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 X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CB073C433B4 for ; Wed, 7 Apr 2021 21:56:44 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6A652611C1 for ; Wed, 7 Apr 2021 21:56:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6A652611C1 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=makrotopia.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:Message-ID:Subject:Cc:To:From:Date: Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender :Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=LIdbdkMfgwLn1XCDjn7yJZ+2QfLFH6uT09iRbGkFT5k=; b=TE9STZ1tKjjIK23Ah9f1yYd96I Hy7IUTsdDRVuQXnDxCv95G+V8q5U5vnFkInb6r4DqjxvM/l/zpcSXr+Dl/fAdWRUC9JDcs3RqQUYa KOTYX+BR7qfUthO+YfC7a27C1/2PuD+2GvTFHrnYuiIfaee5zFYrWqF6iBTQX/3M2bl83Gr42LNQ4 +IFx3BXpLRkUuBklJ35tP9tO282CinSyPIRRKkw9shm1uWMEGKVgnf9THptgyzYc4b00NjYTpBjfA khsa6muEVBE7oR7Ic/pbRaWfvtarUkKKoDONt+E8T0qfydlFhQcaE2cligIrnJrWJxF+NAvwcs9mn EwOmlKDg==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lUG9W-00675F-JL; Wed, 07 Apr 2021 21:55:58 +0000 Received: from fudo.makrotopia.org ([2a07:2ec0:3002::71]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lUG9R-00673T-BW for linux-mtd@lists.infradead.org; Wed, 07 Apr 2021 21:55:56 +0000 Received: from local by fudo.makrotopia.org with esmtpsa (TLS1.3:TLS_AES_256_GCM_SHA384:256) (Exim 4.93.0.4) (envelope-from ) id 1lUG9M-0004ui-MP; Wed, 07 Apr 2021 23:55:48 +0200 Date: Wed, 7 Apr 2021 22:55:32 +0100 From: Daniel Golle To: linux-mtd@lists.infradead.org Cc: Vignesh Raghavendra , Richard Weinberger , Miquel Raynal , David Woodhouse Subject: [PATCH] mtd: super: don't reply on mtdblock device minor Message-ID: MIME-Version: 1.0 Content-Disposition: inline X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210407_225553_469855_397159B4 X-CRM114-Status: GOOD ( 13.83 ) 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-mtd" Errors-To: linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org For mtdblock devices with partitions (ie. part_bits != 0) the assumption that the minor number of the mtdblock device matches the mtdnum doesn't hold true. Properly resolve mtd device from blktrans layer instead. Signed-off-by: Daniel Golle --- drivers/mtd/mtdsuper.c | 33 ++++++++++++++++++++++++++------- 1 file changed, 26 insertions(+), 7 deletions(-) diff --git a/drivers/mtd/mtdsuper.c b/drivers/mtd/mtdsuper.c index c3e2098372f2e..dc52f9929c8fb 100644 --- a/drivers/mtd/mtdsuper.c +++ b/drivers/mtd/mtdsuper.c @@ -9,6 +9,7 @@ */ #include +#include #include #include #include @@ -121,7 +122,8 @@ int get_tree_mtd(struct fs_context *fc, { #ifdef CONFIG_BLOCK struct block_device *bdev; - int ret, major; + struct mtd_blktrans_dev *blktrans_dev; + int ret, major, part_bits; #endif int mtdnr; @@ -169,21 +171,38 @@ int get_tree_mtd(struct fs_context *fc, /* try the old way - the hack where we allowed users to mount * /dev/mtdblock$(n) but didn't actually _use_ the blockdev */ - bdev = lookup_bdev(fc->source); + bdev = blkdev_get_by_path(fc->source, FMODE_READ, NULL); if (IS_ERR(bdev)) { ret = PTR_ERR(bdev); errorf(fc, "MTD: Couldn't look up '%s': %d", fc->source, ret); return ret; } - pr_debug("MTDSB: lookup_bdev() returned 0\n"); + pr_debug("MTDSB: blkdev_get_by_path() returned 0\n"); major = MAJOR(bdev->bd_dev); - mtdnr = MINOR(bdev->bd_dev); - bdput(bdev); - if (major == MTD_BLOCK_MAJOR) - return mtd_get_sb_by_nr(fc, mtdnr, fill_super); + if (major == MTD_BLOCK_MAJOR) { + if (!bdev->bd_disk) { + blkdev_put(bdev, FMODE_READ); + BUG(); + return -EINVAL; + } + + blktrans_dev = (struct mtd_blktrans_dev *)(bdev->bd_disk->private_data); + if (!blktrans_dev || !blktrans_dev->tr) { + blkdev_put(bdev, FMODE_READ); + BUG(); + return -EINVAL; + } + mtdnr = blktrans_dev->devnum; + part_bits = blktrans_dev->tr->part_bits; + blkdev_put(bdev, FMODE_READ); + if (MINOR(bdev->bd_dev) != (mtdnr << part_bits)) + return -EINVAL; + return mtd_get_sb_by_nr(fc, mtdnr, fill_super); + } + blkdev_put(bdev, FMODE_READ); #endif /* CONFIG_BLOCK */ if (!(fc->sb_flags & SB_SILENT)) -- 2.31.0 ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/