Messages in this thread | | | Date | Sun, 25 Jan 2015 13:36:33 +0100 | From | Alexander Holler <> | Subject | Re: [PATCH v2] modsign: use shred to overwrite the private key before deleting it |
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Am 25.01.2015 um 13:24 schrieb Alexander Holler: > Am 25.01.2015 um 13:08 schrieb Richard Weinberger: >> >> Or add support for the "s" chattr to major filesystems. >> > And change the manpage for the 's' attribute to change the "overwriting > with zero" with some other wording. > > But thanks for the hint. I wasn't aware of that bit (maybe because it's > still useless on most filesystems). > > But the above silly instruction might still help in implementing support > for the 's' attribute. > > Also I wonder what happens if you delete a file with such an attribute > on e.g. an SSD. I assume the user just gets a false positive that the > file is deleted, which isn't much different to what nowadays happens and > doesn't therefor really help. > > So maybe shred should first set the 's' attribute before calling unlink > on that file (if it doesn't already do it). I will look at it and send a > patch if necessary. It's at least a small bit where I can help. ;)
And the manpage for chattr doesn't explain what should happen if a file with the 's' attrribute is changed. A reasonable answer to that is that the old contents, if not changed by overwriting them, should be deleted/zeroed too.
Regards,
Alexander Holler
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