On 8/3/25 14:54, Thomas Schmitt wrote:
Hi,
David Christensen wrote:
Beware that the Debian installer (d-i) can change the contents of the USB
flash drive when it runs (!).
I am not aware that the Debian installer writes into the byte range
of the ISO 9660 filesystem.
The ISO 9660 filesystem itself is quite safe from being overwritten.
But MS-Windows or the boot firmware might decide to add files to
the EFI partition which is advertised by the partition table in the
System Area of the ISO filesystem.
I reported the above on this list sometime in the past (few years?), but am
unable to locate the thread at this time. I seem to recall the report was
confirmed, but the details were not where I had guessed.
Possibly
https://lists.debian.org/debian-user/2024/04/msg00040.html
to which i replied in
https://lists.debian.org/debian-user/2024/04/msg00045.html
and pointed to
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1056998
Time is circular ... or rather Jeremy Bearimy.
I have burned my most recent d-i images to CD-R discs
I heartfully support the use of optical media. :))
Have a nice day :)
Thomas
Thank you, Thomas, for finding that. So, I AIUI the d-i does not modify
the USB flash drive, but the motherboard firmware can (BIOS/EFI/UEFI)
and some operating systems can. The result is that the ISO checksum and
the USB flash drive checksum will differ. So, verification of the USB
flash drive must be done immediately after burning and later checksums
are not meaningful.
David
