From 941b2ddf71987ef369389517a7e215dd505fe01e Mon Sep 17 00:00:00 2001 From: Keith Mannthey Date: Tue, 29 Nov 2011 17:44:12 -0800 Subject: btrfs: Sector Size check during Mount Gracefully fail when trying to mount a BTRFS file system that has a sectorsize smaller than PAGE_SIZE. On PPC it is possible to build a FS while using a 4k PAGE_SIZE kernel then boot into a 64K PAGE_SIZE kernel. Presently open_ctree fails in an endless loop and hangs the machine in this situation. My debugging has show this Sector size < Page size to be a non trivial situation and a graceful exit from the situation would be nice for the time being. Signed-off-by: Keith Mannthey --- fs/btrfs/disk-io.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'fs/btrfs/disk-io.c') diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 4c867112b4c8..58d0678dfcba 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -2258,6 +2258,12 @@ struct btrfs_root *open_ctree(struct super_block *sb, goto fail_sb_buffer; } + if (sectorsize < PAGE_SIZE) { + printk(KERN_WARNING "btrfs: Incompatible sector size " + "found on %s\n", sb->s_id); + goto fail_sb_buffer; + } + mutex_lock(&fs_info->chunk_mutex); ret = btrfs_read_sys_array(tree_root); mutex_unlock(&fs_info->chunk_mutex); -- cgit v1.2.3 From a6b0d5c8dbfd428717fc4db4c36757783f391c7b Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Mon, 20 Feb 2012 20:53:43 -0500 Subject: Btrfs: make sure we update latest_bdev When we are setting up the mount, we close all the devices that were not actually part of the metadata we found. But, we don't make sure that one of those devices wasn't fs_devices->latest_bdev, which means we can do a use after free on the one we closed. This updates latest_bdev as it goes. Signed-off-by: Chris Mason --- fs/btrfs/disk-io.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'fs/btrfs/disk-io.c') diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 58d0678dfcba..b801d29f3f10 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -2305,6 +2305,12 @@ struct btrfs_root *open_ctree(struct super_block *sb, btrfs_close_extra_devices(fs_devices); + if (!fs_devices->latest_bdev) { + printk(KERN_CRIT "btrfs: failed to read devices on %s\n", + sb->s_id); + goto fail_tree_roots; + } + retry_root_backup: blocksize = btrfs_level_size(tree_root, btrfs_super_root_level(disk_super)); -- cgit v1.2.3