Stuck at 'Analyzing gaps' for a suspiciously long time.

[Raphtaliyah]

Describe the bug
Ghidra (11.2.*) spends a suspiciously long time at the 'Analyzing gaps' step when analysing a 9 MB 32 bit windows executable (the same executable from cmu-sei/pharos#274). At first I didn't want to report this as a bug because "surely it just takes this long" until I saw a similar issue (#65) where someone was analysing a larger executable for 9 hours and after a fix it end up being 640 seconds so I assume something has to be wrong here as well and it shouldn't take this long.

Looking at the logs (of which I have 2 GBs of (spread across 29 files) just from this!) it's mostly Skipping address, searching for any of the addresses shows around 67 matches/file. Looking for anything not Skipping address is Created alignment at:, the addresses are unique but in between them there is this repeating:

2024-11-05 22:56:10 DEBUG (X86ImproverStrategy) Disassembly status at 006c7983 was: Disassembler requires a start which is an undefined code unit  
2024-11-05 22:56:10 DEBUG (X86ImproverStrategy) Disassembly status at 006c7993 was: Disassembler requires a start which is an undefined code unit  
2024-11-05 22:56:10 DEBUG (X86ImproverStrategy) Disassembly status at 006c7aba was: Disassembler requires a start which is an undefined code unit  
2024-11-05 22:56:10 DEBUG (X86ImproverStrategy) Disassembly status at 00709d14 was: Disassembler requires a start which is an undefined code unit  
2024-11-05 22:56:10 DEBUG (X86ImproverStrategy) Disassembly status at 007819f0 was: Disassembler requires a start which is an undefined code unit 

Always the same address.

There is nothing else in the log files (other than when I stopped it), Kaiju Disassembly Improvements ran for 14 hours and did 26880 iterations.

To Reproduce
Steps to reproduce the behavior:

1. Start analysis on the executable with the default settings with WindowsPE x86 Propagate External Parameters and Decompiler Parameter ID (with a really high timeout) enabled.
2. Wait a lot...

Expected behavior
Less waiting? (Unless this isn't a bug and is expected behaviour...)

Desktop (please complete the following information):

• OS: Fedora Linux 41 (KDE)

[sei-eschwartz]

Thanks for reporting. This definitely sounds like a bug to me. Did this happen to be for the same executable that you already shared with me?

[Raphtaliyah]

Yes, it's the same!

[sei-eschwartz]

Without disassembly improvements:

2024-11-13	14:04:54	INFO	(AutoAnalysisManager) -----------------------------------------------------
			ASCII Strings 2.798 secs
			Apply Data Archives 0.325 secs
			Call Convention ID 0.199 secs
			Call-Fixup Installer 0.633 secs
			Create Address Tables 1.459 secs
			Create Address Tables - One Time 10.360 secs
			Create Function 3.597 secs
			Data Reference 2.287 secs
			Decompiler Switch Analysis 62.805 secs
			Decompiler Switch Analysis - One Time 788.057 secs
			Demangler Microsoft 0.342 secs
			Disassemble 7.303 secs
			Disassemble Entry Points 2.235 secs
			Disassemble Entry Points - One Time 0.002 secs
			Embedded Media 0.287 secs
			External Entry References 0.002 secs
			Function ID 5.857 secs
			Function Start Pre Search 0.061 secs
			Function Start Search 2.144 secs
			Function Start Search After Code 2.150 secs
			Function Start Search After Data 1.366 secs
			Function Start Search delayed - One Time 0.049 secs
			Kaiju Function Hashing 28.663 secs
			Non-Returning Functions - Discovered 8.774 secs
			Non-Returning Functions - Known 0.005 secs
			PDB Universal 0.008 secs
			Reference 2.359 secs
			Scalar Operand References 6.959 secs
			Shared Return Calls 1.789 secs
			Stack 23.121 secs
			Subroutine References 2.132 secs
			Subroutine References - One Time 0.088 secs
			Windows x86 PE Exception Handling 5.720 secs
			Windows x86 PE RTTI Analyzer 17.349 secs
			Windows x86 Thread Environment Block (TEB) Analyzer 0.012 secs
			WindowsResourceReference 0.961 secs
			X86 Function Callee Purge 26.814 secs
			x86 Constant Reference Analyzer 22.840 secs
			-----------------------------------------------------
			Total Time 1041 secs