Make udf_truncate_extents() properly propagate errors to its callers and
let udf_setsize() handle the error properly as well. This lets userspace
know in case there's some error when truncating blocks.

Signed-off-by: Jan Kara <jack@suse.cz>

When truncate(2) hits IO error when reading indirect extent block the
code just bugs with:

kernel BUG at linux-4.15.0/fs/udf/truncate.c:249!
...

Fix the problem by bailing out cleanly in case of IO error.

CC: stable@vger.kernel.org
Reported-by: jean-luc malet <jeanluc.malet@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

The check if (bh) in udf_sync_fs() is pointless as we cannot have
sbi->s_lvid_dirty and !sbi->s_lvid_bh (as already asserted by
udf_updated_lvid()). So just drop the pointless check.

Reviewed-by: Steven J. Magnani <steve@digidescorp.com>
Reported-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Jan Kara <jack@suse.cz>

Refuse to mount a volume read-write without a coherent Logical Volume
Integrity Descriptor, because we can't generate truly unique IDs without
one.

This fixes a bug where all inodes created on a UDF filesystem following
mount without a coherent LVID are assigned unique ID 0 which can then
confuse other UDF implementations.

Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Signed-off-by: Jan Kara <jack@suse.cz>

Make sure the CRC and tag checksum of the Logical Volume Integrity
Descriptor are valid before the structure is written out to disk.
Otherwise, unless the filesystem is unmounted gracefully, the on-disk
LVID will be invalid - which is unnecessary filesystem damage.

Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Signed-off-by: Jan Kara <jack@suse.cz>

Centralize timestamping and CRC/checksum updating of the in-core
Logical Volume Integrity Descriptor, in preparation for adding
a third site where this functionality is needed.

Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Signed-off-by: Jan Kara <jack@suse.cz>

Pull ext2, udf, and quota update from Jan Kara:
 "Some ext2 cleanups, a fix for UDF crash on corrupted media, and one
  quota locking fix"

* tag 'fs_for_4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  quota: Lock s_umount in exclusive mode for Q_XQUOTA{ON,OFF} quotactls.
  udf: Fix BUG on corrupted inode
  ext2: change reusable parameter to true when calling mb_cache_entry_create()
  ext2: remove redundant condition check
  ext2: avoid unnecessary operation in ext2_error()

When inode is corrupted so that extent type is invalid, some functions
(such as udf_truncate_extents()) will just BUG. Check that extent type
is valid when loading the inode to memory.

Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

Commit c26f6c615788 ("udf: Fix conversion of 'dstring' fields to UTF8")
started to be more strict when checking whether converted strings are
properly formatted. Sudip reports that there are DVDs where the volume
identification string is actually too long - UDF reports:

[  632.309320] UDF-fs: incorrect dstring lengths (32/32)

during mount and fails the mount. This is mostly harmless failure as we
don't need volume identification (and even less volume set
identification) for anything. So just truncate the volume identification
string if it is too long and replace it with 'Invalid' if we just cannot
convert it for other reasons. This keeps slightly incorrect media still
mountable.

CC: stable@vger.kernel.org
Fixes: c26f6c615788 ("udf: Fix conversion of 'dstring' fields to UTF8")
Reported-and-tested-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

Drop pack pragma. The header file defines only in-memory structures.

Signed-off-by: Jan Kara <jack@suse.cz>