- ret = -EPERM;
- pcred = __task_cred(p);
- /* If victim is in different user_ns, then uids are not
- comparable, so we must have CAP_SYS_PTRACE */
- if (cred->user->user_ns != pcred->user->user_ns) {
- if (!ns_capable(pcred->user->user_ns, CAP_SYS_PTRACE))
- goto err_unlock;
- goto ok;
- }
- /* If victim is in same user_ns, then uids are comparable */
- if (cred->euid != pcred->euid &&
- cred->euid != pcred->uid &&
- !ns_capable(pcred->user->user_ns, CAP_SYS_PTRACE))
- goto err_unlock;
-ok:
- head = p->compat_robust_list;
- rcu_read_unlock();