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=-2.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT 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 87A2EC46464 for ; Mon, 13 Aug 2018 07:38:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3B49C21829 for ; Mon, 13 Aug 2018 07:38:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="igP27H6K" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3B49C21829 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728867AbeHMKTc (ORCPT ); Mon, 13 Aug 2018 06:19:32 -0400 Received: from mail-pf1-f194.google.com ([209.85.210.194]:41724 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728244AbeHMKTc (ORCPT ); Mon, 13 Aug 2018 06:19:32 -0400 Received: by mail-pf1-f194.google.com with SMTP id y10-v6so7301138pfn.8 for ; Mon, 13 Aug 2018 00:38:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=ZmVQu1xcdp8gosU+cNNImlNo9JoeUpkWVp6y4d0w3Bs=; b=igP27H6K6Z2Q0MN2SbqVdTLzgv8PKPJeBS+x/Z0Z+GDqtd5uVUEcRkDjwFpfVMsMpy Wm37a5i+sbYjVjHX3PUseH+IOH69Wnn19PbHsttvJtykvYDZW/CbVwl+HifzA8VaLKT/ yN6Fms3nyXKViyvpNG0LPs/dwv7wK3/XeOniiT+qIfpbDaAQQe1gmE8RquEwhNjfCTn4 RgNezAH6ihhyCfG7rTyLeRypnyNjsORGnB5y49ra/f1yaHme4kUIeaXknsUl4aKXX+h4 grCc8z3HjNLkY1/BmgZL2aI/GPHHvOKnEftmsFi7C+84lWY2wU9bHlone8XYNpMJNe5s JSZQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=ZmVQu1xcdp8gosU+cNNImlNo9JoeUpkWVp6y4d0w3Bs=; b=Xj3poYtN8fvar812SsOSNPYxpQkZfh7FGYix/ujAfqNjoN/M4VXoBY3DdM7o8cpOtr iNVubIf7+go+r9k+5noz0m7NIsFTUE8HAmGC1WfGcMfruy6aGP/QVaAr++7Kf5NOMQQL BFxWmJwVKPqIUJr+Qh1iN+5tdjTk6c0//Pfa9LmUmJN2yKRCRmRvsg4wiAEC+gki61hy Wx76m+QKdl/t04W68NrsFdlZ80ACM7Rj6cnGb4TLtdwIb/Tw5tgYbixSSC/wfWO21s5o xTET06bYq21zIL2gMF8q2qMWdacQxxXplKRovuMlRj4632SvjlePrJ9lftd1J4+knTBc nUAA== X-Gm-Message-State: AOUpUlGd8mFFfrJiPGcchjNUu5bqOomuGcimrDQKD59bnshIge8a64lh gwmlA3K12TdoGjcw1MAm3Qc= X-Google-Smtp-Source: AA+uWPyQm24aM50HobcAYEB7SvFiOS4joS4h7Sh2qkFqSMdIEvhi8bcUJPeYgK+NGrnC2iy2gPr/Dw== X-Received: by 2002:a63:5b51:: with SMTP id l17-v6mr15661529pgm.165.1534145909942; Mon, 13 Aug 2018 00:38:29 -0700 (PDT) Received: from localhost ([110.70.54.242]) by smtp.gmail.com with ESMTPSA id h190-v6sm23131038pge.85.2018.08.13.00.38.27 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Mon, 13 Aug 2018 00:38:28 -0700 (PDT) Date: Mon, 13 Aug 2018 16:38:25 +0900 From: Sergey Senozhatsky To: Minchan Kim Cc: Peter Kalauskas , LKML , Sergey Senozhatsky , Andrew Morton Subject: Re: [PATCH] zram: fix bug storing backing_dev Message-ID: <20180813073825.GA1062@jagdpanzerIV> References: <20180808223100.225086-1-peskal@google.com> <20180813061623.GC64836@rodete-desktop-imager.corp.google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180813061623.GC64836@rodete-desktop-imager.corp.google.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (08/13/18 15:16), Minchan Kim wrote: > > The call to strlcpy in backing_dev_store is incorrect. It should take > > the size of the destination buffer instead of the size of the source > > buffer. Additionally, ignore the newline character (\n) when reading > > the new file_name buffer. This makes it possible to set the backing_dev > > as follows: > > > > echo /dev/sdX > /sys/block/zram0/backing_dev > > > > Signed-off-by: Peter Kalauskas > Acked-by: Minchan Kim > > Cc: Andrew Morton > Cc: Sergey Senozhatsky > CC: LKML > Cc: [4.14+] Thanks for Cc-ing Minchan. Reviewed-by: Sergey Senozhatsky > > - strlcpy(file_name, buf, len); This is quite interesting. The reason it worked before was the fact that strlcpy() copies 'len - 1' bytes, which is strlen(buf) - 1 in our case, so it accidentally didn't copy the trailing new line symbol. Which also means that "echo -n /dev/sdX" most likely was broken. -ss