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=-10.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 1F1C6C2D0A8 for ; Sat, 26 Sep 2020 13:10:30 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 932E2221ED for ; Sat, 26 Sep 2020 13:10:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=web.de header.i=@web.de header.b="Rt4ruXTx" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 932E2221ED Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=web.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 82FFF6B005C; Sat, 26 Sep 2020 09:10:28 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 7E0086B0062; Sat, 26 Sep 2020 09:10:28 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6A8C48E0001; Sat, 26 Sep 2020 09:10:28 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0174.hostedemail.com [216.40.44.174]) by kanga.kvack.org (Postfix) with ESMTP id 52D036B005C for ; Sat, 26 Sep 2020 09:10:28 -0400 (EDT) Received: from smtpin04.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 120C7282B for ; Sat, 26 Sep 2020 13:10:28 +0000 (UTC) X-FDA: 77305246536.04.legs67_0d0dbc027170 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin04.hostedemail.com (Postfix) with ESMTP id E6FBE800C8BA for ; Sat, 26 Sep 2020 13:10:27 +0000 (UTC) X-HE-Tag: legs67_0d0dbc027170 X-Filterd-Recvd-Size: 7704 Received: from mout.web.de (mout.web.de [212.227.17.11]) by imf17.hostedemail.com (Postfix) with ESMTP for ; Sat, 26 Sep 2020 13:10:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=web.de; s=dbaedf251592; t=1601125821; bh=iHbUc5ZvTN0KlNysPg/v7V0nJaorORbp1yuylEX96WQ=; h=X-UI-Sender-Class:Subject:To:Cc:References:From:Date:In-Reply-To; b=Rt4ruXTxYLSjkKw4PAGxjezbQUcdpmZobzJU79kZqHnjYvRA8Lx/arwhzQPw4twgo /aXXlzdTmOkbakTX6Y49G7kboIIueNUWYSPwRCNzdWbVcLtV+D11oDZDMiAN8lDCZw egbH/i4e4R/B//nftDO9bD/4p2XN7XX7G/F/QdhY= X-UI-Sender-Class: c548c8c5-30a9-4db5-a2e7-cb6cb037b8f9 Received: from [192.168.1.2] ([78.48.129.137]) by smtp.web.de (mrweb106 [213.165.67.124]) with ESMTPSA (Nemesis) id 1MQgpA-1k7MOx1Z7W-00O8iV; Sat, 26 Sep 2020 15:10:21 +0200 Subject: Re: [PATCH v3] mm/hmm/test: use after free in dmirror_allocate_chunk() To: Dan Carpenter , Dan Williams , =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org, Jason Gunthorpe , Julia Lawall , Ralph Campbell , Wei Yongjun References: <20200926121402.GA7467@kadam> From: Markus Elfring Autocrypt: addr=Markus.Elfring@web.de; prefer-encrypt=mutual; keydata= mQINBFg2+xABEADBJW2hoUoFXVFWTeKbqqif8VjszdMkriilx90WB5c0ddWQX14h6w5bT/A8 +v43YoGpDNyhgA0w9CEhuwfZrE91GocMtjLO67TAc2i2nxMc/FJRDI0OemO4VJ9RwID6ltwt mpVJgXGKkNJ1ey+QOXouzlErVvE2fRh+KXXN1Q7fSmTJlAW9XJYHS3BDHb0uRpymRSX3O+E2 lA87C7R8qAigPDZi6Z7UmwIA83ZMKXQ5stA0lhPyYgQcM7fh7V4ZYhnR0I5/qkUoxKpqaYLp YHBczVP+Zx/zHOM0KQphOMbU7X3c1pmMruoe6ti9uZzqZSLsF+NKXFEPBS665tQr66HJvZvY GMDlntZFAZ6xQvCC1r3MGoxEC1tuEa24vPCC9RZ9wk2sY5Csbva0WwYv3WKRZZBv8eIhGMxs