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=-9.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,T_DKIMWL_WL_HIGH,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 BE81BC468BD for ; Sun, 9 Jun 2019 17:02:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8EFDF207E0 for ; Sun, 9 Jun 2019 17:02:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560099776; bh=zXy8nO5A7IVBg+N3rB34CovA3fHyL9pOXlgnFXZtya0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=gIQsyNzp4Qd9+h88xe2W9QQC4ugAeECUwhZLne1TwiE9FPfMIcuRokRnshTZxn7ax lTB1bq/CAsNCJYEtRYFhcfcUtrueQGLGN+j9F8yRdJVo8D1FkJUIy2wnGmQePqKou3 jE0G01ZO4u263R5bUNEJcOA7lEiHT51d9WK8VXvE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388332AbfFIRCz (ORCPT ); Sun, 9 Jun 2019 13:02:55 -0400 Received: from mail.kernel.org ([198.145.29.99]:40996 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388302AbfFIRCw (ORCPT ); Sun, 9 Jun 2019 13:02:52 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 81FCE206DF; Sun, 9 Jun 2019 17:02:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560099772; bh=zXy8nO5A7IVBg+N3rB34CovA3fHyL9pOXlgnFXZtya0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gdRJm20UBxeN3WLL8WcCdQPjjEu1Ad3wZHO52PKvAu5OQCzAYmPGQbV6BfHGC4uWK AwG4vWzBHtVK+wNf4psC8CuHJaHs7XwJywTjlY2sn4zjVPTkHwFt+/8NtfrGNIt318 r+gvfoLvdX7uZZyYWiCU+Yi/7/O5xRV91OLx3brA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Chengguang Xu , Sasha Levin Subject: [PATCH 4.4 160/241] chardev: add additional check for minor range overlap Date: Sun, 9 Jun 2019 18:41:42 +0200 Message-Id: <20190609164152.386477349@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190609164147.729157653@linuxfoundation.org> References: <20190609164147.729157653@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 [ Upstream commit de36e16d1557a0b6eb328bc3516359a12ba5c25c ] Current overlap checking cannot correctly handle a case which is baseminor < existing baseminor && baseminor + minorct > existing baseminor + minorct. Signed-off-by: Chengguang Xu Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- fs/char_dev.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/char_dev.c b/fs/char_dev.c index 24b142569ca9b..d0655ca894816 100644 --- a/fs/char_dev.c +++ b/fs/char_dev.c @@ -130,6 +130,12 @@ __register_chrdev_region(unsigned int major, unsigned int baseminor, ret = -EBUSY; goto out; } + + if (new_min < old_min && new_max > old_max) { + ret = -EBUSY; + goto out; + } + } cd->next = *cp; -- 2.20.1