EXT: don't reserve any block for root #743
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There is only root in dom0, and `df` erroneously substracts the default 5% of disk space as "reserved for root", which is just meaningless here. Would be worth: - doing the same for all FileSR types - some way to get `tune2fs -m 0` run on existing SR to make them even
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As you say, all access is performed as root anyway so I'm not sure what actual difference this will make? |
Contributor
This assertion is not correct for XenServer. In XenServer's dom0 various processes run as different users (e.g. chrony, pvsproxy, QEMU, swtpm, ...). A vulnerability without a privilege escalation in one of those components could then more easily lead to a DoS if the reserve is removed, i.e. it would be a loss of defence-in-depth. Whether this is important enough to keep the reserve is debatable but the discussion at least needs to be had. |
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There is only root in dom0, and
dferroneously substracts the default 5% of disk space as "reserved for root", which is just meaningless here.It could be worth going further with doing the same for all FileSR types, but I thought I'd ask for feedback first.
If this becomes a thing, it could be useful then to find some way to get
tune2fs -m 0run on existing SR to make them even.