OS-5440 pfexec and the case of the missing error message
Reviewed by: Joshua M. Clulow <jmc@joyent.com>
Reviewed by: Patrick Mooney <patrick.mooney@joyent.com>

*** 37,46 ****
--- 37,48 ----
  #include <sys/systm.h>
  #include <sys/sysmacros.h>
  #include <sys/pathname.h>
  #include <sys/varargs.h>
  #include <sys/zone.h>
+ #include <sys/cmn_err.h>
+ #include <sys/sdt.h>
  #include <netinet/in.h>
  
  #define ROUNDUP(a, n) (((a) + ((n) - 1)) & ~((n) - 1))
  
  static kmutex_t klpd_mutex;
*** 858,869 ****
          mutex_enter(&myzone->zone_lock);
          if ((pfd = myzone->zone_pfexecd) != NULL)
                  klpd_hold(pfd);
          mutex_exit(&myzone->zone_lock);
  
!         if (pfd == NULL)
                  return (0);
  
          if (pfd->klpd_door_pid == curproc->p_pid) {
                  klpd_rele(pfd);
                  return (0);
          }
--- 860,876 ----
          mutex_enter(&myzone->zone_lock);
          if ((pfd = myzone->zone_pfexecd) != NULL)
                  klpd_hold(pfd);
          mutex_exit(&myzone->zone_lock);
  
!         if (pfd == NULL) {
!                 DTRACE_PROBE2(pfexecd__not__running,
!                     zone_t *, myzone, char *, rpnp->pn_path);
!                 uprintf("pfexecd not running; pid %d privileges not "
!                     "elevated\n", curproc->p_pid);
                  return (0);
+         }
  
          if (pfd->klpd_door_pid == curproc->p_pid) {
                  klpd_rele(pfd);
                  return (0);
          }
*** 894,903 ****
--- 901,913 ----
                  case EBADF:
                          /* FALLTHROUGH */
                  case EINTR:
                          /* FALLTHROUGH */
                  default:
+                         DTRACE_PROBE4(pfexecd__failure,
+                             int, dres, zone_t *, myzone,
+                             char *, rpnp->pn_path, klpd_reg_t *, pfd);
                          goto out;
                  }
          }
  
          prp = (pfexec_reply_t *)da.rbuf;