xnu-2050.22.13.tar.gz

[apple/xnu.git] / bsd / kern / kern_event.c

diff --git a/bsd/kern/kern_event.c b/bsd/kern/kern_event.c
index ee3d66b09df04f6113ca0ba45aaf7e0dc9a1a7c1..ba269074ac91fb5abf3b93b41e22bfc83f711fb7 100644 (file)
--- a/bsd/kern/kern_event.c
+++ b/bsd/kern/kern_event.c
@@ -471,7 +471,6 @@ static int
 filt_procattach(struct knote *kn)
 {
        struct proc *p;
-       pid_t selfpid = (pid_t)0;
 
        assert(PID_MAX < NOTE_PDATAMASK);
        
@@ -483,15 +482,22 @@ filt_procattach(struct knote *kn)
                return (ESRCH);
        }
 
-       if ((kn->kn_sfflags & NOTE_EXIT) != 0) {
-               selfpid = proc_selfpid();
-               /* check for validity of NOTE_EXISTATUS */
-               if (((kn->kn_sfflags & NOTE_EXITSTATUS) != 0) && 
-                       ((p->p_ppid != selfpid) && (((p->p_lflag & P_LTRACED) == 0) || (p->p_oppid != selfpid)))) {
+       const int NoteExitStatusBits = NOTE_EXIT | NOTE_EXITSTATUS;
+
+       if ((kn->kn_sfflags & NoteExitStatusBits) == NoteExitStatusBits)
+               do {
+                       pid_t selfpid = proc_selfpid();
+
+                       if (p->p_ppid == selfpid)
+                               break;  /* parent => ok */
+
+                       if ((p->p_lflag & P_LTRACED) != 0 &&
+                           (p->p_oppid == selfpid))
+                               break;  /* parent-in-waiting => ok */
+
                        proc_rele(p);
-                       return(EACCES);
-               }
-       }
+                       return (EACCES);
+               } while (0);
 
        proc_klist_lock();