Questions tagged [arm]

A family of instruction set architectures based on a RISC architecture developed by British company ARM Holdings. Heavily used in embedded devices such as mobile phones, tablets, set-top boxes, ...

35 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
3
votes
2answers
79 views

Get certain instruction count for multi-architecture binaries

I need to get an ELF binary's total count of Function call instruction conditional jump (branch) instruction The binary could be any CPU architecture, like x64, ARM, MIPS, Motorola 68K, etc. It ...
3
votes
0answers
295 views

Running vmlinux ELF under QEMU

I have a vmlinux ELF file to run under QEMU. My arguments to qemu-system-arm.exe are: The correct -cpu argument. The versatilepb -machine which I'm not sure if it's the right choose, but can't see ...
2
votes
0answers
76 views

Reversing a firmware update for an LG HTS

I'm trying to reverse a firmware update for an LG Home Theater BH7220, and I've hit a brick wall. This HTS has a main chip from LG referred to as "BH7000:1165" in the schematics. The chip has the ...
2
votes
0answers
68 views

When virtual table is not the first element of structure?

Assuming that source code is compiled for ARMv7 architecure using clang (native shared object library for Android, Itanium ABI) what are the cases when virtual table pointer is not the first element ...
2
votes
0answers
92 views

Reverse Engineering Firmware Aether Cone

I have been trying to work out if its possible to reverse engineer the firmware for the Aether Cone. This is a good sound quality WIFI and Bluetooth speaker, but with Aether going bust, there is no ...
2
votes
0answers
397 views

Extracting ARM Boot zImage

I'm trying to analyze the firmware of a system running Linux and connecting various home automation and security devices. Every time it boots, the GM8125 processor running ARMv5TE loads a firmware ...
2
votes
0answers
75 views

Understanding ESIL

I cross-compiled a simple program with the aarch-linux-gnu-gcc compiler for ARM. So the machine is "ARM aarch64". I want to understand a single instruction and it's realization in ESIL. The opcode of ...
2
votes
0answers
978 views

Arm hex firmware reverse

it has been a couple of months that I'm working on the firmware produced by a company that makes (not licensed) gamepad console adapters. One of my goal was to understand how they bypassed (hacked) ...
2
votes
0answers
438 views

Patch ELF (arm): remove constructor segment

I got an ELF shared library with a constructor function that is executed every time the library is loaded: .init_array:00005E5C ; ===================================================================== ...
1
vote
0answers
25 views

Strange behaviour debugging Android ARM binary with gdbserver

I'm trying to run this armv5 binary from OWASP's mobile security guide (validate) using Android Studio's emulator on my x86_64 machine. I'm seeing very weird behaviour and would appreciate any ...
1
vote
0answers
138 views

Extracting firmware image from binary

I have firmware file in .bin format, but I need get firmware.img image file and Kernel uImage file for reflashing bricked device. How can I get these parts? I used Binwalk to extract content, ...
1
vote
0answers
58 views

Debugging arbitrary ARM binary image using IDA and QEMU

i'm new to this and still learning a lot. Now i have managed to download the binary image from an Flash memory out of a unit having an OMAP5912 SoC. The SoC has an ARM9 family CPU core running little ...
1
vote
0answers
111 views

Can you change the architecture in Ghidra after importing?

I've been analyzing an ARMv7 binary for a while and have done a lot of work with it (e.g. labeling functions, creating structs, labeling globals etc.). Unfortunately, I just realized that Ghidra ...
1
vote
0answers
130 views

Simplify two 32 bit expressions into one 64 bit expression in decompilation

I am getting started with Ghidra, and am decompiling a simple program of mine. The platform is Linux (ELF) on ARM. I found in the decompiled code things like: gTime._0_4_ = (undefined4)(time1 >>...
1
vote
0answers
72 views

Help understanding ARM Assembly example code - loops, set flags and code mnemonics

This is the example code: _start: LDR r0, =n LDR r0, [r0] LDR r1, =array1 MOV r2, #0 LDR r4, =array2 loop: LDR r3, [r1], #4 CMP r3, #58 BGT a_point CMP r3, #47 BLT a_point SUB r3, r3, #0x30 STR r3, [...
1
vote
1answer
120 views

Bp on memory access in arm deb

I'm using idapro for arm native debugging (with androidseever) . I'd like to check when a memory data is read by code (what instruction and where). Hardware bp is not possible. How can i do? How to ...
1
vote
0answers
385 views

Patching an ipa (iPhone app) using Hopper Disassembler

I have learned in the past to patch some iOS apps to bypass jailbreak detection. Today, I decided to change the UI elements in the Spotify app on iOS Platform (ios 11). I downloaded a .ipa file of ...
1
vote
0answers
126 views

Why does IDA mark this as end of function?

