#1056378 sshfs: cannot use setuid= and drop_privileges from mount as sshfs mount helper seem to not use FUSE3

Package:
sshfs
Source:
sshfs
Description:
filesystem client based on SSH File Transfer Protocol
Submitter:
Christoph Anton Mitterer
Date:
2023-11-22 01:00:03 UTC
Severity:
normal
#1056378#5
Date:
2023-11-22 00:57:19 UTC
From:
To:
Hey.

The following problem persits also in unstable.

Doing the following fails:
# mount foo.example.org:/ /mnt -t fuse.sshfs -o setuid=someUser,furtherOptions
fuse: unknown option(s): `-o setuid=someUser'

Whereas it does work if one calls e.g.:
/usr/sbin/mount.fuse3 foo.example.org:/ /mnt -t fuse.sshfs -o setuid=someUser,furtherOptions

The problem seems to be that the setuid= and drop_privileges work only when called via FUSE3
(see mount.fuse(8)) but sshfs’ mount helpers (which mount(1) calls):
   /usr/sbin/mount.fuse.sshfs
   /usr/sbin/mount.sshfs
which are symlinks to:
   /usr/bin/sshfs
seem to not use FUSE3 (despite the binary being linked against libfuse3).

Just using /usr/sbin/mount.fuse3 is no real alternative either, as e.g. systemd
uses simply `mount` for .mount units.


Would be nice if this could be fixed (and backported to bookworm).

Thanks,
Chris.