CVE-2026-99114: ksmbd: initialize FileSystemControlFlags in FS_CONTROL_INFORMATION

In the Linux kernel, the following vulnerability has been resolved:

ksmbd: initialize FileSystemControlFlags in FSCONTROLINFORMATION

smb2getinfofilesystem() reports 48 bytes for FSCONTROLINFORMATION, that is the whole of struct smb2fscontrolinfo, but never assigns FileSystemControlFlags. Those four bytes go to the client as they are found in the response buffer.

The buffer is zeroed on allocation, so a standalone request leaks nothing. A compound request can leak: the offset of the next response is advanced by the length pinned for the previous one, so a reply that was written into the buffer and then dropped in favour of the short error response of smb2seterrrsp() stays there, and the next reply is laid over it with only the header cleared.

ksmbd does not implement quota tracking, so report no control flags.