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: 1784914 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lists.infradead.org (client-ip=2607:7c80:54:3::133; helo=bombadil.infradead.org; envelope-from=linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org; receiver=) Authentication-Results: legolas.ozlabs.org; dkim=pass (2048-bit key; secure) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=gUVtRpKO; dkim-atps=neutral Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:3::133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-384) server-digest SHA384) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4QQRHB5DJDz20Pr for ; Tue, 23 May 2023 17:47:18 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=dhyv+voajTLBMsZiX1cA7xuAq6Ys1+RmcJ3Cemv8OFc=; b=gUVtRpKOeLKfRi sW/9iMkBtgO5Fz6p5m0euAuKbti6c0tLclIEeG13ME0p9LV2hIxXjmWnl78Vxp0l9fyvxis/q7GfU eJ1591tZ8ZIqjHQmaKAZrVkroLt7qWfxjb7kSTJuUwC/wnaMEDjlWiV3WCgKkCZwVOchzRv7odN2G 2GUugRc7/pSgpFdh4W/IQQbtReqJ30nZVUmCKFLTe+8NyC5ZJxLXfHYr8juWNwb/rYAPkQtLeOLpV xp64oEL+3YTdEShrRAPFrifb4cIixjHrZJgcHpJDmRWs/7TWF74Bp2jxl0SGjYLTL/2vjsGEWwEtR kMggBRt8fPymKA5S8Hsw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1q1MjK-009HYL-06; Tue, 23 May 2023 07:46:50 +0000 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-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-mtd" Errors-To: linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.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 Reviewed-by: Miquel Raynal --- 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.