Index: sbin/fsck_ffs/fsck.h
===================================================================
--- sbin/fsck_ffs/fsck.h
+++ sbin/fsck_ffs/fsck.h
@@ -364,6 +364,7 @@
 #define	FOUND	0x10
 
 #define	EEXIT	8		/* Standard error exit. */
+#define	ERERUN	16		/* fsck needs to be re-run. */
 #define	ERESTART -1
 
 int flushentry(void);
Index: sbin/fsck_ffs/fsck_ffs.8
===================================================================
--- sbin/fsck_ffs/fsck_ffs.8
+++ sbin/fsck_ffs/fsck_ffs.8
@@ -29,7 +29,7 @@
 .\"	@(#)fsck.8	8.4 (Berkeley) 5/9/95
 .\" $FreeBSD$
 .\"
-.Dd February 14, 2017
+.Dd January 11, 2018
 .Dt FSCK_FFS 8
 .Os
 .Sh NAME
@@ -376,11 +376,41 @@
 .Sh EXIT STATUS
 .Ex -std
 .Pp
-If the option
+Specific non-zero exit status values used are:
+.Bl -tag -width indent
+.It 1
+Usage error (missing or invalid command arguments).
+.It 2
+The
+.Fl p
+option was used and a SIGQUIT was received, indicating that the system
+should be returned to single user mode after the file system check.
+.It 3
+The file system superblock cannot be read.
+This could indicate that the file system device does not exist or is not yet
+ready.
+.It 4
+A mounted file system was modified; the system should be rebooted.
+.It 5
+The
+.Fl B
+option was used and soft updates are not enabled on the file system.
+.It 6
+The
+.Fl B
+option was used and the kernel lacks needed support.
+.It 7
+The
 .Fl F
-is used,
+option was used and the file system is clean.
+.It 8
+General error exit.
+.It 16
+The file system could not be completely repaired.
+The file system may be able to be repaired by running
 .Nm
-exits 7 if the file system is clean.
+on the file system again.
+.El
 .Sh DIAGNOSTICS
 The diagnostics produced by
 .Nm
Index: sbin/fsck_ffs/main.c
===================================================================
--- sbin/fsck_ffs/main.c
+++ sbin/fsck_ffs/main.c
@@ -82,6 +82,7 @@
 	int ch;
 	struct rlimit rlimit;
 	struct itimerval itimerval;
+	int fsret;
 	int ret = 0;
 
 	sync();
@@ -196,8 +197,9 @@
 		(void)setrlimit(RLIMIT_DATA, &rlimit);
 	}
 	while (argc > 0) {
-		if (checkfilesys(*argv) == ERESTART)
+		if ((fsret = checkfilesys(*argv)) == ERESTART)
 			continue;
+		ret |= fsret;
 		argc--;
 		argv++;
 	}
@@ -585,7 +587,7 @@
 		sync();
 		return (4);
 	}
-	return (0);
+	return (rerun ? ERERUN : 0);
 }
 
 static int