On 12/21, Oleg Nesterov wrote: > > Once again, the parent namespace injects the task T after ns->reaper > sees nr_hashed == 1 and returns. Suppose that reaper's parent does > do_wait() and free_pidmap() clears the bit == 1. > > Now, what if T doesn't exit but forks? We must not re-create the > task with pid_nr == 1 in the dead namespace. Normally this can't > happen, RESERVED_PIDS logic in alloc_pidmap() saves us. But it > seems that we need > > - .extra1 = &zero, > + .extra1 = &one, > > in pid_ns_ctl_table. Oh, and another problem, or I am totally confused. T forks and creates the child C1. C1 creates C2. What if C1 exits? It will try to reparent C2 to the dead/freed ns->child_reaper. In short. We shouldn't allow alloc_pid() if ns->child_reaper is dying, I think. nr_hashed == -1 doesn't really work. Oleg. _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/containers
