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=-6.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=ham 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 532F2C83000 for ; Wed, 29 Apr 2020 17:45:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2E26022208 for ; Wed, 29 Apr 2020 17:45:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="JZBa6d/p" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727100AbgD2RpO (ORCPT ); Wed, 29 Apr 2020 13:45:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35736 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726423AbgD2RpN (ORCPT ); Wed, 29 Apr 2020 13:45:13 -0400 Received: from mail-qt1-x841.google.com (mail-qt1-x841.google.com [IPv6:2607:f8b0:4864:20::841]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6D58BC03C1AE for ; Wed, 29 Apr 2020 10:45:13 -0700 (PDT) Received: by mail-qt1-x841.google.com with SMTP id o10so2603336qtr.6 for ; Wed, 29 Apr 2020 10:45:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:date:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=pNOTE8azPZYAJ5CF5910AMNX6/C9i6fDy25Mv94mhz4=; b=JZBa6d/pK58LBnmNrQVv70YqrHdZMC/mIq6EFekSKHVk4QKYcZ9DKsR7IFaX1ezQqF rxBUMHkcpM+JER7TGAkH4bgsF/ycLewrICblSU5GKaC+Jd2tMBCToXR0sOwjdTQpAERS U3lrgaCJ3DK4GzLnmD7bGyCaI7h3SUPqnS+sRSlL6iGV1qg6nzmqNH6emWvuBCEEBKC5 UnNpmMXT7oCJTNY52yc6qL8tN6jMhE0ILf8V/9af3EaJEYqVBYy2aGMBRI9pOpXMqZ2C CPmvTyXystgMU8PWvL4XyLt6VupcJ8v/18U6sKfYEOSDt+Ilhn14XXzkgZ1rJyicvXsS ew3A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:date:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=pNOTE8azPZYAJ5CF5910AMNX6/C9i6fDy25Mv94mhz4=; b=A7/qhhMEMUx+SCJc7BW1VOgTOCGzYQ0cZgGfYAFEqH24WV2po5D5qQNq57xNhKpm4L jRv0QWirqOk3+0SBGuqHAOixV7FXzGl1QWTzLXmIcDevZpw4girToxPfcryEppzM8tVp VQDqnMQDA3q1Mb3KeT8bUs+SAr/+c54lghS3o8Pg62ohqdJuxVt+MdFqD+CEeVJ1/8l6 XwD4Z0xMYyFAUHaOAXQ8NcNxZscN2oDxtCHaL/kH+KNN/EOWE5cQzMTL01ccpxz821yH GfqyIErP2yQewJB5YKMCl+0cnCsqYZnHjFqrNEm6mhQNDrH2IGXzW1Fzve1dJjlA/w/F InMw== X-Gm-Message-State: AGi0Puavu04f8jWKtWk+N3ohGNiQ2PmhaVyBDy+nCjWyyB1wUb3oqn1l DG+8DpHQPHh+4VOoQYcTlfk= X-Google-Smtp-Source: APiQypJTivveO3QdfW4n4Eg7AgkLY8zCK/ZzTUznwp2YMjpvJp8BoeOA1PeXPUKLQJqR9mLrycspKQ== X-Received: by 2002:ac8:189c:: with SMTP id s28mr35452140qtj.65.1588182311757; Wed, 29 Apr 2020 10:45:11 -0700 (PDT) Received: from quaco.ghostprotocols.net ([179.97.37.151]) by smtp.gmail.com with ESMTPSA id u7sm15862418qkj.51.2020.04.29.10.45.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 29 Apr 2020 10:45:10 -0700 (PDT) From: Arnaldo Carvalho de Melo X-Google-Original-From: Arnaldo Carvalho de Melo Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id E7226409A3; Wed, 29 Apr 2020 14:45:08 -0300 (-03) Date: Wed, 29 Apr 2020 14:45:08 -0300 To: Ian Rogers Cc: Peter Zijlstra , Ingo Molnar , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , LKML , clang-built-linux , Stephane Eranian Subject: Re: [PATCH v2] perf mem2node: avoid double free related to realloc Message-ID: <20200429174508.GC30487@kernel.org> References: <20200320182347.87675-1-irogers@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Url: http://acmel.wordpress.com Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Em Wed, Apr 29, 2020 at 10:40:06AM -0700, Ian Rogers escreveu: > Ping. This is missing