On Fri, May 10, 2019 at 03:46:56PM +0200, Thomas Schmitt wrote: > Hi, > > Florian Pelz wrote: > > I would like to test but on this bootable German Windows 10 > > 32-bit+64-bit USB install medium, the content is different. How would > > I find the offset in the USB image (you call it offset 454) which I > > should zero out to break Windows? > > That would be offset 454 in the EFI boot image: Start LBA field of MBR > partition 1. > > You may learn the block address of the image from xorriso: > > xorriso -indev "$ISO" -report_el_torito plain 2>/dev/null \ > | grep 'El Torito boot img : .* UEFI' > > should say something like > > El Torito boot img : 2 UEFI y none 0x0000 0x00 1 515 >
This is not an install ISO but a USB install medium. The USB drive was written by the Windows Media Creation Tool. Copying instead a Windows ISO created by the Windows Media Creation Tool to a USB drive does *not* yield a bootable USB drive; it does not even boot on other computers. So mine is a USB drive already, not an ISO image. I do: $ sudo xorriso -indev "stdio:/dev/sdb" -report_el_torito plain GNU xorriso 1.5.0 : RockRidge filesystem manipulator, libburnia project. xorriso : NOTE : Loading ISO image tree from LBA 0 libisoburn: WARNING : No ISO 9660 image at LBA 0. Creating blank image. Drive current: -indev 'stdio:/dev/sdb' Media current: stdio file, overwriteable Media status : is written , is closed Media summary: 1 session, 3932160 data blocks, 7680m data, 0 free Volume id : 'ISOIMAGE' xorriso : NOTE : No El Torito information was loaded Apparently it is wrong to look at such Windows 10 USB media and I should rather look at older Windows installation media. I will try to procure a Windows 7 install ISO. I will report back tomorrow. Regards, Florian _______________________________________________ Grub-devel mailing list Grub-devel@gnu.org https://lists.gnu.org/mailman/listinfo/grub-devel
