From patchwork Tue May 23 07:45:34 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 685251 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 F1A6DC7EE26 for ; Tue, 23 May 2023 07:48:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235774AbjEWHsW (ORCPT ); Tue, 23 May 2023 03:48:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43328 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235792AbjEWHrn (ORCPT ); Tue, 23 May 2023 03:47:43 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:3::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A0D0D133; Tue, 23 May 2023 00:46:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=rB1XU3Q8mH+jzryPymiOq8Z/Y0ZEGIxvnUDI5lAUFnE=; b=IR3nBxbwuu4MvPChQwEdKu7V2t xvTbSx8RpoJmbaknVJE3FRJUB6ZAhXcsqBq6+bDaCYEso5zOtbKW4kdNUovGSy1cTwV7uWaC76p3N 8K5EiUbtIqL48X/CNwd2ZD9JxfiMbTKmQlkwf/vshQJzaNFKR/QG41jChIm2cCdWwlHGWrUkQqRm0 z649ZBBMXxltpSAY9YfGkv0KEDD1np48IkIbTBbgUIM9snFv/mWKs4QgQqLg3BOvgiT2qN3oycCI9 C9mn8cH/4bGVSXIcLByijq5fhix9QwhCzaWWsqA5BChrcJ5ojWsbTmGp/OTc23+aAP9hq/duaKrzg S4lHoyCg==; Received: from [2001:4bb8:188:23b2:6ade:85c9:530f:6eb0] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.96 #2 (Red Hat Linux)) id 1q1MjD-009HOR-0Y; Tue, 23 May 2023 07:46:43 +0000 From: Christoph Hellwig To: Jens Axboe Cc: Greg Kroah-Hartman , "Rafael J. Wysocki" , Mike Snitzer , Joern Engel , Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Pavel Machek , dm-devel@redhat.com, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-mtd@lists.infradead.org, linux-pm@vger.kernel.org Subject: [PATCH 23/24] mtd: block2mtd: don't call early_lookup_bdev after the system is running Date: Tue, 23 May 2023 09:45:34 +0200 Message-Id: <20230523074535.249802-24-hch@lst.de> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230523074535.249802-1-hch@lst.de> References: <20230523074535.249802-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org early_lookup_bdev is supposed to only be called from the early boot code, but mdtblock_early_get_bdev is called as a general fallback when lookup_bdev fails, which is problematic because early_lookup_bdev bypasses all normal path based permission checking, and might cause problems with certain container environments renaming devices. Switch to only call early_lookup_bdev when dm is built-in and the system state in not running yet. Note that this strictly speaking changes the kernel ABI as the PARTUUID= and PARTLABEL= style syntax is now not available during a running systems. They never were intended for that, but this breaks things we'll have to figure out a way to make them available again. But if avoidable in any way I'd rather avoid that. Signed-off-by: Christoph Hellwig --- drivers/mtd/devices/block2mtd.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/mtd/devices/block2mtd.c b/drivers/mtd/devices/block2mtd.c index 182eed68c75634..59e4c71cfc6f53 100644 --- a/drivers/mtd/devices/block2mtd.c +++ b/drivers/mtd/devices/block2mtd.c @@ -215,13 +215,23 @@ static void block2mtd_free_device(struct block2mtd_dev *dev) kfree(dev); } -static struct block_device *mdtblock_early_get_bdev(const char *devname, +/* + * This function is marked __ref because it calls the __init marked + * early_lookup_bdev when called from the early boot code. + */ +static struct block_device __ref *mdtblock_early_get_bdev(const char *devname, fmode_t mode, int timeout, struct block2mtd_dev *dev) { struct block_device *bdev = ERR_PTR(-ENODEV); #ifndef MODULE int i; + /* + * We can't use early_lookup_bdev from a running system. + */ + if (system_state >= SYSTEM_RUNNING) + return bdev; + /* * We might not have the root device mounted at this point. * Try to resolve the device name by other means.