Re: [PATCH ghak25 v2 0/9] Address NETFILTER_CFG issues

There were questions about the presence and cause of unsolicited syscall events in the logs containing NETFILTER_CFG records and sometimes unaccompanied NETFILTER_CFG records. During testing at least the following list of events trigger NETFILTER_CFG records and the syscalls related (There may be more events that will trigger this message type.): init_module, finit_module: modprobe setsockopt: iptables-restore, ip6tables-restore, ebtables-restore unshare: (h?)ostnamed clone: libvirtd The syscall events unsolicited by any audit rule were found to be caused by a missing !audit_dummy_context() check before creating a NETFILTER_CFG record and issuing the record immediately rather than saving the information to create the record at syscall exit. Check !audit_dummy_context() before creating the NETFILTER_CFG record. The vast majority of unaccompanied records are caused by the fedora default rule: "-a never,task" and the occasional early startup one is I believe caused by the iptables filter table module hard linked into the kernel rather than a loadable module. The !audit_dummy_context() check above should avoid them. A couple of other factors should help eliminate unaccompanied records which include commit cb74ed278f80 ("audit: always enable syscall auditing when supported and audit is enabled") which makes sure that when audit is enabled, so automatically is syscall auditing, and ghak66 which addressed initializing audit before PID 1. Ebtables module initialization to register tables doesn't generate records because it was never hooked in to audit. Recommend adding audit hooks to log this. Table unregistration was never logged, which is now covered. Seemingly duplicate records are not actually exact duplicates that are caused by netfilter table initialization in different network namespaces from the same syscall. Recommend adding the network namespace ID (proc inode and dev) to the record to make this obvious (address later with ghak79 after nsid patches). See: https://github.com/linux-audit/audit-kernel/issues/25 See: https://github.com/linux-audit/audit-kernel/issues/35 See: https://github.com/linux-audit/audit-kernel/issues/43 See: https://github.com/linux-audit/audit-kernel/issues/44