[Pkg-sysvinit-devel] Bug#687399: sysvinit.postinst fails under debootstrap --variant=fakechroot when /dev/initctl exists

[Roger Leigh]

On Wed, Sep 12, 2012 at 09:03:26AM -0400, Daniel Kahn Gillmor wrote:
> If i have a GNU/Linux system with /dev/initctl present, and i
> debootstrap with --variant=fakechroot as a non-privileged user, the
> debootstrap fails with :
> 
> Setting up sysvinit (2.88dsf-32) ...
> sysvinit: creating /run/initctl
> ln: failed to create symbolic link `/dev/initctl.new': Permission denied
> dpkg: error processing sysvinit (--configure):
>  subprocess installed post-installation script returned error exit status 1
> Setting up e2fsprogs (1.42.5-1) ...
> Errors were encountered while processing:
>  sysvinit
> 
> This appears to be because this stanza is not wrapped in an ischroot test:
> 
>                # Replace old control channel (if present) with symlink
>                 if [ -e "$OLDINITCTL" ]; then
>                         ln -s "$INITCTL" "$OLDINITCTL.new"
>                         mv "$OLDINITCTL.new" "$OLDINITCTL"
>                 fi
> 
> I suspect the same issue might be true for this other stanza later in
> the postinst:
> 
>         # Remove old pipe if present.  No longer in use after re-exec.
>         if [ "$OLDINITCTL" ] && [ -p "$OLDINITCTL" ]
>         then
>                 rm -f "$OLDINITCTL"
>         fi

We should probably wrap all of the restart logic (except the inittab
stuff) in ischroot checks.  Messing with the host's /dev is not
worth risking.  There was a reason why we did it this way though; it
wasn't unintentional.  I'll have to remember the reasoning, since I
don't want to break something else by accident.  Possibly vservers/lxc
or some other chroot-like thing.

However, why is the host's /dev accessible when bootstrapping--it
certainly shouldn't be bind mounted.  Is this something which
fakechroot is doing?


Regards,
Roger

-- 
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