rcpeGShRFyZ/0BYO53wZAPV1pEhGLLxd8eLN/nEWjJE0ejakPC1H/mt5F+yQBJAzz9JzbToU 5jKLu0SugNI18MspJut8AiA1M44CIWrNHXvWsQ+nnBKHDHHYZu7MoXlOmB32ndsfPthR3GSv jN7YD4Ad724H8fhRijmC1+RpuSce7w2JLj5cYj4MlccmNb8YUxsE8brY2WkXQYS8Ivse39MX BE66MQN0r5DQ6oqgoJ4gHIVBUv/ZwgcmUNS5gQkNCFA0dWXznQARAQABtCZNYXJrdXMgRWxm cmluZyA8TWFya3VzLkVsZnJpbmdAd2ViLmRlPokCVAQTAQgAPhYhBHDP0hzibeXjwQ/ITuU9 Figxg9azBQJYNvsQAhsjBQkJZgGABQsJCAcCBhUICQoLAgQWAgMBAh4BAheAAAoJEOU9Figx g9azcyMP/iVihZkZ4VyH3/wlV3nRiXvSreqg+pGPI3c8J6DjP9zvz7QHN35zWM++1yNek7Ar OVXwuKBo18ASlYzZPTFJZwQQdkZSV+atwIzG3US50ZZ4p7VyUuDuQQVVqFlaf6qZOkwHSnk+ CeGxlDz1POSHY17VbJG2CzPuqMfgBtqIU1dODFLpFq4oIAwEOG6fxRa59qbsTLXxyw+PzRaR LIjVOit28raM83Efk07JKow8URb4u1n7k9RGAcnsM5/WMLRbDYjWTx0lJ2WO9zYwPgRykhn2 sOyJVXk9xVESGTwEPbTtfHM+4x0n0gC6GzfTMvwvZ9G6xoM0S4/+lgbaaa9t5tT/PrsvJiob kfqDrPbmSwr2G5mHnSM9M7B+w8odjmQFOwAjfcxoVIHxC4Cl/GAAKsX3KNKTspCHR0Yag78w i8duH/eEd4tB8twcqCi3aCgWoIrhjNS0myusmuA89kAWFFW5z26qNCOefovCx8drdMXQfMYv g5lRk821ZCNBosfRUvcMXoY6lTwHLIDrEfkJQtjxfdTlWQdwr0mM5ye7vd83AManSQwutgpI q+wE8CNY2VN9xAlE7OhcmWXlnAw3MJLW863SXdGlnkA3N+U4BoKQSIToGuXARQ14IMNvfeKX NphLPpUUnUNdfxAHu/S3tPTc/E/oePbHo794dnEm57LuuQINBFg2+xABEADZg/T+4o5qj4cw nd0G5pFy7ACxk28mSrLuva9tyzqPgRZ2bdPiwNXJUvBg1es2u81urekeUvGvnERB/TKekp25 4wU3I2lEhIXj5NVdLc6eU5czZQs4YEZbu1U5iqhhZmKhlLrhLlZv2whLOXRlLwi4jAzXIZAu 76mT813jbczl2dwxFxcT8XRzk9+dwzNTdOg75683uinMgskiiul+dzd6sumdOhRZR7YBT+xC wzfykOgBKnzfFscMwKR0iuHNB+VdEnZw80XGZi4N1ku81DHxmo2HG3icg7CwO1ih2jx8ik0r riIyMhJrTXgR1hF6kQnX7p2mXe6K0s8tQFK0ZZmYpZuGYYsV05OvU8yqrRVL/GYvy4Xgplm3 DuMuC7/A9/BfmxZVEPAS1gW6QQ8vSO4zf60zREKoSNYeiv+tURM2KOEj8tCMZN3k3sNASfoG fMvTvOjT0yzMbJsI1jwLwy5uA2JVdSLoWzBD8awZ2X/eCU9YDZeGuWmxzIHvkuMj8FfX8cK/ 2m437UA877eqmcgiEy/3B7XeHUipOL83gjfq4ETzVmxVswkVvZvR6j2blQVr+MhCZPq83Ota xNB7QptPxJuNRZ49gtT6uQkyGI+2daXqkj/Mot5tKxNKtM1Vbr/3b+AEMA7qLz7QjhgGJcie qp4b0gELjY1Oe9dBAXMiDwARAQABiQI8BBgBCAAmFiEEcM/SHOJt5ePBD8hO5T0WKDGD1rMF Alg2+xACGwwFCQlmAYAACgkQ5T0WKDGD1rOYSw/+P6fYSZjTJDAl9XNfXRjRRyJSfaw6N1pA Ahuu0MIa3djFRuFCrAHUaaFZf5V2iW5xhGnrhDwE1Ksf7tlstSne/G0a+Ef7vhUyeTn6U/0m +/BrsCsBUXhqeNuraGUtaleatQijXfuemUwgB+mE3B0SobE601XLo6MYIhPh8MG32MKO5kOY hB5jzyor7WoN3ETVNQoGgMzPVWIRElwpcXr+yGoTLAOpG7nkAUBBj9n9TPpSdt/npfok9ZfL /Q+ranrxb2Cy4tvOPxeVfR58XveX85ICrW9VHPVq9sJf/a24bMm6+qEg1V/G7u/AM3fM8U2m tdrTqOrfxklZ7beppGKzC1/WLrcr072vrdiN0icyOHQlfWmaPv0pUnW3AwtiMYngT96BevfA qlwaymjPTvH+cTXScnbydfOQW8220JQwykUe+sHRZfAF5TS2YCkQvsyf7vIpSqo/ttDk4+xc Z/wsLiWTgKlih2QYULvW61XU+mWsK8+ZlYUrRMpkauN4CJ5yTpvp+Orcz5KixHQmc5tbkLWf x0n1QFc1xxJhbzN+r9djSGGN/5IBDfUqSANC8cWzHpWaHmSuU3JSAMB/N+yQjIad2ztTckZY pwT6oxng29LzZspTYUEzMz3wK2jQHw+U66qBFk8whA7B2uAU1QdGyPgahLYSOa4XAEGb6wbI FEE= Message-ID: <93514131-71d4-0d32-e05b-224770779226@web.de> Date: Sat, 26 Sep 2020 15:10:11 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.12.0 MIME-Version: 1.0 In-Reply-To: <20200926121402.GA7467@kadam> Content-Type: text/plain; charset=utf-8 Content-Language: en-GB X-Provags-ID: V03:K1:dcnFj38b6VSdQ3xZuYNpZtRZ+lOpGHQJafGF56TKG4EQHe/5n/p W06EbMGfwMAPvVz9qFkjh5bTyfhogsqEFhNeWXdDuOaEQWce50BJtE4nHt/DkOMfHEoJ1vi WpGteMaW42PL+DlY9JArMquNZ0pe3OipcJbYa1nt4VwNqm0a9uyg01MRoyF/l5y7vjxvqqL 2jQPuc+ICbbOg6WoBVDQQ== X-UI-Out-Filterresults: notjunk:1;V03:K0:s/Ou9L5RgVE=:+d/efHOTwa5FjR+DouPvJw +Rzm+wGwFhVPQcqUM0S6zXaTBQwUrf3zM+RPGf6IE9YL3sMR4OGQWHN+dWXSX0NDSaPirIRnt 9yLGAVH4Clmm02qRD/yUmRjCT1yUvBc3a7wliyV+XaHxoz47Dmndva+nDl4P7ryfrSYv9rW9y ZR7JWMtHN1AJ6Qbkt+0Ahrad4mC+RYKIAOW4QF2lHeHkp+RglEyfUQOTmPD6EQhnrDu2fKCFV 7oFMg7GTrh/1YvXqOMY9YHv94eWPm+U3Y5aZeo64xjckQnz0fNrvFQPATeDa8lDthWLIzBYkm dbHzVA7QUO7J7uz8PJwearWbsCbHtCnW3/mtO4BVGduP8eSPxBUj+vj3u0MLbdC/m9lCPOQ4a 9EOADdyXxsXPvaCqshHQucv62LMZrCtwF9OSee0xmqoh0hjBUv8iB4PTmF/F/pXHbfeqK6qhC 2znLT1u5AZlIe9HGtFgvegwo1YYLsblpebQw926A46hId7VKwRh5YJ+EndHHsusG3B/X4HH5j PFUGshPeV9+LploZRMfTfaJ5VJr3NL/hVzBzG6E/E4HCjQi/HAwwGQKsAvlXPm6wI+tBgzrQY HcMZlAFgSViBqNgPBHStjumP6oDXNck8uio7T5azXNwBTqhjsn/C4TW9CiDRo5U4m3xluTXD8 KCCso1T8vjduGKlsvhOIe3n7vrT62VEegjdxjpGB0ppGNGIc5j8vjI8C9mPk0in7ywxeo+tHA DHjlp5O/l553EIvYioEyKmOuRiQCX10+5CjCjrK+7VzpDAKzbAmtG7J1ZTC8f05GDw0Sdr7zp 9iyMm2i5PlcjCf9p7yZ+9r6y/Lwtrx7g02QRM2WsfIFjTNzjBnf3R8VfIWr7P+BYsSYsn4Gyn 9laWe6Ar9v6HDR3JUA9uIFT/0SU3vF3Z3lILnt1GFeCcw/OeXBWw4KNo62/yPU25XDBseO6tR 0dgYMBZySyuXObto2Kg4Hc4K2uqBpBOHCFt8tfjBWdC01NKfvanUk84eyt1DTulDgP65pUkA7 H6/vyNBGlsUJ0G2PNA/HW4O/yU9Qz/0X3aG8TgwwHB43WwIbkMZWlsTZAh4UBCzbydqC6+qrz YY8Mf70oZmu6PQVFrBys6CStLUDFKzRdYEJtTfmv9hoLF0yNNci+8ScHwUCIdOIlrzu3sT/tA lNe/XCZKnI0ZUSsQPfv9uJ8S3nbCGtpDoXi6VcTCsqm/FlL4x4AhMG1cOrINZhSEz4RFvblC0 usnjl2BFitds0lhi9L4F2GPtUGlicMHqhAnK2bA== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000001, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: > One problem with the kernel QC process is that I think everyone marks > the bug as "old/dealt with" Will this view trigger any more clarifications? > so it was only because I was added a new > check for resource leaks that it was found when it was re-introduced. I would like to point once more out that the commit 786ae133e07f2a6b352a0efad16b555ee45a2898 ("lib: fix test_hmm.c reference after free" from 2020-06-26) indicated questionable implementation details according to a coccicheck run. The available scripts for the semantic patch language can also remind you again for desirable software improvements. Examples: * https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/scripts/coccinelle/free/kfree.cocci?id=7c7ec3226f5f33f9c050d85ec20f18419c622ad6#n2 * https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/scripts/coccinelle/null/deref_null.cocci?id=7c7ec3226f5f33f9c050d85ec20f18419c622ad6#n3 Will any more adjustments be achieved with the help of advanced source code analysis tools? Regards, Markus