diff --git a/sbin/fsck_ffs/fsck.h b/sbin/fsck_ffs/fsck.h
--- a/sbin/fsck_ffs/fsck.h
+++ b/sbin/fsck_ffs/fsck.h
@@ -67,6 +67,7 @@
 #include <unistd.h>
 #include <stdlib.h>
 #include <stdio.h>
+#include <libufs.h>
 
 #include <sys/queue.h>
 
@@ -425,6 +426,20 @@
 			break;
 	return (retval);
 }
+/*
+ * Allocate a block of memory to be used as an I/O buffer.
+ * Ensure that the buffer is aligned to the I/O subsystem requirements.
+ */
+static inline void*
+Balloc(size_t size)
+{
+	void *retval;
+
+	while ((retval = aligned_alloc(LIBUFS_BUFALIGN, size)) == NULL)
+		if (flushentry() == 0)
+			break;
+	return (retval);
+}
 
 /*
  * Wrapper for calloc() that flushes the cylinder group cache to try 
diff --git a/sbin/fsck_ffs/fsutil.c b/sbin/fsck_ffs/fsutil.c
--- a/sbin/fsck_ffs/fsutil.c
+++ b/sbin/fsck_ffs/fsutil.c
@@ -58,7 +58,6 @@
 #include <stdlib.h>
 #include <time.h>
 #include <unistd.h>
-#include <libufs.h>
 
 #include "fsck.h"
 
@@ -189,7 +188,7 @@
 	initbarea(&failedbuf, BT_UNKNOWN);
 	failedbuf.b_errs = -1;
 	failedbuf.b_un.b_buf = NULL;
-	if ((cgblk.b_un.b_buf = Malloc((unsigned int)sblock.fs_bsize)) == NULL)
+	if ((cgblk.b_un.b_buf = Balloc((unsigned int)sblock.fs_bsize)) == NULL)
 		errx(EEXIT, "Initial malloc(%d) failed", sblock.fs_bsize);
 	initbarea(&cgblk, BT_CYLGRP);
 	numbufs = cachelookups = cachereads = 0;
@@ -211,7 +210,7 @@
 	char *bufp;
 
 	bp = (struct bufarea *)Malloc(sizeof(struct bufarea));
-	bufp = Malloc((unsigned int)sblock.fs_bsize);
+	bufp = Balloc((unsigned int)sblock.fs_bsize);
 	if (bp == NULL || bufp == NULL) {
 		errx(EEXIT, "%s", failreason);
 		/* NOTREACHED */
@@ -241,7 +240,7 @@
 	if ((unsigned) cg >= sblock.fs_ncg)
 		errx(EEXIT, "cglookup: out of range cylinder group %d", cg);
 	if (cgbufs == NULL) {
-		cgbufs = calloc(sblock.fs_ncg, sizeof(struct bufarea));
+		cgbufs = Calloc(sblock.fs_ncg, sizeof(struct bufarea));
 		if (cgbufs == NULL)
 			errx(EEXIT, "Cannot allocate cylinder group buffers");
 	}
@@ -250,7 +249,7 @@
 		return (cgbp);
 	cgp = NULL;
 	if (flushtries == 0)
-		cgp = Malloc((unsigned int)sblock.fs_cgsize);
+		cgp = Balloc((unsigned int)sblock.fs_cgsize);
 	if (cgp == NULL) {
 		if (sujrecovery)
 			errx(EEXIT,"Ran out of memory during journal recovery");
@@ -967,7 +966,7 @@
 	if (fd < 0)
 		return;
 	if (zero == NULL) {
-		zero = calloc(ZEROBUFSIZE, 1);
+		zero = Balloc(ZEROBUFSIZE);
 		if (zero == NULL)
 			errx(EEXIT, "cannot allocate buffer pool");
 	}
diff --git a/sbin/fsck_ffs/inode.c b/sbin/fsck_ffs/inode.c
--- a/sbin/fsck_ffs/inode.c
+++ b/sbin/fsck_ffs/inode.c
@@ -48,7 +48,6 @@
 #include <pwd.h>
 #include <string.h>
 #include <time.h>
-#include <libufs.h>
 
 #include "fsck.h"
 
