From patchwork Tue May 23 07:45:32 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 13251745 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 25DDEC7EE23 for ; Tue, 23 May 2023 07:48:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235427AbjEWHrx (ORCPT ); Tue, 23 May 2023 03:47:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42372 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235742AbjEWHrU (ORCPT ); Tue, 23 May 2023 03:47:20 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:3::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CDAE21B1; Tue, 23 May 2023 00:46:47 -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=4p5sa23zp651hB7qk2JiIaA7eX4JAqtNGdSL+Z6QwaA=; b=ggMWThfMQmAceRvr6onfS2llfO KbXpVileDx18p1lJK8gf2+ZUiUuEeE3bHNlnrb3fOeI12UNsUz9mNwjIolYCazTeMKJ92APqpAcva v2TqMxviArdInuPll1U0twBRNvM9Qgp1QG3iz7IGOYCJz/3nijzzoaPkBoLzgyPQH5E5K84M8RWl1 ++tigqx/Wc6cbswnzRWlEgWh5eB0GKZDO26mvWBzm8SVL5Vr2ZCU7x6bfWY2aP4UwlDLeofCr1fbU ItD62UDj6lJWYgAMcQD+TxpsogHgsMxYktATtigprtEWhH6tkfd2f64ZnZoFLPiEw3gi1incjYIM9 HX63dFOg==; 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 1q1Mj7-009HHx-1N; Tue, 23 May 2023 07:46:37 +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 21/24] PM: hibernate: don't use early_lookup_bdev in resume_store Date: Tue, 23 May 2023 09:45:32 +0200 Message-Id: <20230523074535.249802-22-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 resume_store is a sysfs attribute written during normal kernel runtime, and it should not use the early_lookup_bdev API that bypasses all normal path based permission checking, and might cause problems with certain container environments renaming devices. Switch to lookup_bdev, which does a normal path lookup instead, and fall back to trying to parse a numeric dev_t just like early_lookup_bdev did. 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 Fixes: 421a5fa1a6cf ("PM / hibernate: use name_to_dev_t to parse resume") Acked-by: Rafael J. Wysocki --- kernel/power/hibernate.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index c52dedb9f7c8e8..7ae95ec72f9902 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -1178,7 +1178,23 @@ static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr, if (!name) return -ENOMEM; - error = early_lookup_bdev(name, &dev); + error = lookup_bdev(name, &dev); + if (error) { + unsigned maj, min, offset; + char *p, dummy; + + if (sscanf(name, "%u:%u%c", &maj, &min, &dummy) == 2 || + sscanf(name, "%u:%u:%u:%c", &maj, &min, &offset, + &dummy) == 3) { + dev = MKDEV(maj, min); + if (maj != MAJOR(dev) || min != MINOR(dev)) + error = -EINVAL; + } else { + dev = new_decode_dev(simple_strtoul(name, &p, 16)); + if (*p) + error = -EINVAL; + } + } kfree(name); if (error) return error;