint/sys_enter") +int test_core_ptr_as_arr(void *ctx) +{ + struct core_reloc_ptr_as_arr *in = (void *)&data.in; + struct core_reloc_ptr_as_arr *out = (void *)&data.out; + + if (BPF_CORE_READ(&out->a, &in[2].a)) + return 1; + + return 0; +} + |