ocfs2: fix zero out valid data

stable inclusion
from stable-v5.10.56
commit 94301459306115e007966bd607638232423d15d9
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9909V
CVE: CVE-2021-47114

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=94301459306115e007966bd607638232423d15d9

--------------------------------

commit f267aeb6 upstream.

If append-dio feature is enabled, direct-io write and fallocate could
run in parallel to extend file size, fallocate used "orig_isize" to
record i_size before taking "ip_alloc_sem", when
ocfs2_zeroout_partial_cluster() zeroout EOF blocks, i_size maybe already
extended by ocfs2_dio_end_io_write(), that will cause valid data zeroed
out.

Link: https://lkml.kernel.org/r/20210722054923.24389-1-junxiao.bi@oracle.com


Fixes: 6bba4471 ("ocfs2: fix data corruption by fallocate")
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Yifan Qiao <qiaoyifan4@huawei.com>