From patchwork Wed Jun 22 17:35:05 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Daniel_M=C3=BCller?= X-Patchwork-Id: 12891217 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CF506C433EF for ; Wed, 22 Jun 2022 17:35:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229763AbiFVRfU (ORCPT ); Wed, 22 Jun 2022 13:35:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41916 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229593AbiFVRfT (ORCPT ); Wed, 22 Jun 2022 13:35:19 -0400 Received: from mout01.posteo.de (mout01.posteo.de [185.67.36.65]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5974431DDD for ; Wed, 22 Jun 2022 10:35:18 -0700 (PDT) Received: from submission (posteo.de [185.67.36.169]) by mout01.posteo.de (Postfix) with ESMTPS id CE810240027 for ; Wed, 22 Jun 2022 19:35:16 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=posteo.net; s=2017; t=1655919316; bh=Fet6ovzBUh+b3fMdS2OSjxPeOKwsGtvEPoU+B6fz2Ks=; h=From:To:Subject:Date:From; b=XhEdIcLnB1fb3EcR7KQM4jtQSjF4D4syDo/qdWld6iNC7bIsYPffpK520GJK/SbDB 7gCx+NwLleNZvV2ag4cA8LEdo2Rgu672tqW2ItI7OG/DIe3BYONTMqQAnnXcegNvH4 J8qe2PPbQhGnhgI7XTS4p+/BxRND/iHfLEK8WhWdgcF2sV4wL41cEuo1OIaX6Md3HE u8xPH+baxcEl7WHQ57Wmeqe7IHQ6lLhPSsBqJsfRTx1LTY6fNHCpMhggYPvPmHP3FB 4/uYImjjdjkoyPB8pRbn6loRqEsNYMTVs0jBNFenQHMsB3u3TbRyqACLsqf9wkQFWx 48PRstLLQ1liQ== Received: from customer (localhost [127.0.0.1]) by submission (posteo.de) with ESMTPSA id 4LSrBC6qS9z6tmb; Wed, 22 Jun 2022 19:35:15 +0200 (CEST) From: =?utf-8?q?Daniel_M=C3=BCller?= To: bpf@vger.kernel.org, ast@kernel.org, andrii@kernel.org, daniel@iogearbox.net, kernel-team@fb.com Subject: [PATCH bpf-next 1/2] libbpf: Move core "types_are_compat" logic into relo_core.c Date: Wed, 22 Jun 2022 17:35:05 +0000 Message-Id: <20220622173506.860578-2-deso@posteo.net> In-Reply-To: <20220622173506.860578-1-deso@posteo.net> References: <20220622173506.860578-1-deso@posteo.net> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net This change merges the two existing implementations of the bpf_core_types_are_compat() function into relo_core.c, inheriting the recursion tracking from the kernel and the usage of btf_kind_core_compat() from libbpf. The kernel is left untouched and will be adjusted subsequently. Signed-off-by: Daniel Müller --- tools/lib/bpf/libbpf.c | 72 +----------------------------------- tools/lib/bpf/relo_core.c | 78 +++++++++++++++++++++++++++++++++++++++ tools/lib/bpf/relo_core.h | 2 + 3 files changed, 81 insertions(+), 71 deletions(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 49e359c..ca912c 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -5732,77 +5732,7 @@ bpf_core_find_cands(struct bpf_object *obj, const struct btf *local_btf, __u32 l int bpf_core_types_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; - int depth = 32; /* max recursion depth */ - - /* caller made sure that names match (ignoring flavor suffix) */ - local_type = btf__type_by_id(local_btf, local_id); - targ_type = btf__type_by_id(targ_btf, targ_id); - if (!btf_kind_core_compat(local_type, targ_type)) - return 0; - -recur: - depth--; - if (depth < 0) - return -EINVAL; - - 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_kind_core_compat(local_type, targ_type)) - return 0; - - switch (btf_kind(local_type)) { - case BTF_KIND_UNKN: - case BTF_KIND_STRUCT: - case BTF_KIND_UNION: - case BTF_KIND_ENUM: - case BTF_KIND_ENUM64: - case BTF_KIND_FWD: - return 1; - case BTF_KIND_INT: - /* just reject deprecated bitfield-like integers; all other - * integers are by default compatible between each other - */ - return btf_int_offset(local_type) == 0 && btf_int_offset(targ_type) == 0; - case BTF_KIND_PTR: - local_id = local_type->type; - targ_id = targ_type->type; - goto recur; - case BTF_KIND_ARRAY: - local_id = btf_array(local_type)->type; - targ_id = btf_array(targ_type)->type; - goto recur; - case BTF_KIND_FUNC_PROTO: { - struct btf_param *local_p = btf_params(local_type); - struct