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Hi,

On 2012-09-08 23:49, Brian Carlstrom wrote:
> On Fri, Sep 7, 2012 at 2:31 PM, Sebastian Bachmann
> <[email protected]> wrote:
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>> 
>> okay, but thats not very good?
>> 
>> so the dex doc says about the checksum the following: adler32
>> checksum of the rest of the file (everything but magic and this
>> field); used to detect file corruption
>> 
>> so why the dalivkvm does not check it? i mean ok, it takes some
>> time but what if there is a real corruption?
> 
> I assume because it takes time. suppose there was a problem in 
> /system, the files are readonly and better not be wrong or else 
> something more serious is wrong that can be fixed after detecting
> the problem. if there is a problem with an app in /data, the user
> can uninstall/reinstall. i do think package manager takes other
> steps to ensure there aren't partially updated files. if the
> original APK itself is wrong, the app author is just hurting
> themselves. if your point is that malware is taking valid apks and
> messing with them and resulting in invalid checksums, it might be
> an interesting signal, but if we fixed that, they'd just change
> their tools to just fix the checksum. it's not adding anything
> really.

ah okay i see!

> 
>> so what could probably be done with this? A wrong checksum just
>> forces a creation of a new odex? nothing more?
> 
> not a wrong checksum, just a changed checksum.

yes i meant that :)

thank you!
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