jffs2: make the overwritten xattr invisible after remount

euler inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I8TYET


CVE: NA

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For xattr modification, we do not write a new jffs2_raw_xref with
delete marker into flash, so if a xattr is modified then removed,
and the old xref & xdatum are not erased by GC, after reboot or
remount, the new xattr xref will be dead but the old xattr xref
will be alive, and we will get the overwritten xattr instead of
non-existent error when reading the removed xattr.

Fix it by writing the deletion mark for xattr overwrite.

Fixes: 8a13695c ("[JFFS2][XATTR] rid unnecessary writing of delete marker.")
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: ZhaoLong Wang <wangzhaolong1@huawei.com>