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vmmdev: return EFAULT when trying to read beyond VM system memory max address
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Authored by antoine on Apr 22 2018, 7:30 AM.

Details

Summary

Currently, when using dd(1) to take a VM memory image, the capture never ends,
reading zeroes when it's beyond VM system memory max address.
Return EFAULT when trying to read beyond VM system memory max address.
With the patch, I'm able to take a memory image from a windows guest with dd(1)
and analyse it with tools like volatility or rekall.

Diff Detail

Repository
rS FreeBSD src repository
Lint
Automatic diff as part of commit; lint not applicable.
Unit
Automatic diff as part of commit; unit tests not applicable.

Event Timeline

antoine created this revision.Apr 22 2018, 7:30 AM
imp accepted this revision.Apr 22 2018, 3:16 PM
This revision is now accepted and ready to land.Apr 22 2018, 3:16 PM
This revision now requires review to proceed.Apr 22 2018, 9:32 PM
grehan accepted this revision.May 14 2018, 7:13 AM

Good to go with the name change.

sys/amd64/include/vmm.h
215 ↗(On Diff #41720)

Can the name for this be changed to vmm_sysmem_maxaddr ?

This revision is now accepted and ready to land.May 14 2018, 7:13 AM
anish accepted this revision.May 14 2018, 7:00 PM
This revision was automatically updated to reflect the committed changes.