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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CDFADCD613C for ; Mon, 9 Oct 2023 21:41:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1378731AbjJIVlw (ORCPT ); Mon, 9 Oct 2023 17:41:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58372 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1377177AbjJIVlu (ORCPT ); Mon, 9 Oct 2023 17:41:50 -0400 Received: from mail-yw1-x1149.google.com (mail-yw1-x1149.google.com [IPv6:2607:f8b0:4864:20::1149]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BE8399D for ; Mon, 9 Oct 2023 14:41:49 -0700 (PDT) Received: by mail-yw1-x1149.google.com with SMTP id 00721157ae682-59f7d4bbfc7so79694827b3.3 for ; Mon, 09 Oct 2023 14:41:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1696887709; x=1697492509; darn=vger.kernel.org; h=to:from:subject:mime-version:message-id:date:from:to:cc:subject :date:message-id:reply-to; bh=lab+IK477apFFSLjWykol92FbgsP0NP2xQdCcWnRJJc=; b=K9pUEWqiZcinseww7WXpCz4QMMx9aZ93ON8J8Zehe6VG/FlMFMR2pt4+bl+gkmqqja CkUF29uEXeh7Bkp5mZiY0Yu8Pjn1MvYJXhFBkz2Lr1Dc2CeRMApnbXsYr9NtADkT1zkq 5c3oJeepAPSSH7zNZ1yxx0tDPe/OxtjcEvK9uiE35oQkClq82L5NKj50h5BzhfGAc+wM kTJFu/28gIlbdZTu9vSrXoC7e+HmTJxrlFri0g7edr4bx5mFiKWPGPlPiDG1CjRZB0Ki lis5nHOwXX0HrT+pMykJCvBIkbd41waXUY2mhJMO4+XrnIh7M6vhn7rZyG9nSe7vI0UB NIEg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1696887709; x=1697492509; h=to:from:subject:mime-version:message-id:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=lab+IK477apFFSLjWykol92FbgsP0NP2xQdCcWnRJJc=; b=gC3+MRgpu5EoKSth4uL1uljioH7IcpL/aJoDWwL/ATNPeBRjEJnKjaR/nEHL35KrbU y3eTIgOT07ry3y8Fd3pHNBcCsQy+cENg1lIq3f7NnjdxCfGbPZRukI6vY4aJ789X1Yaf Z2Qopp7lgVsX7LZpk4lvN+LtFPyqAwAQkD6FuKC4GpKrCQkSUu9zC+yoII4/e6WKCdeL mqD6wBWB3Mar/GdybykNYfGiwBOJ838MPdtWWrqJu52YbPI8dLrrEUUQa8bioopJFfnF YM2qyWHdkvjjI1jm25ziTsN2QO+LZuO7uYiKPFVV3ijb09bFkKxh4Dm6tX8VetvsXq6/ W8Lg== X-Gm-Message-State: AOJu0YyWLSNxO5KZZYV0ABy/A6vF4zwEvm7QXIfUSaQG6WZ89Y5GZtAR ExFMt9VH0wBy1Hs/D1P9x+LHHxf/buS+ X-Google-Smtp-Source: AGHT+IGzh2MJLvBdA0jC3P3CQdImlAG66wNFPAdO21hsujTQLSbMPvwXgNC2udPrZmYhI8dlvuLIWcUb34dF X-Received: from irogers.svl.corp.google.com ([2620:15c:2a3:200:ac4a:9b94:7158:3f4e]) (user=irogers job=sendgmr) by 2002:a81:a849:0:b0:577:619e:d3c9 with SMTP id f70-20020a81a849000000b00577619ed3c9mr344168ywh.10.1696887708906; Mon, 09 Oct 2023 14:41:48 -0700 (PDT) Date: Mon, 9 Oct 2023 14:41:41 -0700 Message-Id: <20231009214143.349978-1-irogers@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.42.0.609.gbb76f46606-goog Subject: [PATCH v1 1/3] 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 , Leo Yan , Ravi Bangoria , German Gomez , Artem Savkov , Andi Kleen , Kan Liang , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Running perf top with address sanitizer and "--call-graph=lbr" 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); } - /* Add LBR ip from first entries.to */ - ip = entries[0].to; - flags = &entries[0].flags; - *branch_from = entries[0].from; - err = 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 = entries[0].to; + flags = &entries[0].flags; + *branch_from = entries[0].from; + err = add_callchain_ip(thread, cursor, parent, + root_al, &cpumode, ip, + true, flags, NULL, + *branch_from); + if (err) + return err; + } return 0; } -- 2.42.0.609.gbb76f46606-goog