From nobody Sun Dec 28 09:52:20 2025 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 828D3C4167B for ; Fri, 8 Dec 2023 21:51:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1574794AbjLHVvY (ORCPT ); Fri, 8 Dec 2023 16:51:24 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52560 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229572AbjLHVvV (ORCPT ); Fri, 8 Dec 2023 16:51:21 -0500 Received: from mail-wm1-x32c.google.com (mail-wm1-x32c.google.com [IPv6:2a00:1450:4864:20::32c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3F5CCEA; Fri, 8 Dec 2023 13:51:27 -0800 (PST) Received: by mail-wm1-x32c.google.com with SMTP id 5b1f17b1804b1-40c19467a63so28429865e9.3; Fri, 08 Dec 2023 13:51:27 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1702072286; x=1702677086; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=aDn8NwTCQ+8/XvF68whD6iZE3c1B6URP/KepTuq9faE=; b=mEI3bgscaaakSSrpLb8xKYBWGo1GSzbBrw2fppCIbFiYwFrHF53frMSs9c6OR4Icsv HsjXYsNKyWQNRi5rikr5JcaeBm5+r3G6g0IFSnXzEoVNNUxGQxctwF/kWxEQ8HzUyCrQ 0Yh3cXaLAticszPodb4ZisCIS3FQxCEs/cWhkWkylsBd2aYETKo2Ke09q2dIQ1fQtQQh OGLrPCBlZGKQ/QBTXXmBZBiTqEvxYPXAo9Ef3k/ErGvun2hwRM3i2bb/SAXg4fHB94Ob jmsaGMMgw+Tjy9tHeYzk8UB/GWNT4YDZiTAvkDjTeYtnVptllmv+qQaOdEWv/qKyvY9k /+Yw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1702072286; x=1702677086; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=aDn8NwTCQ+8/XvF68whD6iZE3c1B6URP/KepTuq9faE=; b=FmGzmSmPdQuyLO0v0lRbPpb1VZPZMat1qyJiNcMXAI+7HxLy6a3r6mk2R8gO6mxfjG THAMXtc89gMtKU5pV77N0pSI2jVwPKnE769Eb0o57gWcuuU9NaEH3TvWMbcuRhxFeFrQ 4KcXGfCbhp17ei8tq6gMzJWd/VEsjUecOIpBjI5Zvpp2ki5eIJahkeJ52Wtf9idCHF02 5lUXnF04cS4LyM91v4eqp3PGrCWFpzAPM8fU61Gld9QujO7lfNiC5AaIvAFEgiYCdyaf JVREj9963pBnEJrVIQy+Z1Xum0W8MOkHZb+2ozCpEobKhCQDBQ+l4Nz0NdDruiseMsNF ragw== X-Gm-Message-State: AOJu0YwGboVXkv5ZR6W9kfBrOzy0TCMTXtBhZuKRCRBeJInHSWtxRsou jJcvOoE3ohqFURKG8DscIFs= X-Google-Smtp-Source: AGHT+IG4SG7UtNtnsAVP+QwJRQm/GC1qLdmy76z4efwgZoC4am/jhFYqbTF6krX1YXtOoQcvZ6GnUw== X-Received: by 2002:a05:600c:2249:b0:40c:1ebd:11c4 with SMTP id a9-20020a05600c224900b0040c1ebd11c4mr328867wmm.15.1702072285316; Fri, 08 Dec 2023 13:51:25 -0800 (PST) Received: from nz.home ([2a00:23c8:a613:101:5d8:ec3b:9abe:2b3d]) by smtp.gmail.com with ESMTPSA id p14-20020a05600c358e00b0040c37c4c229sm1660581wmq.14.2023.12.08.13.51.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 08 Dec 2023 13:51:24 -0800 (PST) Received: by nz.home (Postfix, from userid 1000) id 1E2A413AA9C8D3; Fri, 8 Dec 2023 21:51:24 +0000 (GMT) From: Sergei Trofimovich To: bpf@vger.kernel.org, Eduard Zingerman Cc: linux-kernel@vger.kernel.org, Sergei Trofimovich , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa Subject: [PATCH v2] libbpf: add pr_warn() for EINVAL cases in linker_sanity_check_elf Date: Fri, 8 Dec 2023 21:51:00 +0000 Message-ID: <20231208215100.435876-1-slyich@gmail.com> X-Mailer: git-send-email 2.42.0 In-Reply-To: <159e94e7ce82e9432bd2bba0141c8feab0a9a2e6.camel@gmail.com> References: <159e94e7ce82e9432bd2bba0141c8feab0a9a2e6.camel@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Before