smb: server: avoid double-free in smb_direct_free_sendmsg after smb_direct_flush_send...

smb: server: avoid double-free in smb_direct_free_sendmsg after smb_direct_flush_send_list()

smb_direct_flush_send_list() already calls smb_direct_free_sendmsg(),
so we should not call it again after post_sendmsg()
moved it to the batch list.

Reported-by: Ruikai Peng <ruikai@pwno.io>
Closes: https://lore.kernel.org/linux-cifs/CAFD3drNOSJ05y3A+jNXSDxW-2w09KHQ0DivhxQ_pcc7immVVOQ@mail.gmail.com/
Fixes: 34abd408c8ba ("smb: server: make use of smbdirect_socket.send_io.bcredits")
Cc: stable@kernel.org
Cc: Steve French <smfrench@gmail.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: Ruikai Peng <ruikai@pwno.io>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Cc: security@kernel.org
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Acked-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Tested-by: Ruikai Peng <ruikai@pwno.io>
Signed-off-by: Steve French <stfrench@microsoft.com>