Index: head/usr.bin/diff/pr.c
===================================================================
--- head/usr.bin/diff/pr.c	(revision 335001)
+++ head/usr.bin/diff/pr.c	(revision 335002)
@@ -1,125 +1,126 @@
 /*-
  * Copyright (c) 2017 Baptiste Daroussin <bapt@FreeBSD.org>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer
  *    in this position and unchanged.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
 #include <sys/procdesc.h>
 #include <sys/wait.h>
 
 #include <err.h>
 #include <paths.h>
 #include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
 
 #include "pr.h"
 #include "diff.h"
 #include "xmalloc.h"
 
 #define _PATH_PR "/usr/bin/pr"
 
 struct pr *
 start_pr(char *file1, char *file2)
 {
 	int pfd[2];
 	int pr_pd;
 	pid_t pid;
 	char *header;
 	struct pr *pr;
 
 	pr = xcalloc(1, sizeof(*pr));
 
 	xasprintf(&header, "%s %s %s", diffargs, file1, file2);
 	signal(SIGPIPE, SIG_IGN);
 	fflush(stdout);
 	rewind(stdout);
 	if (pipe(pfd) == -1)
 		err(2, "pipe");
 	switch ((pid = pdfork(&pr_pd, PD_CLOEXEC))) {
 	case -1:
 		status |= 2;
 		free(header);
 		err(2, "No more processes");
 	case 0:
 		/* child */
 		if (pfd[0] != STDIN_FILENO) {
 			dup2(pfd[0], STDIN_FILENO);
 			close(pfd[0]);
 		}
 		close(pfd[1]);
 		execl(_PATH_PR, _PATH_PR, "-h", header, (char *)0);
 		_exit(127);
 	default:
 
 		/* parent */
 		if (pfd[1] != STDOUT_FILENO) {
 			pr->ostdout = dup(STDOUT_FILENO);
 			dup2(pfd[1], STDOUT_FILENO);
 			close(pfd[1]);
 			close(pfd[1]);
 			}
 			close(pfd[0]);
 			rewind(stdout);
 			free(header);
 			pr->kq = kqueue();
 			if (pr->kq == -1)
 				err(2, "kqueue");
 			pr->e = xmalloc(sizeof(struct kevent));
 			EV_SET(pr->e, pr_pd, EVFILT_PROCDESC, EV_ADD, NOTE_EXIT, 0,
 			    NULL);
 			if (kevent(pr->kq, pr->e, 1, NULL, 0, NULL) == -1)
 				err(2, "kevent");
 	}
 	return (pr);
 }
 
 /* close the pipe to pr and restore stdout */
 void
 stop_pr(struct pr *pr)
 {
 	int wstatus;
 
 	if (pr == NULL)
 		return;
 
 	fflush(stdout);
 	if (pr->ostdout != STDOUT_FILENO) {
 		close(STDOUT_FILENO);
 		dup2(pr->ostdout, STDOUT_FILENO);
 		close(pr->ostdout);
 	}
 	if (kevent(pr->kq, NULL, 0, pr->e, 1, NULL) == -1)
 		err(2, "kevent");
 	wstatus = pr->e[0].data;
 	close(pr->kq);
+	free(pr);
 	if (WIFEXITED(wstatus) && WEXITSTATUS(wstatus) != 0)
 		errx(2, "pr exited abnormally");
 	else if (WIFSIGNALED(wstatus))
 		errx(2, "pr killed by signal %d",
 		    WTERMSIG(wstatus));
 }