Fix abi issue

[KingMahmud]

Compile odex and vdex per the instruction set app uses.
Example :
When an app contains arm7 binaries, it compiles odex and vdex with arm7 instruction set.
I am on Arm64 device and trying to do odex patching an app which only contains arm7 binaries. I patched the odex but seems it didnt work, i troubleshooted a bit and found that there was a created a new folder at oat dir, arm64.
But it should compile odex vdex as arm7 not arm64.
Kindly check out the issue

[giacomoferretti]

Thanks for opening the issue! Can you give me more information to work with?

• App's version
• Android version
• ABI
• Device manufacturer (Pixel, Samsung, etc.)
• ROM (Stock, AOSP, TouchWiz, etc.)
• Original APK and modded apk (optional)
• Logcat (optional)

[KingMahmud]

App's version : 2.0.0 rc 1
Android version : 10
ABI : arm64-v8a, armeabi-v7a
Device manufacturer : Samsung
Rom : Stock
Original APK : use any apk which has armeabi-v7a binaries

[KingMahmud]

https://github.com/giacomoferretti/odex-patcher/blob/main/app/src/main/java/me/hexile/odexpatcher/art/Art.kt

Field : CPU_ABI

It should not be like this as instruction set used by the app we are patching may be different.
Example :
some.apk -> libs/armeabi-v7a/*
In this case even if the device is arm64, the app will run on arm instruction set.

I hope my point is clear.

A possible solution : "base.apk" -> parent file -> + /oat -> arm64 or arm or x86 ...

[giacomoferretti]

Wait, you mean compiled ".so" libraries?

[KingMahmud]

Wait, you mean compiled ".so" libraries?

Yes

[giacomoferretti]

Odex Patcher doesn't touch shared libraries, I don't understand what the problem is.

Can you give me the APK that you have problem with, so I can replicate it and fix it?

[KingMahmud]

Okay here is a dummy apk.
System requirement : arm64 device
via-release_sign.apk.zip

Remove .zip extension and it will be installable

[KingMahmud]

Now try patching the odex, you will see :
Before :
/data/app/mark.via.gp/oat/arm/.oat|.vdex

After :
/data/app/mark.via.gp/oat/ ->
arm64/.oat|.vdex
arm/.oat|.vdex

Here the arm64 folder contains patched oat, while the app uses arm one.
Reason : the app is using arm native binaries and because of that it will compile oat to same.

[KingMahmud]

I would have sent a PR with fix for these issues but the project is in kotlin and i am a java person😄.
I am not that good with kotlin, so i decided not to ruin your code.

[giacomoferretti]

Now try patching the odex, you will see : Before : /data/app/mark.via.gp/oat/arm/.oat|.vdex

After : /data/app/mark.via.gp/oat/ -> arm64/.oat|.vdex arm/.oat|.vdex

Here the arm64 folder contains patched oat, while the app uses arm one. Reason : the app is using arm native binaries and because of that it will compile oat to same.

I have never encountered such a case, but now I understand better. I will try as soon as possible, thank you!

I would have sent a PR with fix for these issues but the project is in kotlin and i am a java personsmile. I am not that good with kotlin, so i decided not to ruin your code.

Don't worry, currently the code is very messy, so it's not a problem if it's not good, in case I'll fix it later. 😉

[KingMahmud]

Thanks!
I hope there will be a quick fix and update ;)

[giacomoferretti]

I have found the problem and am starting to write the fix. I need to rewrite the ISA "detection".

[KingMahmud]

Yeah, removing dependence on CPU_ABI would fix it.
CPU_ABI doesn't hold any importance except for setting ISA, ISA can be known from :
"base.apk" -> parent file -> + /oat -> arm64 or arm or x86 ...

[giacomoferretti]

I don't want to go that way, because in the rare case that the app is not already optimized, there is no oat folder. I would check if has native lib, like Android does, and if not, fallback to CPU_ABI.

[KingMahmud]

Okay, that seems plausible ;)

[KingMahmud]

Any updates?

[giacomoferretti]

Not yet, I was working on it in September, but now I have to study.

You can check the progress here: https://github.com/giacomoferretti/odex-patcher/tree/dev

It's almost a complete rewrite, because the structure wasn't optimal.

[KingMahmud]

Okay!
Have good time studying :)