From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_RED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BC520C433DB for ; Mon, 28 Dec 2020 23:17:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 801CC223C8 for ; Mon, 28 Dec 2020 23:17:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730280AbgL1Wzo (ORCPT ); Mon, 28 Dec 2020 17:55:44 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55508 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729334AbgL1Tsg (ORCPT ); Mon, 28 Dec 2020 14:48:36 -0500 Received: from mail-yb1-xb2d.google.com (mail-yb1-xb2d.google.com [IPv6:2607:f8b0:4864:20::b2d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 83981C0613D6; Mon, 28 Dec 2020 11:47:56 -0800 (PST) Received: by mail-yb1-xb2d.google.com with SMTP id v67so10616545ybi.1; Mon, 28 Dec 2020 11:47:56 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=YJxWnY3S6EVUF/zhRpyGnoCte1dOf0xelEIF09j73nE=; b=RCZifI1lUFBuAuSjA+FJzk6ncmyhWCzRBCsChj43TCMv3dLeHpj8+LhbvI+z1vkPEN iQw2b2k33JsygORAbwXGo8lkjxUjPgjuYLD19MEUO/ityxb4RFaK9Pty/F8UX02V0XBu W/TJhGZlTTHa9MT8AY8cHtL+Dqe4Ye44juGhW1PKQh+9HyyW1dGYvqHVKhpTFcYVBFId uwLi8Y1oQVK/OaeFy3D29tgEoVwXD1RQfBpN/FVYSVID0V86YMuGReq0cy3WrCByKOV7 mHiy9h/PR9GzAr+aO6zRoASfPuse+XzrIobf1xDvyyzklQNzgLP7LQdWF/hBkY1lxlZL eKJQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=YJxWnY3S6EVUF/zhRpyGnoCte1dOf0xelEIF09j73nE=; b=QpnTUE7nuUai9BqlnsTEjfIPNX4F3Zey7kf07h7C//b8zOJcXXr8v7NWzwJjUc9xzM ZGwt2whqNCuXrzsRwu8pIuGIXC5/ciEo54nnDBu2qjJD8cake9oYZL0CG5n/u7vZom5E nhu/PaVjN8AsjFkkCgwUA0Jxl8AJO5lR3pmIzZ7Qpn2mrk5++5iGdKVcJsEUuWbTlWvo ZCc6lWcb3bVjor/sr+SbzYZeQ/GXsRaH5xdo3UebtcgO+i9fO2I5tcjt1XF2yG2j9tH+ OYXYf0gZJgcKN0hGeL/ww/uYx1z78tRCFoBir2IDkZvlUrgnLlsb2MwW7iaAZJbtoRj4 m9Eg== X-Gm-Message-State: AOAM531qJrHrzjHpsflvQ+3Y0IRk9LGrPD6T0iHMDcoxP0Zo9mpPfA3r WIrTP7HgwKSYq8rtLJaO9z9SDHd/PMcPCg4lJhg= X-Google-Smtp-Source: ABdhPJyshbe47AaEyX0gpX5HJt+JCQjfxlMQHpk/yBV2w/ItPm5nzLQWre/A/IVCufs4uHzvsjmsRVnbiwyV4D5qfoc= X-Received: by 2002:a25:2c4c:: with SMTP id s73mr48282328ybs.230.1609184875632; Mon, 28 Dec 2020 11:47:55 -0800 (PST) MIME-Version: 1.0 References: <20201228124937.240114599@linuxfoundation.org> <20201228124942.316302285@linuxfoundation.org> In-Reply-To: From: Andrii Nakryiko Date: Mon, 28 Dec 2020 11:47:44 -0800 Message-ID: Subject: Re: [PATCH 5.4 106/453] libbpf: Fix BTF data layout checks and allow empty BTF To: Naresh Kamboju Cc: Greg Kroah-Hartman , open list , linux-stable , Andrii Nakryiko , Alexei Starovoitov , Sasha Levin Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Dec 28, 2020 at 7:49 AM Naresh Kamboju wrote: > > Perf build failed on stable-rc 5.4 branch due to this patch. > > On Mon, 28 Dec 2020 at 19:15, Greg Kroah-Hartman > wrote: > > > > From: Andrii Nakryiko > > > > [ Upstream commit d8123624506cd62730c9cd9c7672c698e462703d ] > > > > Make data section layout checks stricter, disallowing overlap of types and > > strings data. > > > > Additionally, allow BTFs with no type data. There is nothing inherently wrong > > with having BTF with no types (put potentially with some strings). This could > > be a situation with kernel module BTFs, if module doesn't introduce any new > > type information. > > > > Also fix invalid offset alignment check for btf->hdr->type_off. > > > > Fixes: 8a138aed4a80 ("bpf: btf: Add BTF support to libbpf") > > Signed-off-by: Andrii Nakryiko > > Signed-off-by: Alexei Starovoitov > > Link: https://lore.kernel.org/bpf/20201105043402.2530976-8-andrii@kernel.org > > Signed-off-by: Sasha Levin > > --- > > tools/lib/bpf/btf.c | 16 ++++++---------- > > 1 file changed, 6 insertions(+), 10 deletions(-) > > > > diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c > > index d606a358480da..3380aadb74655 100644 > > --- a/tools/lib/bpf/btf.c > > +++ b/tools/lib/bpf/btf.c > > @@ -100,22 +100,18 @@ static int btf_parse_hdr(struct btf *btf) > > return -EINVAL; > > } > > > > - if (meta_left < hdr->type_off) { > > - pr_debug("Invalid BTF type section offset:%u\n", hdr->type_off); > > + if (meta_left < hdr->str_off + hdr->str_len) { > > + pr_debug("Invalid BTF total size:%u\n", btf->raw_size); > > In file included from btf.c:17:0: > btf.c: In function 'btf_parse_hdr': > btf.c:104:48: error: 'struct btf' has no member named 'raw_size'; did > you mean 'data_size'? > pr_debug("Invalid BTF total size:%u\n", btf->raw_size); > ^ > libbpf_internal.h:59:40: note: in definition of macro '__pr' > libbpf_print(level, "libbpf: " fmt, ##__VA_ARGS__); \ > ^~~~~~~~~~~ > btf.c:104:3: note: in expansion of macro 'pr_debug' > pr_debug("Invalid BTF total size:%u\n", btf->raw_size); > ^~~~~~~~ > This patch fixes the bug introduced back in 8a138aed4a80 ("bpf: btf: Add BTF support to libbpf"), but a bunch of other refactorings happened since then, adding/renaming struct btf internals. The fix here is not that critical, so it's probably best to just drop this patch from the stable, if possible. Would it be ok, Greg? > full build log link, > https://ci.linaro.org/view/lkft/job/openembedded-lkft-linux-stable-rc-5.4/DISTRO=lkft,MACHINE=intel-corei7-64,label=docker-buster-lkft/346/consoleText > > -- > Linaro LKFT > https://lkft.linaro.org