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 97ADECA0ECD for ; Thu, 14 Sep 2023 04:42:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231181AbjINEms (ORCPT ); Thu, 14 Sep 2023 00:42:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38690 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231972AbjINEmr (ORCPT ); Thu, 14 Sep 2023 00:42:47 -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 7097E198B for ; Wed, 13 Sep 2023 21:42:42 -0700 (PDT) Received: by mail-yw1-x1149.google.com with SMTP id 00721157ae682-58fc7afa4beso8351367b3.2 for ; Wed, 13 Sep 2023 21:42:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1694666561; x=1695271361; darn=vger.kernel.org; h=to:from:subject:mime-version:message-id:date:from:to:cc:subject :date:message-id:reply-to; bh=1HUitirtv3MlkOjFE/+m21aYPcp7zNtjHMHmwF7qUUE=; b=4FaOT++M4mmbE8qmGg8bcDu+h0LN9B+B2pvwcCdu+D03RNGyM48D5Dc17pnj5WMQp5 c4Xq0wmUu2kQtrHLEvtmdFFNiz+qjfDnE5EKLIWBYR2V+WofBdbYOboS7o+y3ftz/5mS nqBMJKMOBueGIraN6Z/8TGjIOuVJVqSn81m07W22Mmz3uRWFf4TN1Hd3I2G6Kiv0yfmq SFy9bjhq3S28s8jtYYGwKbfshamAPrsJy6uXuygz393MWzwvdsB6PtsoiEZtEa7SI9KF lm7TLr2+lxsVrhRcRr3+uxd7g5M6RTQCdnfoHjJ9HLgKJqA+bq+gVXEmbdPI1xLyPZse IPCw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1694666561; x=1695271361; h=to:from:subject:mime-version:message-id:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=1HUitirtv3MlkOjFE/+m21aYPcp7zNtjHMHmwF7qUUE=; b=ksH9p0GH+HezcBRXkgT0LinQ6O0YuEmj/Vn3PzaXdTbSifkvpe+azWieiWghvKyAUw R8psX05Sm3aVMBqX0IJRZxlXxVSN2Rn08VDUQiAl+2QZU2rceL9BMZVkc72NIygDpw// QYDCbfos93bAoqfe5M55+sUH62nvUiuFXL2MtWyx+mjvjEdE192J2f/A7BlVNmfvitCH E6b+YNi4Kec/jqNSm3EaL8y/QPXMhPt0+mV2GiN9IxbWzeNJGtL7hN1vnipBiGtPD8wc /Btp3EBtGjLVTvIpWNyaurLgE/n6LRN24CZFtHDBQVY9zVZ1piPCbycqIJRLGdQ1xyGK rNdg== X-Gm-Message-State: AOJu0YzrIz42jlsDRaDsA2vBtd4r/uvTkWJezX3JzSZ3Its5Wohaalbl VIsNkf/C4h/QQKSrJtCrYY+lV4Ayktu5 X-Google-Smtp-Source: AGHT+IEN/077fAkp5yMboSyz7Pt4O7f+pFXS5/PlYDxMWe3T6O8biy09CF1qTv4xeXl/Vyd19SfmjQeV8EC7 X-Received: from irogers.svl.corp.google.com ([2620:15c:2a3:200:7612:4bb6:bcf1:779c]) (user=irogers job=sendgmr) by 2002:a25:26c4:0:b0:d47:5cc3:9917 with SMTP id m187-20020a2526c4000000b00d475cc39917mr96593ybm.9.1694666561603; Wed, 13 Sep 2023 21:42:41 -0700 (PDT) Date: Wed, 13 Sep 2023 21:42:32 -0700 Message-Id: <20230914044233.1550195-1-irogers@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.42.0.459.ge4e396fd5e-goog Subject: [PATCH v1] perf symbol: Avoid an undefined behavior warning From: Ian Rogers To: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Ian Rogers , Adrian Hunter , James Clark , 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-perf-users@vger.kernel.org The node (nd) may be NULL and pointer arithmetic on NULL is undefined behavior. Move the computation of next below the NULL check on the node. Signed-off-by: Ian Rogers --- tools/perf/util/symbol.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index 3f36675b7c8f..5b54d2639df4 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -202,11 +202,10 @@ void symbols__fixup_duplicate(struct rb_root_cached *symbols) curr = rb_entry(nd, struct symbol, rb_node); again: nd = rb_next(&curr->rb_node); - next = rb_entry(nd, struct symbol, rb_node); - if (!nd) break; + next = rb_entry(nd, struct symbol, rb_node); if (curr->start != next->start) continue; -- 2.42.0.459.ge4e396fd5e-goog