From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp-33-i6.italiaonline.it ([213.209.14.33]:49412 "EHLO libero.it" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727804AbeITAUY (ORCPT ); Wed, 19 Sep 2018 20:20:24 -0400 From: Goffredo Baroncelli To: grub-devel@gnu.org Cc: Daniel Kiper , linux-btrfs@vger.kernel.org, Goffredo Baroncelli Subject: [PATCH 2/9] btrfs: Add helper to check the btrfs header. Date: Wed, 19 Sep 2018 20:40:33 +0200 Message-Id: <20180919184040.22540-3-kreijack@libero.it> In-Reply-To: <20180919184040.22540-1-kreijack@libero.it> References: <20180919184040.22540-1-kreijack@libero.it> MIME-Version: 1.0 Sender: linux-btrfs-owner@vger.kernel.org List-ID: From: Goffredo Baroncelli This helper is used in a few places to help the debugging. As conservative approach the error is only logged. This does not impact the error handling. Signed-off-by: Goffredo Baroncelli Reviewed-by: Daniel Kiper --- grub-core/fs/btrfs.c | 24 +++++++++++++++++++++++- 1 file changed, 23 insertions(+), 1 deletion(-) diff --git a/grub-core/fs/btrfs.c b/grub-core/fs/btrfs.c index 56c42746d..4f404f4b2 100644 --- a/grub-core/fs/btrfs.c +++ b/grub-core/fs/btrfs.c @@ -77,7 +77,8 @@ struct btrfs_header { grub_btrfs_checksum_t checksum; grub_btrfs_uuid_t uuid; - grub_uint8_t dummy[0x30]; + grub_uint64_t bytenr; + grub_uint8_t dummy[0x28]; grub_uint32_t nitems; grub_uint8_t level; } GRUB_PACKED; @@ -286,6 +287,25 @@ free_iterator (struct grub_btrfs_leaf_descriptor *desc) grub_free (desc->data); } +static grub_err_t +check_btrfs_header (struct grub_btrfs_data *data, struct btrfs_header *header, + grub_disk_addr_t addr) +{ + if (grub_le_to_cpu64 (header->bytenr) != addr) + { + grub_dprintf ("btrfs", "btrfs_header.bytenr is not equal node addr\n"); + return grub_error (GRUB_ERR_BAD_FS, + "header bytenr is not equal node addr"); + } + if (grub_memcmp (data->sblock.uuid, header->uuid, sizeof(grub_btrfs_uuid_t))) + { + grub_dprintf ("btrfs", "btrfs_header.uuid doesn't match sblock uuid\n"); + return grub_error (GRUB_ERR_BAD_FS, + "header uuid doesn't match sblock uuid"); + } + return GRUB_ERR_NONE; +} + static grub_err_t save_ref (struct grub_btrfs_leaf_descriptor *desc, grub_disk_addr_t addr, unsigned i, unsigned m, int l) @@ -341,6 +361,7 @@ next (struct grub_btrfs_data *data, err = grub_btrfs_read_logical (data, grub_le_to_cpu64 (node.addr), &head, sizeof (head), 0); + check_btrfs_header (data, &head, grub_le_to_cpu64 (node.addr)); if (err) return -err; @@ -402,6 +423,7 @@ lower_bound (struct grub_btrfs_data *data, /* FIXME: preread few nodes into buffer. */ err = grub_btrfs_read_logical (data, addr, &head, sizeof (head), recursion_depth + 1); + check_btrfs_header (data, &head, addr); if (err) return err; addr += sizeof (head); -- 2.19.0