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 B9BF3C433F5 for ; Mon, 4 Apr 2022 10:13:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240890AbiDDKP2 (ORCPT ); Mon, 4 Apr 2022 06:15:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56580 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244282AbiDDKP2 (ORCPT ); Mon, 4 Apr 2022 06:15:28 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 26C56D9F for ; Mon, 4 Apr 2022 03:13:32 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id B9F0B614E2 for ; Mon, 4 Apr 2022 10:13:31 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BEFA4C2BBE4; Mon, 4 Apr 2022 10:13:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1649067211; bh=ht9X7swWPVbhO0CX++MyDmSLGK1uFIJXcjq02xgdfKE=; h=Subject:To:Cc:From:Date:From; b=MsD4p3z/EkN8rbfJJiw7707Kw6ZyXVm1bfvDh66HaXLJc5cSXbdgg+JYlFpEItV4z vKpwhLoI+OJOOA3v7AOfM8uqnH9xkH/jXCxOY6AvqbCaLiIwHq0wULf0MHKcEd8/6N 9HChswdtKTBdXFAyy80xxzT/9JK+sHwQxlLIDDBU= Subject: FAILED: patch "[PATCH] nbd: fix possible overflow on 'first_minor' in nbd_dev_add()" failed to apply to 5.15-stable tree To: zhangwensheng5@huawei.com, axboe@kernel.dk, josef@toxicpanda.com Cc: From: Date: Mon, 04 Apr 2022 12:13:28 +0200 Message-ID: <1649067208247118@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 6d35d04a9e18990040e87d2bbf72689252669d54 Mon Sep 17 00:00:00 2001 From: Zhang Wensheng Date: Thu, 10 Mar 2022 17:32:24 +0800 Subject: [PATCH] nbd: fix possible overflow on 'first_minor' in nbd_dev_add() When 'index' is a big numbers, it may become negative which forced to 'int'. then 'index << part_shift' might overflow to a positive value that is not greater than '0xfffff', then sysfs might complains about duplicate creation. Because of this, move the 'index' judgment to the front will fix it and be better. Fixes: b0d9111a2d53 ("nbd: use an idr to keep track of nbd devices") Fixes: 940c264984fd ("nbd: fix possible overflow for 'first_minor' in nbd_dev_add()") Signed-off-by: Zhang Wensheng Reviewed-by: Josef Bacik Link: https://lore.kernel.org/r/20220310093224.4002895-1-zhangwensheng5@huawei.com Signed-off-by: Jens Axboe diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index 5a1f98494ddd..b3cdfc0ffb98 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -1800,17 +1800,6 @@ static struct nbd_device *nbd_dev_add(int index, unsigned int refs) refcount_set(&nbd->refs, 0); INIT_LIST_HEAD(&nbd->list); disk->major = NBD_MAJOR; - - /* Too big first_minor can cause duplicate creation of - * sysfs files/links, since index << part_shift might overflow, or - * MKDEV() expect that the max bits of first_minor is 20. - */ - disk->first_minor = index << part_shift; - if (disk->first_minor < index || disk->first_minor > MINORMASK) { - err = -EINVAL; - goto out_free_work; - } - disk->minors = 1 << part_shift; disk->fops = &nbd_fops; disk->private_data = nbd; @@ -1915,8 +1904,19 @@ static int nbd_genl_connect(struct sk_buff *skb, struct genl_info *info) if (!netlink_capable(skb, CAP_SYS_ADMIN)) return -EPERM; - if (info->attrs[NBD_ATTR_INDEX]) + if (info->attrs[NBD_ATTR_INDEX]) { index = nla_get_u32(info->attrs[NBD_ATTR_INDEX]); + + /* + * Too big first_minor can cause duplicate creation of + * sysfs files/links, since index << part_shift might overflow, or + * MKDEV() expect that the max bits of first_minor is 20. + */ + if (index < 0 || index > MINORMASK >> part_shift) { + printk(KERN_ERR "nbd: illegal input index %d\n", index); + return -EINVAL; + } + } if (!info->attrs[NBD_ATTR_SOCKETS]) { printk(KERN_ERR "nbd: must specify at least one socket\n"); return -EINVAL;