I'm analyzing a .so file that is a part of an android application. I've stumbled upon this block of code: LOAD:0001B63C sub_1B63C ; CODE XREF: sub_1B628+Cp LOAD:...
1
vote
0answers
133 views

Help identify missing componant for jtag connection

I found JTAG header for ARM (OMAP3x). It's a Cortex 10-pin 0.05" JTAG/SWD Connector. (See http://support.code-red-tech.com/CodeRedWiki/HardwareDebugConnections) I think it's JTAG because PIN#3 and 5 ...
1
vote
0answers
404 views

Elf binary manipulation tool on ARM

Do you know any free tool for binary manipulation elf file on ARM, something like ERESI elfsh for Intel? Purpose - adding instructions into existing binary elf file.
1
vote
0answers
206 views

Calculating branch in arm64

I stumbled across this question here Offset calculation for branch instruction in ARM After understanding all of that, i'm interested in knowing how i can do the same for ARM64/ARMv8 architecture?
1
vote
0answers
242 views

All data in IDA Pro turns into zeros when using QEMU

I'm trying to emulate a snippet of ARM assembly I have in IDA pro using QEMU. However I do not understand the output of the program. When I start debugging the firmware, windows pop up for QEMU. ...
1
vote
0answers
508 views

Determine ARM architecture from IDA plugin

Writing sandbox plugin for IDA (with IDAPython, but that not the case as it seems) to analyze ARM opcodes, I've came upon following issues: 1) How can I distinct specific ARM architecture (e.g. ARMv5,...
1
vote
0answers
429 views

Static binary instrumentation tools for android .so libraries?

I'm trying to statically inject code into an android app. The best way would be to use APKStudio and the like, but there are very harsh restrictions on the device and the app itself, so that apk ...
1
vote
0answers
590 views

crackme binary crashing on Raspberry pi

I was trying out a basic ARM crackme here. Upon running it on my Raspberry pi, it segfaults without giving me any warning. Moreover, I'm unable to set breakpoints anywhere(even on the entry point). Is ...
0
votes
1answer
45 views

How to Modify CBZ Branch in ARM64?

If I want after running the CBZ W0, loc_C5C8 command Run to the ADRP X8,#selRef_curent_version@PAGE command regardless of the condition (in picture), what should I do?
0
votes
0answers
14 views

Building firmware.bin from mtd partitions

Working on reversing current router firmware here and I can't find any sources from the manufacturer for their firmware and toolchain. I wanted to do this approach. firmware.bin is loaded and ...
0
votes
0answers
51 views

Why is U-Boot changing this bit marked as “DO NOT CHANGE”?

While reverse engineering very early hardware initialization code of an old S3C6410 based tablet, I came across an instruction that changes a bit that the user manual (relevant info on pg. 3-50) ...
0
votes
0answers
24 views

LLDB Cannot calculate virtual address from ASLR slide

I am trying to set a breakpoint at an Objective-C method in an iOS app (armv7). I create a toy app, dumped the sections to find the loaded address of the __text section, and calculated the mapped ...
0
votes
0answers
81 views

Why decrement a hex value in assembly code?

I am running a disassembly of a firmware image for a Cortex-M4 and the entry point is doing something strange. EntryPoint: 00001000 db 0x00 ; '.' 00001001 db 0xff ; '.' 00001002 ...
0
votes
0answers
266 views

Disassembling ARM binary

I am trying to disassemble a firmware binary which I am interested in. Yet I don't have much experience in this field, which is why I would like some input from you guys. My current state is that I ...
0
votes
1answer
87 views

Finding function at offset loaded with ADRP/ADD

I have this assembly: ADRP X8, #off_FFFFFFF006F1E960@PAGE ADD X8, X8, #off_FFFFFFF006F1E960@PAGEOFF LDR X0, [X8] ; qword_FFFFFFF0077F08A8 LDR X8, [X0] ...
0
votes
0answers
72 views

Dumping flash from a running Cortex-M

I have a working device with a STM32F405ZGT6 in it. I want to dump the software it runs. As far as I can tell, there's no external flash on the device, so it must be running off of the internal flash....
0
votes
1answer
273 views

Firmware reverse engineering

this question is a follow-up from this previous post: Flash dump binwalk blank, low entropy I need to reverse engineer a firmware from a very secure device. I was able to reverse engineer the PCB ...
-1
votes
2answers
49 views

Edit arm thumb2 intelhex file

I have intelhex file to arm 32 bits thumb 2. I want edit this file add/ change instructions. Looking for easy and free tool (prefer gui windows tool ) to do it please.