diff --git a/sbin/fsck_ffs/SMM.doc/3.t b/sbin/fsck_ffs/SMM.doc/3.t
index 1cacb506b5d8..84372c581dd4 100644
--- a/sbin/fsck_ffs/SMM.doc/3.t
+++ b/sbin/fsck_ffs/SMM.doc/3.t
@@ -1,4 +1,4 @@
-.\"	$NetBSD: 3.t,v 1.3 1996/04/05 01:45:45 cgd Exp $
+.\"	$NetBSD: 3.t,v 1.4 1996/10/11 20:15:49 thorpej Exp $
 .\"
 .\" Copyright (c) 1982, 1993
 .\"	The Regents of the University of California.  All rights reserved.
@@ -346,6 +346,19 @@ will remove that directory entry.
 Again,
 this condition can only arise when there has been a hardware failure.
 .PP
+.I Fsck
+also checks for directories with unallocated blocks (holes).
+Such directories should never be created.
+When found,
+.I fsck
+will prompt the user to adjust the length of the offending directory
+which is done by shortening the size of the directory to the end of the
+last allocated block preceeding the hole.
+Unfortunately, this means that another Phase 1 run has to be done. 
+.I Fsck
+will remind the user to rerun fsck after repairing a
+directory containing an unallocated block.
+.PP
 If a directory entry inode number references
 outside the inode list, then
 .I fsck_ffs
diff --git a/sbin/fsck_ffs/fsck.h b/sbin/fsck_ffs/fsck.h
index 36ed6b1aac3a..84af0bfb29aa 100644
--- a/sbin/fsck_ffs/fsck.h
+++ b/sbin/fsck_ffs/fsck.h
@@ -1,4 +1,4 @@
-/*	$NetBSD: fsck.h,v 1.12 1996/09/23 16:18:33 christos Exp $	*/
+/*	$NetBSD: fsck.h,v 1.13 1996/10/11 20:15:46 thorpej Exp $	*/
 
 /*
  * Copyright (c) 1980, 1986, 1993
@@ -181,6 +181,7 @@ char	skipclean;		/* skip clean file systems if preening */
 int	fsmodified;		/* 1 => write done to file system */
 int	fsreadfd;		/* file descriptor for reading file system */
 int	fswritefd;		/* file descriptor for writing file system */
+int	rerun;			/* rerun fsck.  Only used in non-preen mode */
 
 daddr_t	maxfsblock;		/* number of blocks in the file system */
 char	*blockmap;		/* ptr to primary blk allocation map */
diff --git a/sbin/fsck_ffs/inode.c b/sbin/fsck_ffs/inode.c
index ca936079fab6..75876d23b84e 100644
--- a/sbin/fsck_ffs/inode.c
+++ b/sbin/fsck_ffs/inode.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: inode.c,v 1.22 1996/09/27 22:45:13 christos Exp $	*/
+/*	$NetBSD: inode.c,v 1.23 1996/10/11 20:15:47 thorpej Exp $	*/
 
 /*
  * Copyright (c) 1980, 1986, 1993
@@ -37,7 +37,7 @@
 #if 0
 static char sccsid[] = "@(#)inode.c	8.5 (Berkeley) 2/8/95";
 #else
-static char rcsid[] = "$NetBSD: inode.c,v 1.22 1996/09/27 22:45:13 christos Exp $";
+static char rcsid[] = "$NetBSD: inode.c,v 1.23 1996/10/11 20:15:47 thorpej Exp $";
 #endif
 #endif /* not lint */
 
@@ -71,6 +71,7 @@ ckinode(dp, idesc)
 	struct dinode dino;
 	u_int64_t remsize, sizepb;
 	mode_t mode;
+	char pathbuf[MAXPATHLEN + 1];
 
