To implement seccomp for s390x the following changes are required:
1) seccomp_default: Add s390 compat mode
On s390x (64 bit) we can run s390 (32 bit) programs in 32 bit
compat mode. Therefore add this information to arches().
2) seccomp_default: Use correct flags parameter for sys_clone on s390x
On s390x the second parameter for the clone system call is the flags
parameter. On all other architectures it is the first one.
See kernel code kernel/fork.c:
#elif defined(CONFIG_CLONE_BACKWARDS2)
SYSCALL_DEFINE5(clone, unsigned long, newsp, unsigned long, clone_flags,
int __user *, parent_tidptr,
So fix the docker default seccomp rule and check for the second
parameter on s390/s390x.
3) seccomp_default: Add s390 specific syscalls
For s390 we currently have three additional system calls that should
be added to the seccomp whitelist:
- Other architectures can read/write unprivileged from/to PCI MMIO memory.
On s390 the instructions are privileged and therefore we need system
calls for that purpose:
* s390_pci_mmio_write()
* s390_pci_mmio_read()
- Runtime instrumentation:
* s390_runtime_instr()
4) test_integration: Do not run seccomp default profile test on s390x
The generated profile that we check in is for amd64 and i386
architectures and does not work correctly on s390x.
See also: 75385dc216 ("Do not run the seccomp tests that use
default.json on non x86 architectures")
5) Dockerfile.s390x: Add "seccomp" to DOCKER_BUILDTAGS
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
bf2a577c13