On Tue, Sep 24, 2019 at 12:20:01PM -0300, Carlos Neira wrote: > Currently bpf_get_current_pid_tgid(), is used to do pid filtering in bcc's > scripts but this helper returns the pid as seen by the root namespace which is > fine when a bcc script is not executed inside a container. > When the process of interest is inside a container, pid filtering will not work > if bpf_get_current_pid_tgid() is used. > This helper addresses this limitation returning the pid as it's seen by the current > namespace where the script is executing. > > In the future different pid_ns files may belong to different devices, according to the > discussion between Eric Biederman and Yonghong in 2017 Linux plumbers conference. > To address that situation the helper requires inum and dev_t from /proc/self/ns/pid. > This helper has the same use cases as bpf_get_current_pid_tgid() as it can be > used to do pid filtering even inside a container. > > Signed-off-by: Carlos Neira <cneirabustos@xxxxxxxxx> > > Carlos Neira (4): > fs/nsfs.c: added ns_match > bpf: added new helper bpf_get_ns_current_pid_tgid > tools: Added bpf_get_ns_current_pid_tgid helper > tools/testing/selftests/bpf: Add self-tests for new helper. self tests > added for new helper bpf-next is currently closed due to merge window. Please resubmit once back open, thanks.
