Bug#821793: fusermount should not attempt to use /etc/mtab

Ximin Luo infinity0 at debian.org
Wed Nov 16 18:48:00 UTC 2016

Nikolaus Rath:
> Can someone clarify if this is a bug in upstream fuse (which assumes
> existence of /etc/mtab) or in the software that creates the chroots
> without /etc/mtab?
> If someone can give me a decent source that states that /etc/mtab does
> not need to exist, I'll be happy to change fusermount accordingly. 

Hi Nikolaus,

It's hard to find an "authoritative" source for this but:

"It does not matter to mount if there are duplicated entries nor to umount if a name cannot be found."

"Note that the fstab and mtab files are maintained on a system by convention. It is possible for the files not to exist or not to be consistent with what is really mounted or available to mount, if the system’s administration policy allows it. But programs that mount and unmount filesystems typically maintain and use these files as described herein."

"The definitive list of mounted filesystems in in /proc/mounts... [etc why /etc/mtab sometimes differs]".

In other words it's generally understood that /etc/mtab might not reflect "reality" and so fusermount shouldn't be relying on it to make decisions.


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