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Now I am doing a project on operating systems and computer security for a my university.
One of the tasks is to place the Windows EFI bootloader on a USB flash drive (not on the main hard drive!);
I hoped that it would be enough to copy the contents of the hidden EFI partition to a USB flash drive, but I ran into unexpected difficulties.
Windows boots fine, yes.
But if I remove the bootable USB flash drive after logging in, three scenarios are possible (on different physical machines the system behaves differently, on virtual machines it also behaves differently. I suppose it depends on the physical USB controller):
1. System immediately crashes wint bsod SYSTEM_THREAD_EXCEPTION_NOT_HANDLED
2. System hangs (doesn't respond to any user input, but responds in the debugger), after 1 minute crashes with bsod INACCESSIBLE_BOOT_DEVICE (without memory dumping!)
3. Everything continues to work fine (Hehe, my personal computer turned out to be a unique device - this behavior appeared only on it)
Having looked at the dump, I found out that in case 1 an access violation occurs due to dereferencing nullpointer in the function and ExNotifyBootDeviceRemoval
In case 2, the problem manifested itself in ExpWaitForBootDevice.
I tried to examine the situation in the debugger, but I didn't achieve significant results.
Which direction should I go?
Has anyone come across a similar one?
Memory dump (for case 1) on GoogleDrive: https://drive.google.com/drive/folders/1Ewd96Gr6wYRPGIfXxKDlYvmjRwQchJr_?usp=sharing
Thank you in advance!
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