Bug#989078: several SIGABRT in containers

[Simon Richter]

Hi Michael,

> >To reproduce, build the Debian systemd package inside a docker container,
> >e.g. using

> Is this specific to docker containers / your docker setup?

It seems to be happening under Docker specifically, it runs fine on bare
metal and inside KVM, but that's not where I can run CI builds.

The Docker setup is "apt install docker.io" inside KVM, that shouldn't be
too exotic. I can retry with Docker on bare metal if you believe that
helps.

> docker doesn't often play nice when it comes to systemd, so I
> wouldn't be too surprised, if there are some hickups regarding
> running systemd inside docker.

I'm not running systemd itself inside the container -- this is just an
application querying libudev for a list of devices, and glibc running into
an assertion because it is given a wrong pointer in a realloc().

In my stacktrace, the oldmem parameter to realloc is 0x7f242583b378, which
is in the area behind the mapping for libudev1.so (you can see the
addresses of the libudev functions are around 0x7f24256_____), so it seems
a pointer into the BSS area of libudev1 is given to realloc() here.

So this seems to be a weakness in the sysfs parser in libudev1, or one of
the utility functions it uses, that is exposed when run under Docker.

   Simon