> And pardon me, but could you explain to me what the need is for a(n undocumented!) way to gain access to "certain files" on a phone by a remote person ? As far as I can tell there is nothing on a phone a remote person should have access to without the explicit say-so of the owner.
Sweet jesus. The system is not an undocumented way to allow a reomte, third party unauthenticated arbitrary access to your data. It's a system used to allow the modem firmware running on a separate DSP core to save and recall information. Yes, there exists a <b>possibility</b> that a flaw in the modem firmware could allow a third party to command the modem to make IPC requests to the device's host processor to read information and then, potentially, transmit it back. There is no evidence to suggest that such a flaw exists.
> You mean to say that as they all have got similar backdoors (do they ?) its OK ? Strange reasoning
No I don't mean to say all have any backdoors; a backdoor is a camouflaged or otherwise hidden system installed to circumvent access restrictions. This is niether camouflaged nor hidden. It's purpose is not to circumvent access controls. It is not a backdoor.
> Bottom line: A phone which has got RPC file-IO calls from the cellular into the smart part of the phone is at least questionable.
Questionable? Yes, of course. But do not attribute to malice what is adequately explained as incompetence.