Description of problem:
File with Filename size 256bytes is not accessible after fscrypt unlock.
File was accessible after creation, after lock in encrypted format, but after fscrypt unlock same file is not accessible.

Logs:

[root@ceph-sumar-fscrypt-az0v8f-node6 fuse_sv1]# date
Fri Apr 25 09:45:54 UTC 2025
[root@ceph-sumar-fscrypt-az0v8f-node6 fuse_sv1]# ls -l testdir1/
ls: cannot access 'testdir1/???': No such file or directory
total 1583333
-?????????? ? ?        ?                ?            ? '???'

[root@ceph-sumar-fscrypt-az0v8f-node6 fuse_sv1]# date
Fri Apr 25 09:51:48 UTC 2025
[root@ceph-sumar-fscrypt-az0v8f-node6 fuse_sv1]# ls -l testdir1/
ls: cannot access 'testdir1/???': No such file or directory
total 1583333
-?????????? ? ?        ?                ?            ? '???'

Version-Release number of selected component (if applicable):


How reproducible:


Steps to Reproduce:
1. Setup fscrypt on test directpry in ceph-fuse mount of subvolume
2.Create a file with filename size being 256bytes
3.Perform fscrypt lock and verify encryption of filename in step2
Observation : Filename in encrypted format could be listed and size was 249bytes
4. Perform fscrypt unlock and verify filename encryption removed and is accessible.

Actual results: Filename is not accessible, neither file stats like size, timestamp are printed.


Expected results: Filename should be accessible after fscrypt unlock.


Additional info: Detailed logs for steps followed is below. Please note that this issue was not seen until filename size was 255bytes. Logs for this test is at https://docs.google.com/document/d/1RIPmYgoqAfmsvUEjhNOziYUeITstbAKqY815fcFUhrw/edit?tab=t.0

Set filename size to 256bytes
-----------------------------

[root@ceph-sumar-fscrypt-az0v8f-node6 fuse_sv1]# mv testdir1/abcdefghijklmnopqrstuvwxyz01234567890_.@com+abcdefghijklmnopqrstuvwxyz01234567890_.@com#%-xw_abcdefghijklmnopqrstuvwxyz01234567890_.@com+abcdefghijklmnopqrstuvwxyz01234567890_.@com#%-xwaaaaaaaaaaaaaaaaaaaaaaaaa01234567890_.@com#%-xwaaaaaaaaaaaaaa testdir1/abcdefghijklmnopqrstuvwxyz01234567890_.@com+abcdefghijklmnopqrstuvwxyz01234567890_.@com#%-xw_abcdefghijklmnopqrstuvwxyz01234567890_.@com+abcdefghijklmnopqrstuvwxyz01234567890_.@com#%-xwaaaaaaaaaaaaaaaaaaaaaaaaa01234567890_.@com#%-xwaaaaaaaaaaaaaaa

[root@ceph-sumar-fscrypt-az0v8f-node6 fuse_sv1]# echo -n testdir1/abcdefghijklmnopqrstuvwxyz01234567890_.@com+abcdefghijklmnopqrstuvwxyz01234567890_.@com#%-xw_abcdefghijklmnopqrstuvwxyz01234567890_.@com+abcdefghijklmnopqrstuvwxyz01234567890_.@com#%-xwaaaaaaaaaaaaaaaaaaaaaaaaa01234567890_.@com#%-xwaaaaaaaaaaaaaaa | wc -c
256

Perform fscrypt lock and verify encryption of filename
------------------------------------------------------

[root@ceph-sumar-fscrypt-az0v8f-node6 fuse_sv1]# fscrypt lock testdir1/
"testdir1/" is now locked.

[root@ceph-sumar-fscrypt-az0v8f-node6 fuse_sv1]# ls -l testdir1/
-rw-r--r--. 1 root     root             9 Apr 25 09:21 i7mz,1d9qlRiyqZg1tE5Sf99LyLJfIYcgZ34dQU2dTz1MTMrHd7CZy4zVhkCu7BnMkKkl4DeYqXRoB75sl9MVQ2ns1yBtzqsGYtW7Zqztned3e70VBgeVOU5IN01w6g1Z2g9iv5E1VGv8e7HQH7d7Ggd1TasJzhXnsMXEVgJP9FHPBRAXW5ezKW,R,phlACaBSsTckkmTmzMlW9xqy,lvkqEDNLHZfUiyWjXVsSxFh6F6tXf

[root@ceph-sumar-fscrypt-az0v8f-node6 fuse_sv1]# echo -n testdir1/i7mz,1d9qlRiyqZg1tE5Sf99LyLJfIYcgZ34dQU2dTz1MTMrHd7CZy4zVhkCu7BnMkKkl4DeYqXRoB75sl9MVQ2ns1yBtzqsGYtW7Zqztned3e70VBgeVOU5IN01w6g1Z2g9iv5E1VGv8e7HQH7d7Ggd1TasJzhXnsMXEVgJP9FHPBRAXW5ezKW,R,phlACaBSsTckkmTmzMlW9xqy,lvkqEDNLHZfUiyWjXVsSxFh6F6tXf | wc -c
249

[root@ceph-sumar-fscrypt-az0v8f-node6 fuse_sv1]# fscrypt unlock testdir1/
Enter key file for protector "cephfs_key": secret.key
"testdir1/" is now unlocked and ready for use.
[root@ceph-sumar-fscrypt-az0v8f-node6 fuse_sv1]# ls -l testdir1/
ls: cannot access 'testdir1/???': No such file or directory
total 1583333
-?????????? ? ?        ?                ?            ? '???'
-rw-r--r--. 1 root     root             5 Apr 25 09:15  a
-rw-r--r--. 1 root     root      25254625 Apr 15 13:17  ceph-client.1.log
-rw-r--r--. 1 root     root             4 Apr 17 11:09  file
-rw-r--r--. 1 cephuser cephuser      1024 Apr 17 10:32  file1
-rw-r--r--. 1 root     root          1024 Jan  1  1970  file2
-rw-r--r--. 1 root     root     629145600 Apr 17 10:56  file_1g
drwxr-xr-x. 3 root     root             0 Apr 15 13:39  file_dstdir
drwxr-xr-x. 3 root     root             0 Apr 15 13:39  file_srcdir
-rw-r--r--. 1 root     root       9437184 Apr 15 13:37  fio_file_10m.0.0
-rw-r--r--. 1 root     root          1658 Apr 15 13:45  iozone_report.xls
-rw-r--r--. 1 root     root     957096993 Apr 17 11:45  maillog
-rw-------. 1 root     root        388101 Apr 15 13:24  messages
drwxr-xr-x. 2 root     root          8192 Apr 15 13:48  network_shared
-rw-------. 1 root     root            15 Apr 15 13:23  smallfile
lrwxrwxrwx. 1 root     root            46 Apr 17 10:36  symlink -> file1
drwxr-xr-x. 4 root     root      44692440 Apr 15 13:28  thread0
drwxr-xr-x. 4 root     root      42660824 Apr 15 13:28  thread1
-rw-r--r--. 1 root     root             1 Apr 17 11:00  trunc_file