On Tue 08-10-19 15:52:59, Christian Brauner wrote: > On Tue, Oct 08, 2019 at 03:36:37PM +0200, Christian Kellner wrote: > > From: Christian Kellner <[email protected]> > > > > The fdinfo file for a process file descriptor already contains the > > pid of the process in the callers namespaces. Additionally, if pid > > namespaces are configured, show the process ids of the process in > > all nested namespaces in the same format as in the procfs status > > file, i.e. "NSPid:\t%d\%d...". This allows the easy identification > > of the processes in nested namespaces. > > > > Signed-off-by: Christian Kellner <[email protected]> > > Yeah, makes sense to me. > Note that if you send the pidfd to a sibling pid namespace NSpid won't > show you anything useful. But that's what I'd expect security wise. You > should only be able to snoop on descendant pid namespaces. > > Please add a test for this to verify that this all works correctly and > then resend. The tests live in tools/testing/selftests/pidfd/ and should > already have most of the infrastructure there. The fdinfo parsing code > should be in samples/pidfd/ which > > For the patch itself: > > Reviewed-by: Christian Brauner <[email protected]> > > You can resend with my Reviewed-by retained if you don't change > anything. Before I see tests I'll hold off on merging this. ;)
This is also forming a new user visible "api" right? So the make sure that linux-api is on the Cc list. And one minore note. The ifdefery is just ugly, could you just make it a separate function with ifdef hidden inside? -- Michal Hocko SUSE Labs
