cifs: Add fallback for SMB2 CREATE without FILE_READ_ATTRIBUTES

Some operations, like WRITE, does not require FILE_READ_ATTRIBUTES access.

So when FILE_READ_ATTRIBUTES is not explicitly requested for
smb2_open_file() then first try to do SMB2 CREATE with FILE_READ_ATTRIBUTES
access (like it was before) and then fallback to SMB2 CREATE without
FILE_READ_ATTRIBUTES access (less common case).

This change allows to complete WRITE operation to a file when it does not
grant FILE_READ_ATTRIBUTES permission and its parent directory does not
grant READ_DATA permission (parent directory READ_DATA is implicit grant of
child FILE_READ_ATTRIBUTES permission).

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
This commit is contained in:
Pali Rohár 2024-12-09 20:44:23 +01:00 • committed by Steve French
commit e255612b5e