From patchwork Tue May 23 07:45:31 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 685253 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 8F4B3C77B75 for ; Tue, 23 May 2023 07:47:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232661AbjEWHrs (ORCPT ); Tue, 23 May 2023 03:47:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42468 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235658AbjEWHqy (ORCPT ); Tue, 23 May 2023 03:46:54 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:3::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D768011A; Tue, 23 May 2023 00:46:43 -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=BOtvo2QkhpnKNrqVZX60VmJ53d8jKRahCxNIQR8Da1k=; b=VJ7bzvqRzAknKL8HckX4vSg28u XVN0Nn6Q5RMRGID0IU1iNT7xuFOy/iGqFqXvFP0jDsjFuR7hl9SEUNbqoLBA1CMA0ngC2JFqOx0L1 MZqtHp3RJ6L+HLgDygEC3Yarhx6JEHZgA7nBDqqpxKRczJUFvJBR3ksCqiW2llzT4aiFc7K5mLs+H hhZP2DpK6VXsj9vaXqI7jQe4UB4eu4xp6THLqLROh7dX0qihSfnWi3/5qRyc5YgcDkorsm6nDD1nq yngrtl+ugiHEjMfgkPcWXw9q2pWGObpvhvVbPb5rBELOgqpuC0GV4gH/j/lcfktgz8cDRA4Bqq8aW x64HC7+A==; 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 1q1Mj4-009HEh-16; Tue, 23 May 2023 07:46:34 +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 20/24] dm: only call early_lookup_bdev from early boot context Date: Tue, 23 May 2023 09:45:31 +0200 Message-Id: <20230523074535.249802-21-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 dm_get_device calls it 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. This means it is still available when tables are constructed by dm-init.c from the kernel command line, but not otherwise. 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/md/dm-table.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index e997f4322a9967..c230241a76b374 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -326,8 +326,11 @@ static int upgrade_mode(struct dm_dev_internal *dd, fmode_t new_mode, /* * Add a device to the list, or just increment the usage count if * it's already present. + * + * Note: the __ref annotation is because this function can call the __init + * marked early_lookup_bdev when called during early boot code from dm-init.c. */ -int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode, +int __ref dm_get_device(struct dm_target *ti, const char *path, fmode_t mode, struct dm_dev **result) { int r; @@ -346,8 +349,10 @@ int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode, return -EOVERFLOW; } else { r = lookup_bdev(path, &dev); - if (r) +#ifndef MODULE + if (r && system_state < SYSTEM_RUNNING) r = early_lookup_bdev(path, &dev); +#endif if (r) return -ENODEV; }