Index: sys/kern/kern_sig.c
===================================================================
RCS file: /var3/mirrors/cvs/openbsd/cvs/src/sys/kern/kern_sig.c,v
retrieving revision 1.126
diff -u -r1.126 kern_sig.c
--- sys/kern/kern_sig.c	11 Jul 2011 15:40:47 -0000	1.126
+++ sys/kern/kern_sig.c	17 Sep 2011 06:27:26 -0000
@@ -61,6 +61,7 @@
 #include <sys/pool.h>
 #include <sys/ptrace.h>
 #include <sys/sched.h>
+#include <sys/syslog.h>
 
 #include <sys/mount.h>
 #include <sys/syscallargs.h>
@@ -1300,6 +1301,45 @@
 void
 sigexit(struct proc *p, int signum)
 {
+	const struct process *parent_ps;
+
+	switch (signum) {
+	case 0:
+	case SIGKILL:
+	case SIGINT:
+	case SIGTERM:
+	case SIGALRM:
+	case SIGSTOP:
+	case SIGTTIN:
+	case SIGTTOU:
+	case SIGTSTP:
+	case SIGHUP:
+	case SIGUSR1:
+	case SIGUSR2:
+	case SIGPIPE:
+		break;
+	default:
+		parent_ps = p->p_p->ps_pptr;
+		if (parent_ps != NULL) {
+			log(LOG_INFO,
+			    "signal %d received by (%.32s:%d) UID(%lu) "
+			    "EUID(%lu), parent (%.32s:%d) UID(%lu) EUID(%lu)\n",
+			    signum, p->p_comm, p->p_pid,
+			    (unsigned long) p->p_cred->p_ruid,
+			    (unsigned long) p->p_ucred->cr_uid,
+			    parent_ps->ps_mainproc->p_comm,
+			    parent_ps->ps_mainproc->p_pid,
+			    (unsigned long) parent_ps->ps_cred->p_ruid,
+			    (unsigned long) parent_ps->ps_cred->pc_ucred->cr_uid);
+		} else {
+			log(LOG_INFO,
+			    "signal %d received by (%.32s:%d) UID(%lu) "
+			    "EUID(%lu), orphan\n",
+			    signum, p->p_comm, p->p_pid,
+			    (unsigned long) p->p_cred->p_ruid,
+			    (unsigned long) p->p_ucred->cr_uid);
+		}
+	}
 	/* Mark process as going away */
 	atomic_setbits_int(&p->p_flag, P_WEXIT);