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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 3352DC352A3 for ; Mon, 10 Feb 2020 12:45:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 02AEC2051A for ; Mon, 10 Feb 2020 12:45:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581338700; bh=8HSn47iVmVuHK5R6HJ9DPCtyktsjn3EOBpK6AgA2IB0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=aYHFxkeFNuo2m3vVCsNq90D/PRBywRflsZdY+CGjKmt716Jgo6LYfuPaudhGiwyX1 MEqPc1GLNe4Blhz7RYDxdAaqSZHt7NtnCoIxXo/lB67m3j4V/lqvaB0VVv3kCYTf/4 /ePKpJNit+Vyi2mxVEq+cQ64foxX2nQ6VxUFIy+w= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730746AbgBJMo7 (ORCPT ); Mon, 10 Feb 2020 07:44:59 -0500 Received: from mail.kernel.org ([198.145.29.99]:41670 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729803AbgBJMkt (ORCPT ); Mon, 10 Feb 2020 07:40:49 -0500 Received: from localhost (unknown [209.37.97.194]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id AEB7320661; Mon, 10 Feb 2020 12:40:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581338448; bh=8HSn47iVmVuHK5R6HJ9DPCtyktsjn3EOBpK6AgA2IB0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OF/9f8hHWMkCzGo1FfqkPnbjFvqUyzSCyx5GDoqYaJfyK80vNHGJckrgUWnYsR6cI AqM2DqFuLXhAR5hrVOt0b64+g7n0h3DFDCfMWqFnbL/8evvF6El/e3G8jtJlDQ9Aqj zQfHyB/POSY3RxTWtmziXtSuvdN8ewwkBZvLf/Ns= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, stable@kernel.org, Vasily Averin , Jan Kara , Theodore Tso Subject: [PATCH 5.5 192/367] jbd2_seq_info_next should increase position index Date: Mon, 10 Feb 2020 04:31:45 -0800 Message-Id: <20200210122442.319188014@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200210122423.695146547@linuxfoundation.org> References: <20200210122423.695146547@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Vasily Averin commit 1a8e9cf40c9a6a2e40b1e924b13ed303aeea4418 upstream. if seq_file .next fuction does not change position index, read after some lseek can generate unexpected output. Script below generates endless output $ q=;while read -r r;do echo "$((++q)) $r";done Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/d13805e5-695e-8ac3-b678-26ca2313629f@virtuozzo.com Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman --- fs/jbd2/journal.c | 1 + 1 file changed, 1 insertion(+) --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -982,6 +982,7 @@ static void *jbd2_seq_info_start(struct static void *jbd2_seq_info_next(struct seq_file *seq, void *v, loff_t *pos) { + (*pos)++; return NULL; }