From nobody Fri Dec 19 04:01:53 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 7DE43CDB46E for ; Thu, 12 Oct 2023 06:24:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1377445AbjJLGYM (ORCPT ); Thu, 12 Oct 2023 02:24:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49308 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1377424AbjJLGYJ (ORCPT ); Thu, 12 Oct 2023 02:24:09 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E8A4AC4 for ; Wed, 11 Oct 2023 23:24:06 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id 3f1490d57ef6-d9a3e0f8872so850702276.0 for ; Wed, 11 Oct 2023 23:24:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1697091846; x=1697696646; darn=vger.kernel.org; h=to:from:subject:references:mime-version:message-id:in-reply-to:date :from:to:cc:subject:date:message-id:reply-to; bh=lab+IK477apFFSLjWykol92FbgsP0NP2xQdCcWnRJJc=; b=HHqg13XMM6x5HB+wzaqVWPqgMBahLq/RY1RmgEc2/TmpFv4ho4MxYKvra36JQDWIf0 PsrGWjiBAuiToHNVg8at7GslsuGc9hywA1NRAZHS79TVEmrkOFYFU3/osWIkZKIDS1tb VUfskzb4hwHd1ULwHXp674ukE7Kg6ids2LsZZybMBe+86SiIk5CD06mb2zn1kwb7128N snnnO1QpY4sve61Yv6HhfLVVKykoQVXfAnDvu74tTlPeIsrU37It0HHQ2cNio8dE4LtR X23KzD9P3ZLNtNc79cq+Ac5ANJpjIhxggQkilLvEHXNIYGfVNPYLhZ2z3vlU9RSYnHRE Q+tw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697091846; x=1697696646; h=to:from:subject:references:mime-version:message-id:in-reply-to:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=lab+IK477apFFSLjWykol92FbgsP0NP2xQdCcWnRJJc=; b=sG/l+WgVWDyAO/wM4Jgz1jW56jI2e/5+biRPbnY8sa8Crn1kkN6LbnUyoniTgsqZn1 yu11cyBU2wa0yOSyPgvjDmt9CII2J6hIAoKSvYQz0CoqNnErDzX6cq4VyYhLZMH8bF50 P/bPzdMSYsVrMEUu6CZNOuODMe9lvRuvYJHc83wZnAtLrKj8AyTCtk+gNfdRgA4ieehZ +mGch9nHav4BDPtrl34umOGS0BKlYHmYUopprtnSXH7Uo+QkeM6Cw0KaX0Ry8YdR7UA9 6b7q52P3YEZnW3zntxa7gjzAAjxmVkGAaZelEbN/9+QZ7Rp8Zup9rfCCCslufu88gQs6 r37g== X-Gm-Message-State: AOJu0Yx2Do7LG0dAedS5jfD5X5zeyX7AS0aFzTwtvAY5Q5C8hQ23FVfZ ETub/ET901oBfRtHriCgDcISldrq7Iag X-Google-Smtp-Source: AGHT+IHnIAXcUzihWQojvyw8UJR3bPVrgp/MTrrJXWebCRY8gHHYkJpjznxCH58B5pkwT3b1yo+r8GOb/Yxd X-Received: from irogers.svl.corp.google.com ([2620:15c:2a3:200:7be5:14d2:880b:c5c9]) (user=irogers job=sendgmr) by 2002:a25:2fd7:0:b0:d9a:6419:f8c2 with SMTP id v206-20020a252fd7000000b00d9a6419f8c2mr121947ybv.2.1697091846096; Wed, 11 Oct 2023 23:24:06 -0700 (PDT) Date: Wed, 11 Oct 2023 23:23:47 -0700 In-Reply-To: <20231012062359.1616786-1-irogers@google.com> Message-Id: <20231012062359.1616786-2-irogers@google.com> Mime-Version: 1.0 References: <20231012062359.1616786-1-irogers@google.com> X-Mailer: git-send-email 2.42.0.609.gbb76f46606-goog Subject: [PATCH v2 01/13] perf machine: Avoid out of bounds LBR memory read From: Ian Rogers To: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Ian Rogers , Adrian Hunter , Nick Terrell , Kan Liang , Song Liu , Sandipan Das , Anshuman Khandual , James Clark , Liam Howlett , Miguel Ojeda , Leo Yan , German Gomez , Ravi Bangoria , Artem Savkov , Athira Rajeev , Andi Kleen , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, bpf@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Running perf top with address sanitizer and "--call-graph=3Dlbr" fails due to reading sample 0 when no samples exist. Add a guard to prevent this. Fixes: e2b23483eb1d ("perf machine: Factor out lbr_callchain_add_lbr_ip()") Signed-off-by: Ian Rogers --- tools/perf/util/machine.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index addfae2f63ef..e0e2c4a943e4 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -2622,16 +2622,18 @@ static int lbr_callchain_add_lbr_ip(struct thread *= thread, save_lbr_cursor_node(thread, cursor, i); } =20 - /* Add LBR ip from first entries.to */ - ip =3D entries[0].to; - flags =3D &entries[0].flags; - *branch_from =3D entries[0].from; - err =3D add_callchain_ip(thread, cursor, parent, - root_al, &cpumode, ip, - true, flags, NULL, - *branch_from); - if (err) - return err; + if (lbr_nr > 0) { + /* Add LBR ip from first entries.to */ + ip =3D entries[0].to; + flags =3D &entries[0].flags; + *branch_from =3D entries[0].from; + err =3D add_callchain_ip(thread, cursor, parent, + root_al, &cpumode, ip, + true, flags, NULL, + *branch_from); + if (err) + return err; + } =20 return 0; } --=20 2.42.0.609.gbb76f46606-goog