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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 AE8BDC3F2D2 for ; Tue, 3 Mar 2020 02:57:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 797D52166E for ; Tue, 3 Mar 2020 02:57:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1583204250; bh=Xvrs5Tl05cV7m4ac4tT9EVzboSu3Qc+AUWzumDZp8DI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=YBJK4IVYTzwfcW6xeXPz72/ysXaC+oGB7JSafOrD7D8oAsdMJFNzoKiu+09TysaOm Qbmp/NQcFevaPcXwlsnVTI1oFH3I7MHvs82SOEfux9dUvfDrZ6AULOVmm9d/cG9YU+ ngGsbbIIZmOTxJGJOWTMDMV0s1GemDYov5Y3+WT4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728394AbgCCC50 (ORCPT ); Mon, 2 Mar 2020 21:57:26 -0500 Received: from mail.kernel.org ([198.145.29.99]:44034 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728388AbgCCCsV (ORCPT ); Mon, 2 Mar 2020 21:48:21 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5CA08246A1; Tue, 3 Mar 2020 02:48:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1583203701; bh=Xvrs5Tl05cV7m4ac4tT9EVzboSu3Qc+AUWzumDZp8DI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=U922rcbUW4cf566g89zPi3prQi7gyPRp10jWTUhAw/9kY2Uc2H7PnT+xDhs+JL89s /G+pPx5eAjVeLTcALuBZ1zmpThetYl36DpFhSFq0LWQ+WLyg/+JeSM2qfaPDFzlNc2 IHRO6FwDsBF8lM/sQZsy14h3SaVL36S/NsRgQ204= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Vasily Averin , Cornelia Huck , Christian Borntraeger , Vasily Gorbik , Sasha Levin , linux-s390@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 33/58] s390/cio: cio_ignore_proc_seq_next should increase position index Date: Mon, 2 Mar 2020 21:47:15 -0500 Message-Id: <20200303024740.9511-33-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200303024740.9511-1-sashal@kernel.org> References: <20200303024740.9511-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Vasily Averin [ Upstream commit 8b101a5e14f2161869636ff9cb4907b7749dc0c2 ] if seq_file .next fuction does not change position index, read after some lseek can generate unexpected output. Link: https://bugzilla.kernel.org/show_bug.cgi?id=206283 Link: https://lore.kernel.org/r/d44c53a7-9bc1-15c7-6d4a-0c10cb9dffce@virtuozzo.com Reviewed-by: Cornelia Huck Signed-off-by: Christian Borntraeger Signed-off-by: Vasily Averin Signed-off-by: Vasily Gorbik Signed-off-by: Sasha Levin --- drivers/s390/cio/blacklist.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/s390/cio/blacklist.c b/drivers/s390/cio/blacklist.c index 2a3f874a21d54..9cebff8e8d740 100644 --- a/drivers/s390/cio/blacklist.c +++ b/drivers/s390/cio/blacklist.c @@ -303,8 +303,10 @@ static void * cio_ignore_proc_seq_next(struct seq_file *s, void *it, loff_t *offset) { struct ccwdev_iter *iter; + loff_t p = *offset; - if (*offset >= (__MAX_SUBCHANNEL + 1) * (__MAX_SSID + 1)) + (*offset)++; + if (p >= (__MAX_SUBCHANNEL + 1) * (__MAX_SSID + 1)) return NULL; iter = it; if (iter->devno == __MAX_SUBCHANNEL) { @@ -314,7 +316,6 @@ cio_ignore_proc_seq_next(struct seq_file *s, void *it, loff_t *offset) return NULL; } else iter->devno++; - (*offset)++; return iter; } -- 2.20.1