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 EC5D4C433EF for ; Sun, 24 Apr 2022 09:54:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236291AbiDXJ5C (ORCPT ); Sun, 24 Apr 2022 05:57:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39926 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237588AbiDXJ5C (ORCPT ); Sun, 24 Apr 2022 05:57:02 -0400 Received: from mail-wr1-x432.google.com (mail-wr1-x432.google.com [IPv6:2a00:1450:4864:20::432]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4481F644F8 for ; Sun, 24 Apr 2022 02:54:02 -0700 (PDT) Received: by mail-wr1-x432.google.com with SMTP id bv16so16874949wrb.9 for ; Sun, 24 Apr 2022 02:54:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:date:mime-version:user-agent:content-language:to:cc:from :subject:content-transfer-encoding; bh=PcnLo2ZjkPEzVs6ib0TY9iY3U327dNI+ekq4lJHhKmE=; b=ITRhOWxT0EzndKoub5QjUtx+4bMU/HqghN7hr9Sfeb3yZTJN4ZUrnCHOSA40vwW+Da U6FSQx+zmmTuRKPOnyN4yo5hzaNZSaGyfL8s69ZToi3Z7bZc3bUCWA8zVXQ7tnMF2Fiu m1SBLUZmIlzt8rI1o97s7q4uvb/YPYc7htQAz+QK19WKiCaL3BaY+xlcGnkX+MtTx0o2 la0Z8T6DIQTHcSpTNfx54o4/auKms4BET4inRL2RW4SVt36PIdsyjbu3dKZDkMLJAE5x 04QfUlT3V1bPxkp++b2pXIaCV1876UCwUyRnlC7PkdlwuGD5HHkIIKvlUpaAUCStsTrJ B0Lg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent :content-language:to:cc:from:subject:content-transfer-encoding; bh=PcnLo2ZjkPEzVs6ib0TY9iY3U327dNI+ekq4lJHhKmE=; b=Ur6xHenbj+v+W98FCI1TDyPKGn3mPKyyeSKPJDnsnJiIpbxyjirM327/HFOFWUEd9n Vq+jbYV7lo9P3JhlhSfX1okokbv88v/kAgKq2OzrLKxHPcWfDzBy9nWO33dK/3mH4Ig1 RSNX4su0jUgDeXDSpIjUc+vxCh8N5yUW/Ab/7pVsqmCCWCjA7FuU9WSczjmnVeT73Yan ArYwf0Rj1yq27DBQrjtroa/xo3NBzoOIkeHui+orTKVlqop9UiLl8nUwuo5w62/CDr5C HBeWqghZnvZV1B68SyUA0Rp5AVwSXsD92YmI0BsvRhmiNygEJC1Fr6y9R3/3ekorg195 3JkA== X-Gm-Message-State: AOAM531yqwqqVQfUeq0xqd6GSZlvjBO/QuVBGmnRBBTgHr66RxxLjdlv 6pgOPKSWJkLw0ZL1AGrJaOE= X-Google-Smtp-Source: ABdhPJz3WtBia9lsYiNtP36ly6C5/Spq+H8YUwiJhjB8D2sUUWuQU9zyuKAz/2H82/3raStSnz0L6A== X-Received: by 2002:a5d:6d8b:0:b0:20a:97c4:bdc6 with SMTP id l11-20020a5d6d8b000000b0020a97c4bdc6mr10055827wrs.156.1650794040804; Sun, 24 Apr 2022 02:54:00 -0700 (PDT) Received: from [0.0.0.0] ([95.179.233.4]) by smtp.gmail.com with ESMTPSA id r6-20020a1c4406000000b0039229d3c4eesm5993941wma.12.2022.04.24.02.53.58 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 24 Apr 2022 02:54:00 -0700 (PDT) Message-ID: <0663e8e2-8c09-eee4-159a-f82c67eba80e@gmail.com> Date: Sun, 24 Apr 2022 17:53:55 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:100.0) Gecko/20100101 Thunderbird/100.0 Content-Language: en-US To: Steve French Cc: kinglongmee@gmail.com, linux-cifs@vger.kernel.org From: Kinglong Mee Subject: cifsFileInfo leak when doing cifs_atomic_open on a symlink file Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org Hi steve, Recently I've started running LTP tests with mfsymlinks mount option. The LTP test "fs_racer" triggers the cifsFileInfo leak when doing cifs_atomic_open on a symlink file. After testing and umounting cifs mount, there are some files exist in /proc/fs/cifs/open_files as, #cat /proc/fs/cifs/open_files # Version:1 # Format: # 0x2 0x94c08 0x8401 1 1554873 0 11 0x2 0x94b5f 0x8401 1 1554808 0 7 0x2 0x947cf 0x8401 1 1554365 0 0 0x2 0x9470a 0x8401 1 1554339 0 0 and the tcp socket also left, # netstat -an |grep 445 tcp 0 0 192.168.123.123:38050 192.168.123.124:445 ESTABLISHED and the cifsd left too. # ps -ajx |grep cifsd 2 34030 0 0 ? -1 S 0 2:20 [cifsd] I found the fs_racer cause cifs doing cifs_atomic_open on symlink file, but the symlink file does not contain a valid i_fop setting, it means, the cifsFileInfo allocated for the symlink file never be un-referenced. I'd wanna know, is cifs_atomic_open on symlink file allowed? If allowed, a cifs_close for symlink file is needed. Otherwise, cifs_atomic_open needs return error for symlink file. Any comments are welcome. Thanks, Kinglong Mee