 	if (idesc->id_fix != IGNORE)
 		idesc->id_fix = DONTKNOW;
@@ -89,8 +90,25 @@ ckinode(dp, idesc)
 				numfrags(&sblock, fragroundup(&sblock, offset));
 		else
 			idesc->id_numfrags = sblock.fs_frag;
-		if (*ap == 0)
+		if (*ap == 0) {
+			if (idesc->id_type == DATA && ndb >= 0) {
+				/* An empty block in a directory XXX */
+				getpathname(pathbuf, idesc->id_number,
+				    idesc->id_number);
+				pfatal("DIRECTORY %s: CONTAINS EMPTY BLOCKS",
+				    pathbuf);
+				if (reply("ADJUST LENGTH") == 1) {
+					dp = ginode(idesc->id_number);
+					dp->di_size = (ap - &dino.di_db[0]) *
+					    sblock.fs_bsize;
+					printf(
+					    "YOU MUST RERUN FSCK AFTERWARDS\n");
+					rerun = 1;
+					inodirty();
+				}
+			}
 			continue;
+		}
 		idesc->id_blkno = *ap;
 		if (idesc->id_type == ADDR)
 			ret = (*idesc->id_func)(idesc);
@@ -108,6 +126,24 @@ ckinode(dp, idesc)
 			ret = iblock(idesc, n, remsize);
 			if (ret & STOP)
 				return (ret);
+		} else {
+			if (idesc->id_type == DATA && remsize > 0) {
+				/* An empty block in a directory XXX */
+				getpathname(pathbuf, idesc->id_number,
+				    idesc->id_number);
+				pfatal("DIRECTORY %s: CONTAINS EMPTY BLOCKS",
+				    pathbuf);
+				if (reply("ADJUST LENGTH") == 1) {
+					dp = ginode(idesc->id_number);
+					dp->di_size -= remsize;
+					remsize = 0;
+					printf(
+					    "YOU MUST RERUN FSCK AFTERWARDS\n");
+					rerun = 1;
+					inodirty();
+					break;
+				}
+			}
 		}
 		sizepb *= NINDIR(&sblock);
 		remsize -= sizepb;
@@ -127,6 +163,8 @@ iblock(idesc, ilevel, isize)
 	int i, n, (*func) __P((struct inodesc *)), nif;
 	u_int64_t sizepb;
 	char buf[BUFSIZ];
+	char pathbuf[MAXPATHLEN + 1];
+	struct dinode *dp;
 
 	if (idesc->id_type == ADDR) {
 		func = idesc->id_func;
@@ -170,6 +208,25 @@ iblock(idesc, ilevel, isize)
 				bp->b_flags &= ~B_INUSE;
 				return (n);
 			}
+		} else {
+			if (idesc->id_type == DATA && isize > 0) {
+				/* An empty block in a directory XXX */
+				getpathname(pathbuf, idesc->id_number,
+				    idesc->id_number);
+				pfatal("DIRECTORY %s: CONTAINS EMPTY BLOCKS",
+				    pathbuf);
+				if (reply("ADJUST LENGTH") == 1) {
+					dp = ginode(idesc->id_number);
+					dp->di_size -= isize;
+					isize = 0;
+					printf(
+					    "YOU MUST RERUN FSCK AFTERWARDS\n");
+					rerun = 1;
+					inodirty();
+					bp->b_flags &= ~B_INUSE;
+					return(STOP);
+				}
+			}
 		}
 		isize -= sizepb;
 	}
diff --git a/sbin/fsck_ffs/main.c b/sbin/fsck_ffs/main.c
index 3af2077720cf..f9d5a6928bbb 100644
--- a/sbin/fsck_ffs/main.c
+++ b/sbin/fsck_ffs/main.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: main.c,v 1.21 1996/09/27 22:45:14 christos Exp $	*/
+/*	$NetBSD: main.c,v 1.22 1996/10/11 20:15:48 thorpej Exp $	*/
 
 /*
  * Copyright (c) 1980, 1986, 1993
@@ -43,7 +43,7 @@ static char copyright[] =
 #if 0
 static char sccsid[] = "@(#)main.c	8.2 (Berkeley) 1/23/94";
 #else
-static char rcsid[] = "$NetBSD: main.c,v 1.21 1996/09/27 22:45:14 christos Exp $";
+static char rcsid[] = "$NetBSD: main.c,v 1.22 1996/10/11 20:15:48 thorpej Exp $";
 #endif
 #endif /* not lint */
 
@@ -311,6 +311,8 @@ checkfilesys(filesys, mntpt, auxdata, child)
 		return (0);
 	if (!preen)
 		printf("\n***** FILE SYSTEM WAS MODIFIED *****\n");
+	if (rerun)
+		printf("\n***** PLEASE RERUN FSCK *****\n");
 	if (hotroot()) {
 		struct statfs stfs_buf;
 		/*