• @[email protected]
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    1 year ago

    You can mount the efi partition, but I don’t think you can usually mount the uefi or bios. I’ve only ever edited vbios, and haven’t done so in quite some time, but I remember needing to clamp the vbios chip. Dunno if motherboards make their bios chips more accessible, but I kinda doubt it.

    Some motherboard support starting bios/uefi updates from a booted OS, so there might be a vector to be found there.

    • @[email protected]
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      11 year ago

      Early true BIOSen were stored on EPROM, which couldn’t be rewritten while on the board, so those were read-only.

      Later BIOSen were often on EEPROM or other chips that could be reflashed while on the board. According to Wikipedia, that started in the mid-1990s. However, you usually needed physical access and/or special software tools to do an overwrite—you couldn’t mount these as a filesystem.

      UEFI is quite different from legacy BIOSen and can be mounted as a filesystem, but how much it can be tampered with varies between implementations and devices.

      So you would have been correct up until about 30 years ago, but not for modern systems.

  • m4
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    61 year ago

    I’m just curious about what software was used to make this image.

  • @[email protected]
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    171 year ago

    Pretty sure you can brick your system real quick using efivarfs

    https://docs.kernel.org/filesystems/efivarfs.html

    some systems dont let you write but some do.

    Theres a similar system i was messing with to read and write the firmware code… reading through this may be informative.

    efivars should let your change any bios/uefi settings if thats what youre looking for.

    • @[email protected]OP
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      1 year ago

      thank you! I think this is what needed to explore
      It is not my level to edit these things, I’m just Linux newbie exploring the possibilities.

      But I still can’t wrap my head over dd not being able to wipe a storage device out, despite being described as a “low level tool that can write zeroes to targets” in the discussion I viewed online.

  • @[email protected]
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    201 year ago

    It resides on the MB itself in a separate chip, so no, although there are probably tools to make it possible.