On 8 July 2013 21:08, Robin Humble <rjh+luv@cita.utoronto.ca> wrote:

>It also needs to provide dummy access to any memory cards too -- or at
>the very least chroot type access to data areas so as to limit every app
>to only have the possibility to read/write it's own data.

CyanogenMod (or maybe even standard Android) already has:
Settings -> Developer options -> Protect SD card
"Apps must request permission to read SD card"

which isn't great as it's not limiting them to one sdcard directory or
anything, but OTOH if you have a photo editing app of some sort then
you actually want it to be able to read your directories full of photos...

My understanding:

sdcard permissions is that it was designed around the premise that you would use the sdcard to store photos, music, etc.

Unfortunately, it is being used for much more then just storing photos, music, etc. For good reasons and bad reasons. In fact it is pretty much at the point I don't have a clue what all these files and directories are on my SD card are, what will break if I try to delete them, what the privacy implications are if these are leaked, or what bad things might occur if an app alters these files without my knowledge.

Some apps try to use the sd card as a work around to the old problem of / not being big enough, so they store large files/cache files on sdcard instead. It is also possible to store apps on sdcard, I don't think the security implications of doing this are well known.

Hence not only is there more applications that require sd card access then anticipated, there is also more private data being stored on the sd card then anticipated.

Everything under / is carefully security controlled, not so for sdcard.

As I said earlier, I can of worms....