`Couldn't re-execute SBCL with proper personality flags (/proc isn't mounted? setuid?)`

[Fabien Snauwaert]

I'm trying to use SBCL for use with pgloader. This is on Ubuntu 16.04 running inside of Docker.

I was able to install SBCL however I got the following warnings during install:

 Setting up binfmt-support (2.1.6-1) ...
 mount: permission denied
 update-binfmts: warning: Couldn't mount the binfmt_misc filesystem on /proc/sys/fs/binfmt_misc.
 invoke-rc.d: could not determine current runlevel
 invoke-rc.d: policy-rc.d denied execution of start.
 Setting up sbcl (2:1.3.1-1ubuntu2) ...
 mount: permission denied
 update-binfmts: warning: Couldn't mount the binfmt_misc filesystem on /proc/sys/fs/binfmt_misc.

And whenever I try to run SBCL, I get `WARNING: Couldn't re-execute SBCL with proper personality flags (/proc isn't mounted? setuid?)`.

(Which turns out to be a blocking issue for pgloader.)

I'm including a minimal case of the issue: a minimal version of a Dockerfile used to reproduce the issue; a log of the compilation of said Dockerfile.

[Fabien Snauwaert (fabien-snauwaert)]

I don't see my attachments. Trying to add them again.

[Fabien Snauwaert (fabien-snauwaert)]

Log of the build of the Dockerfile

[Douglas Katzman (dougk)]

So is or isn't /proc mounted? Inability to mount /proc/sys/fs/binfmt_misc suggests that it isn't.

Until or unless SBCL can deal with address space layout randomization, you're going to have to figure out how to enable its use the personality() system call, which is failing as per the WARNING about "couldn't re-execute".

(It's conceivable that we might already support randomization a little bit better now than when the code in 'src/runtime/linux-os.c' was written. But it assumes that if randomization is present, then it's not going to work at all. I suspect that might not be entirely true, as long as we can acquire memory at a few fixed locations; the dynamic-space is no longer fixed in place)

[Eric Timmons (daewok)]

I use SBCL in Docker extensively. I have a seccomp profile for docker in the slime-docker project that allows SBCL to disable ASLR by enabling the personality syscall [https://github.com/daewok/slime-docker/blob/master/resources/docker-sbcl-seccomp.json]. Just pass it to the `docker run` command.

However, I've used SBCL extensively both with and without this profile and I have yet to run into any issue when running with ASLR. Definitely haven't used every feature of SBCL with ASLR on, but for most things it seems to work well.

[Douglas Katzman (dougk)]

According to your log file, SBCL started, but just printed the warning as an advisory.
If the warning is the problem, honestly I'd suggest commenting it out as a local patch, *or* figure out what it's saying is true: is /proc mounted? If it's lying, then that's a bug. But I suspect it's not lying.
I'm going to resolve this as not a bug. Reopen if I'm mistaken.

[Stas Boukarev (stassats)]

In 133fb4b1ff8c9ed904de86d0db61c5df266a3690.