Linux supports many obsolete address families, which are usually available in
common distro kernels, but they are less likely to be properly audited and
may have security issues
This blocks all socket families in the socket (and socketcall where applicable) syscall
except
- AF_UNIX - Unix domain sockets
- AF_INET - IPv4
- AF_INET6 - IPv6
- AF_NETLINK - Netlink sockets for communicating with the ekrnel
- AF_PACKET - raw sockets, which are only allowed with CAP_NET_RAW
All other socket families are blocked, including Appletalk (native, not
over IP), IPX (remember that!), VSOCK and HVSOCK, which should not generally
be used in containers, etc.
Note that users can of course provide a profile per container or in the daemon
config if they have unusual use cases that require these.
Signed-off-by: Justin Cormack <justin.cormack@docker.com>
Until we can support existing behaviour with `sudo` disable
ambient capabilities in runc build.
Add tests that non root user cannot use default capabilities,
and that capabilities are working as expected.
Test for #27590
Update runc.
Signed-off-by: Justin Cormack <justin.cormack@docker.com>
While testing #24510 I noticed that 32 bit syscalls were incorrectly being
blocked and we did not have a test for this, so adding one.
This is only tested on amd64 as it is the only architecture that
reliably supports 32 bit code execution, others only do sometimes.
There is no 32 bit libc in the buildpack-deps so we cannot build
32 bit C code easily so use the simplest assembly program which
just calls the exit syscall.
Signed-off-by: Justin Cormack <justin.cormack@docker.com>
This results in a significant time savings during repeated builds (since we don't have to re-download gcc for every test run).
Signed-off-by: Andrew "Tianon" Page <admwiggin@gmail.com>