the change on `i686-linux` `systemd` build failed as: $ bpftool gen object src/core/bpf/socket_bind/socket-bind.bpf.o src/cor= e/bpf/socket_bind/socket-bind.bpf.unstripped.o Error: failed to link 'src/core/bpf/socket_bind/socket-bind.bpf.unstrip= ped.o': Invalid argument (22) After the change it fails as: $ bpftool gen object src/core/bpf/socket_bind/socket-bind.bpf.o src/cor= e/bpf/socket_bind/socket-bind.bpf.unstripped.o libbpf: ELF section #9 has inconsistent alignment addr=3D8 !=3D d=3D4 i= n src/core/bpf/socket_bind/socket-bind.bpf.unstripped.o Error: failed to link 'src/core/bpf/socket_bind/socket-bind.bpf.unstrip= ped.o': Invalid argument (22) Now it's slightly easier to figure out what is wrong with an ELF file. CC: Alexei Starovoitov CC: Daniel Borkmann CC: Andrii Nakryiko CC: Martin KaFai Lau CC: Song Liu CC: Yonghong Song CC: John Fastabend CC: KP Singh CC: Stanislav Fomichev CC: Hao Luo CC: Jiri Olsa CC: Eduard Zingerman CC: bpf@vger.kernel.org Signed-off-by: Sergei Trofimovich Acked-by: Eduard Zingerman --- tools/lib/bpf/linker.c | 24 ++++++++++++++++++++---- 1 file changed, 20 insertions(+), 4 deletions(-) Change since v1: Following Eduard's suggestion added one extra pr_warn() call around section alignment and added compared values into warning messages. diff --git a/tools/lib/bpf/linker.c b/tools/lib/bpf/linker.c index 5ced96d99f8c..52a2901e8bd0 100644 --- a/tools/lib/bpf/linker.c +++ b/tools/lib/bpf/linker.c @@ -719,13 +719,25 @@ static int linker_sanity_check_elf(struct src_obj *ob= j) return -EINVAL; } =20 - if (sec->shdr->sh_addralign && !is_pow_of_2(sec->shdr->sh_addralign)) + if (sec->shdr->sh_addralign && !is_pow_of_2(sec->shdr->sh_addralign)) { + pr_warn("ELF section #%zu alignment %llu is non pow-of-2 alignment in %= s\n", + sec->sec_idx, (long long unsigned)sec->shdr->sh_addralign, + obj->filename); return -EINVAL; - if (sec->shdr->sh_addralign !=3D sec->data->d_align) + } + if (sec->shdr->sh_addralign !=3D sec->data->d_align) { + pr_warn("ELF section #%zu has inconsistent alignment addr=3D%llu !=3D d= =3D%llu in %s\n", + sec->sec_idx, (long long unsigned)sec->shdr->sh_addralign, + (long long unsigned)sec->data->d_align, obj->filename); return -EINVAL; + } =20 - if (sec->shdr->sh_size !=3D sec->data->d_size) + if (sec->shdr->sh_size !=3D sec->data->d_size) { + pr_warn("ELF section #%zu has inconsistent section size sh=3D%llu !=3D = d=3D%llu in %s\n", + sec->sec_idx, (long long unsigned)sec->shdr->sh_size, + (long long unsigned)sec->data->d_size, obj->filename); return -EINVAL; + } =20 switch (sec->shdr->sh_type) { case SHT_SYMTAB: @@ -737,8 +749,12 @@ static int linker_sanity_check_elf(struct src_obj *obj) break; case SHT_PROGBITS: if (sec->shdr->sh_flags & SHF_EXECINSTR) { - if (sec->shdr->sh_size % sizeof(struct bpf_insn) !=3D 0) + if (sec->shdr->sh_size % sizeof(struct bpf_insn) !=3D 0) { + pr_warn("ELF section #%zu has unexpected size alignment %llu in %s\n", + sec->sec_idx, (long long unsigned)sec->shdr->sh_size, + obj->filename); return -EINVAL; + } } break; case SHT_NOBITS: --=20 2.42.0