Linux encryption/luks/pymouth password scripts corruption

Question

I noticed that the bootup scripts that collect the password for full disk encryption on linux (fedora-31) were displaying corrupted text. The kind that looked like binary data being printed at text:

'Forward Password R…uests to Wall Directory Watch'

When I examined those binary chars I found between to the 'R' and the 'uests' three binary chars (e2, 80, a6). When I run those unprintable chars into objdump I get valid opcodes:

0: e2 80 loop 0xffffffffffffff82

2: a6 cmpsb %es:(%rdi),%ds:(%rsi)

I'm really hoping there is a good reason for valid opcodes being embedded in text messages. But considering its happening during the full disk encryption password collector it has me worried.

I've also noticed that others have this same issue. A web search for "Forward Password R..." finds others with the same binary corruption in their bootup logs.

Does anyone know what is going on here?

Answer 1

Relax. Don't panic.

Those "highly suspicious binary bytes" are the UTF-8 representation of U+2026, which is the Ellipsis .... It's just to print exactly that string that you're quoting.
It probably got shortened by an algorithm to make it fit in a preallocated space.

The fact that you can disassemble it into "valid opcodes" does not mean a thing. You tested these three bytes but not the bytes around it – you might be surprised to learn that you can 'disassemble' just about any sequence of bytes, be it a JPEG image, MP3 music, and your log file.