an Acked-by: > v2 addressed Jiri's review comments: > https://lore.kernel.org/lkml/20200315093013.GC492969@krava/ Jiri? > Thanks, > Ian > > > On Fri, Mar 20, 2020 at 11:23 AM Ian Rogers wrote: > > > > Realloc of size zero is a free not an error, avoid this causing a double > > free. Caught by clang's address sanitizer: > > > > ==2634==ERROR: AddressSanitizer: attempting double-free on 0x6020000015f0 in thread T0: > > #0 0x5649659297fd in free llvm/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:123:3 > > #1 0x5649659e9251 in __zfree tools/lib/zalloc.c:13:2 > > #2 0x564965c0f92c in mem2node__exit tools/perf/util/mem2node.c:114:2 > > #3 0x564965a08b4c in perf_c2c__report tools/perf/builtin-c2c.c:2867:2 > > #4 0x564965a0616a in cmd_c2c tools/perf/builtin-c2c.c:2989:10 > > #5 0x564965944348 in run_builtin tools/perf/perf.c:312:11 > > #6 0x564965943235 in handle_internal_command tools/perf/perf.c:364:8 > > #7 0x5649659440c4 in run_argv tools/perf/perf.c:408:2 > > #8 0x564965942e41 in main tools/perf/perf.c:538:3 > > > > 0x6020000015f0 is located 0 bytes inside of 1-byte region [0x6020000015f0,0x6020000015f1) > > freed by thread T0 here: > > #0 0x564965929da3 in realloc third_party/llvm/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3 > > #1 0x564965c0f55e in mem2node__init tools/perf/util/mem2node.c:97:16 > > #2 0x564965a08956 in perf_c2c__report tools/perf/builtin-c2c.c:2803:8 > > #3 0x564965a0616a in cmd_c2c tools/perf/builtin-c2c.c:2989:10 > > #4 0x564965944348 in run_builtin tools/perf/perf.c:312:11 > > #5 0x564965943235 in handle_internal_command tools/perf/perf.c:364:8 > > #6 0x5649659440c4 in run_argv tools/perf/perf.c:408:2 > > #7 0x564965942e41 in main tools/perf/perf.c:538:3 > > > > previously allocated by thread T0 here: > > #0 0x564965929c42 in calloc third_party/llvm/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:154:3 > > #1 0x5649659e9220 in zalloc tools/lib/zalloc.c:8:9 > > #2 0x564965c0f32d in mem2node__init tools/perf/util/mem2node.c:61:12 > > #3 0x564965a08956 in perf_c2c__report tools/perf/builtin-c2c.c:2803:8 > > #4 0x564965a0616a in cmd_c2c tools/perf/builtin-c2c.c:2989:10 > > #5 0x564965944348 in run_builtin tools/perf/perf.c:312:11 > > #6 0x564965943235 in handle_internal_command tools/perf/perf.c:364:8 > > #7 0x5649659440c4 in run_argv tools/perf/perf.c:408:2 > > #8 0x564965942e41 in main tools/perf/perf.c:538:3 > > > > v2: add a WARN_ON_ONCE when the free condition arises. > > > > Signed-off-by: Ian Rogers > > --- > > tools/perf/util/mem2node.c | 3 ++- > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > diff --git a/tools/perf/util/mem2node.c b/tools/perf/util/mem2node.c > > index 797d86a1ab09..c84f5841c7ab 100644 > > --- a/tools/perf/util/mem2node.c > > +++ b/tools/perf/util/mem2node.c > > @@ -1,5 +1,6 @@ > > #include > > #include > > +#include > > #include > > #include > > #include > > @@ -95,7 +96,7 @@ int mem2node__init(struct mem2node *map, struct perf_env *env) > > > > /* Cut unused entries, due to merging. */ > > tmp_entries = realloc(entries, sizeof(*entries) * j); > > - if (tmp_entries) > > + if (tmp_entries || WARN_ON_ONCE(j == 0)) > > entries = tmp_entries; > > > > for (i = 0; i < j; i++) { > > -- > > 2.25.1.696.g5e7596f4ac-goog > > -- - Arnaldo