nilfs2: add missing check for inode numbers on directory entries

stable inclusion
from stable-v5.10.223
commit 2f2fa9cf7c3537958a82fbe8c8595a5eb0861ad7
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAGPRT
CVE: CVE-2024-42104

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=linux-5.10.y&id=2f2fa9cf7c3537958a82fbe8c8595a5eb0861ad7

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

commit bb76c6c274683c8570ad788f79d4b875bde0e458 upstream.

Syzbot reported that mounting and unmounting a specific pattern of
corrupted nilfs2 filesystem images causes a use-after-free of metadata
file inodes, which triggers a kernel bug in lru_add_fn().

As Jan Kara pointed out, this is because the link count of a metadata file
gets corrupted to 0, and nilfs_evict_inode(), which is called from iput(),
tries to delete that inode (ifile inode in this case).

The inconsistency occurs because directories containing the inode numbers
of these metadata files that should not be visible in the namespace are
read without checking.

Fix this issue by treating the inode numbers of these internal files as
errors in the sanity check helper when reading directory folios/pages.

Also thanks to Hillf Danton and Matthew Wilcox for their initial mm-layer
analysis.

Link: https://lkml.kernel.org/r/20240623051135.4180-3-konishi.ryusuke@gmail.com


Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by:  <syzbot+d79afb004be235636ee8@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=d79afb004be235636ee8


Reported-by: Jan Kara <jack@suse.cz>
Closes: https://lkml.kernel.org/r/20240617075758.wewhukbrjod5fp5o@quack3


Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Xia Fukun <xiafukun@huawei.com>