btf_param *targ_p = btf_params(targ_type); - __u16 local_vlen = btf_vlen(local_type); - __u16 targ_vlen = btf_vlen(targ_type); - int i, err; - - if (local_vlen != targ_vlen) - return 0; - - for (i = 0; i < local_vlen; i++, local_p++, targ_p++) { - skip_mods_and_typedefs(local_btf, local_p->type, &local_id); - skip_mods_and_typedefs(targ_btf, targ_p->type, &targ_id); - err = bpf_core_types_are_compat(local_btf, local_id, targ_btf, targ_id); - if (err <= 0) - return err; - } - - /* tail recurse for return type check */ - skip_mods_and_typedefs(local_btf, local_type->type, &local_id); - skip_mods_and_typedefs(targ_btf, targ_type->type, &targ_id); - goto recur; - } - default: - pr_warn("unexpected kind %s relocated, local [%d], target [%d]\n", - btf_kind_str(local_type), local_id, targ_id); - return 0; - } + return bpf_core_types_are_compat_recur(local_btf, local_id, targ_btf, targ_id, INT_MAX); } static size_t bpf_core_hash_fn(const void *key, void *ctx) diff --git a/tools/lib/bpf/relo_core.c b/tools/lib/bpf/relo_core.c index 6ad3c3..e54370 100644 --- a/tools/lib/bpf/relo_core.c +++ b/tools/lib/bpf/relo_core.c @@ -141,6 +141,84 @@ static bool core_relo_is_enumval_based(enum bpf_core_relo_kind kind) } } +int bpf_core_types_are_compat_recur(const struct btf *local_btf, __u32 local_id, + const struct btf *targ_btf, __u32 targ_id, int level) +{ + const struct btf_type *local_type, *targ_type; + int depth = 32; /* max recursion depth */ + + /* caller made sure that names match (ignoring flavor suffix) */ + local_type = btf_type_by_id(local_btf, local_id); + targ_type = btf_type_by_id(targ_btf, targ_id); + if (!btf_kind_core_compat(local_type, targ_type)) + return 0; + +recur: + depth--; + if (depth < 0) + return -EINVAL; + + 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_kind_core_compat(local_type, targ_type)) + return 0; + + switch (btf_kind(local_type)) { + case BTF_KIND_UNKN: + case BTF_KIND_STRUCT: + case BTF_KIND_UNION: + case BTF_KIND_ENUM: + case BTF_KIND_FWD: + case BTF_KIND_ENUM64: + return 1; + case BTF_KIND_INT: + /* just reject deprecated bitfield-like integers; all other + * integers are by default compatible between each other + */ + return btf_int_offset(local_type) == 0 && btf_int_offset(targ_type) == 0; + case BTF_KIND_PTR: + local_id = local_type->type; + targ_id = targ_type->type; + goto recur; + case BTF_KIND_ARRAY: + local_id = btf_array(local_type)->type; + targ_id = btf_array(targ_type)->type; + goto recur; + case BTF_KIND_FUNC_PROTO: { + struct btf_param *local_p = btf_params(local_type); + struct btf_param *targ_p = btf_params(targ_type); + __u16 local_vlen = btf_vlen(local_type); + __u16 targ_vlen = btf_vlen(targ_type); + int i, err; + + if (local_vlen != targ_vlen) + return 0; + + for (i = 0; i < local_vlen; i++, local_p++, targ_p++) { + if (level <= 0) + return -EINVAL; + + skip_mods_and_typedefs(local_btf, local_p->type, &local_id); + skip_mods_and_typedefs(targ_btf, targ_p->type, &targ_id); + err = bpf_core_types_are_compat_recur(local_btf, local_id, targ_btf, + targ_id, level - 1); + if (err <= 0) + return err; + } + + /* tail recurse for return type check */ + skip_mods_and_typedefs(local_btf, local_type->type, &local_id); + skip_mods_and_typedefs(targ_btf, targ_type->type, &targ_id); + goto recur; + } + default: + return 0; + } +} + /* * Turn bpf_core_relo into a low- and high-level spec representation, * validating correctness along the way, as well as calculating resulting diff --git a/tools/lib/bpf/relo_core.h b/tools/lib/bpf/relo_core.h index 7df0da0..b8998f 100644 --- a/tools/lib/bpf/relo_core.h +++ b/tools/lib/bpf/relo_core.h @@ -68,6 +68,8 @@ struct bpf_core_relo_res { __u32 new_type_id; }; +int bpf_core_types_are_compat_recur(const struct btf *local_btf, __u32 local_id, + const struct btf *targ_btf, __u32 targ_id, int level); int bpf_core_types_are_compat(const struct btf *local_btf, __u32 local_id, const struct btf *targ_btf, __u32 targ_id);