btrfs: use proper endianness accessors for super_copy
authorAnand Jain <anand.jain@oracle.com>
Thu, 22 Feb 2018 13:58:42 +0000 (21:58 +0800)
committerDavid Sterba <dsterba@suse.com>
Thu, 1 Mar 2018 15:17:27 +0000 (16:17 +0100)
commit3c181c12c431fe33b669410d663beb9cceefcd1b
treeb61293279ddd4b89037339fff51de0a63a9e635f
parent92e222df7b8f05c565009c7383321b593eca488b
btrfs: use proper endianness accessors for super_copy

The fs_info::super_copy is a byte copy of the on-disk structure and all
members must use the accessor macros/functions to obtain the right
value.  This was missing in update_super_roots and in sysfs readers.

Moving between opposite endianness hosts will report bogus numbers in
sysfs, and mount may fail as the root will not be restored correctly. If
the filesystem is always used on a same endian host, this will not be a
problem.

Fix this by using the btrfs_set_super...() functions to set
fs_info::super_copy values, and for the sysfs, use the cached
fs_info::nodesize/sectorsize values.

CC: stable@vger.kernel.org
Fixes: df93589a17378 ("btrfs: export more from FS_INFO to sysfs")
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
fs/btrfs/sysfs.c
fs/btrfs/transaction.c