[maemo-users] [maemo-users] Re: Bricked a third time

[From: Eero Tamminen]

Hi,

ext Aniello Del Sorbo wrote:
> Marius Gedminas wrote:
>> On Mon, Feb 12, 2007 at 08:13:47PM +0000, Neil MacLeod wrote:
>>> Richard Pickler wrote:
>>>> The second time, I was installing some packages I built myself, and 
>>>> it crashed, which I could not recover from. (this one I'll take the 
>>>> blame for).
>>> Why should you take the blame? This is a consumer oriented device and 
>>> software installation is promoted as a user feature - it should not 
>>> brick the device, period!
>>
>> I'm pretty sure you can install apps from the tableteer certified
>> repository without bricking the device.
>>
>> It's impossible to prevent packages from other repositories from doing
>> so.  Package installation can runs arbitrary scripts as root, and you
>> can't prevent root from destroying a Linux system.  (Well, maybe if you
>> lock it down with capabilities/SELinux/something else, but it's hard to
>> do so without making unable to do anything useful.)
>>
> 
> Why?
> On the tablet you just install apps. Why should the installer need to be 
> root to do so?
> A properly configured device (as it should have been) should NEVER ask 
> for root permissions.

dpkg runs as root and it installs the packages under root rights.
Badly done package can therefore very easily[1] make the device
go into reboot-loop.

[1] For example by filling the disk in postinst script and not cleaning
     it up, overwriting or removing some required system file etc.


> All programs just copy their own executables and write their own 
> configuration in a file. It can be made in a user writable directory 
> (perhaps in the memory card too [see below]).
> Same holds for libraries.
> 
> I can think of very few .debs (if any) that need to be installed by root 
> on a tablet.
> 
> Speaking about installing apps on the MMC, it would be very easy too.
> I am sure the Maemo Team was faced with such an option and they had to 
> choose between partitioning the SD/MMC (as VFAT can cause a few issues 
> with apps execution, and the apps themselves should deal with execution 
> and configuration files in an unusual path [many do]) or giving away 
> with this option. The chose the latter.
> 
> May be they just postponed it as they would have needed to deal with 
> some stuff, for example what to do if you remove/install an SD (the menu 
> should catch the D-BUS event and remove the external apps from the list 
> and should add them back when the card is inserted and stuff like that).
> 
> But I am sure it would be perfectly feasible and very useful too (the 
> dpkg utility allows it).


	- Eero