Can sloth support arm32 programs compiled by ndk?

[Po1lux]

Hi,I want to modify your project to test the arm32 program, I copy the /system/ from a rooted Android device into resources/rootfs directory as you mentioned in the usage, but I got the error as blow:
libc: error getting old personality value: Operation not permitted.

I used the unmodified qemu to test and the same error occurred. So the error comes from qemu-arm. I searched for this error and found that the error was in the linker：
http://androidxref.com/6.0.0_r1/xref/bionic/libc/bionic/libc_init_common.cpp#__initialize_personality

personality(0xffffffff); probability means to get the current process execution domain value, it seems that in the qemu-arm it returns -1. So I debug the qemu-arm, the relevant value in qemu is stored in info->personality, but until it runs to cpu_loop, this value is all 0. It may also be that the linker from the mobile phone does not have permission to obtain the value in qemu-arm.

I am confused why the aarch64 program compiled by ndk can be run directly in qemu-aarch, but the arm program compiled by ndk cannot be run in qemu-arm.

would you mind to give me some ideals? This problem has bothered me for a long time.

[ant4g0nist]

Hey!
Looks like the personality syscall is failing.

1. Are you running inside Docker?
2. If so, could you please try running docker with --privileged

Also, could you share on which host you are trying to do this?

[Po1lux]

All operations are done in the docker environment you provide: ubuntu 20.04 x86_64

[ant4g0nist]

okay, can you try running docker with --privileged?

[Po1lux]

Yes, it works! Thanks! I'm just trying to figure out why it works in aarch64 directly. I replied via email, but it doesn’t seem to be displayed here

[ant4g0nist]

Perfect!

So, personality is blocked as part of the seccomp profile! the execution might fail for 64-bit also, if some binary executes that syscall!

Check the section Significant syscalls blocked by the default profile here https://docs.docker.com/engine/security/seccomp/

[Po1lux]

thanks! so nice you are :)

[ant4g0nist]

haha thank you :) let me know how it goes. all the best \m/