@@ -646,7 +645,7 @@
 		inobufsize = blkroundup(&sblock,
 		    MAX(INOBUFSIZE, sblock.fs_bsize));
 		initbarea(&inobuf, BT_INODES);
-		if ((inobuf.b_un.b_buf = Malloc((unsigned)inobufsize)) == NULL)
+		if ((inobuf.b_un.b_buf = Balloc((unsigned)inobufsize)) == NULL)
 			errx(EEXIT, "cannot allocate space for inode buffer");
 	}
 	fullcnt = inobufsize / ((sblock.fs_magic == FS_UFS1_MAGIC) ?
diff --git a/sbin/fsck_ffs/main.c b/sbin/fsck_ffs/main.c
--- a/sbin/fsck_ffs/main.c
+++ b/sbin/fsck_ffs/main.c
@@ -59,7 +59,6 @@
 #include <fstab.h>
 #include <grp.h>
 #include <inttypes.h>
-#include <libufs.h>
 #include <mntopts.h>
 #include <paths.h>
 #include <stdint.h>
diff --git a/sbin/fsck_ffs/pass5.c b/sbin/fsck_ffs/pass5.c
--- a/sbin/fsck_ffs/pass5.c
+++ b/sbin/fsck_ffs/pass5.c
@@ -45,7 +45,6 @@
 #include <inttypes.h>
 #include <limits.h>
 #include <string.h>
-#include <libufs.h>
 
 #include "fsck.h"
 
diff --git a/sbin/fsck_ffs/setup.c b/sbin/fsck_ffs/setup.c
--- a/sbin/fsck_ffs/setup.c
+++ b/sbin/fsck_ffs/setup.c
@@ -52,7 +52,6 @@
 #include <limits.h>
 #include <stdint.h>
 #include <string.h>
-#include <libufs.h>
 
 #include "fsck.h"
 
@@ -214,7 +213,7 @@
 		sbdirty();
 	}
 	if (snapcnt > 0 && copybuf == NULL) {
-		copybuf = Malloc(sblock.fs_bsize);
+		copybuf = Balloc(sblock.fs_bsize);
 		if (copybuf == NULL)
 			errx(EEXIT, "cannot allocate space for snapshot "
 			    "copy buffer");
@@ -499,7 +498,7 @@
 	fsmodified = 0;
 	lfdir = 0;
 	initbarea(&sblk, BT_SUPERBLK);
-	sblk.b_un.b_buf = Malloc(SBLOCKSIZE);
+	sblk.b_un.b_buf = Balloc(SBLOCKSIZE);
 	if (sblk.b_un.b_buf == NULL)
 		errx(EEXIT, "cannot allocate space for superblock");
 	dev_bsize = secsize = DEV_BSIZE;
@@ -528,7 +527,7 @@
 	 */
 	if (ioctl(devfd, DIOCGSECTORSIZE, &secsize) == -1)
 		return (0);
-	fsrbuf = Malloc(secsize);
+	fsrbuf = Balloc(secsize);
 	if (fsrbuf == NULL)
 		errx(EEXIT, "calcsb: cannot allocate recovery buffer");
 	if (blread(devfd, fsrbuf,
@@ -571,7 +570,7 @@
 	rdsize = sblock.fs_fsize;
 	if (ioctl(devfd, DIOCGSECTORSIZE, &secsize) == -1 ||
 	    rdsize % secsize != 0 ||
-	    (fsrbuf = Malloc(rdsize)) == NULL ||
+	    (fsrbuf = Balloc(rdsize)) == NULL ||
 	    blread(devfd, fsrbuf, (SBLOCK_UFS2 - rdsize) / dev_bsize,
 	      rdsize) != 0) {
 		free(fsrbuf);
@@ -610,7 +609,7 @@
 	if (sblock.fs_magic != FS_UFS2_MAGIC ||
 	    ioctl(readfd, DIOCGSECTORSIZE, &secsize) == -1 ||
 	    rdsize % secsize != 0 ||
-	    (fsrbuf = Malloc(rdsize)) == NULL ||
+	    (fsrbuf = Balloc(rdsize)) == NULL ||
 	    blread(readfd, fsrbuf, (SBLOCK_UFS2 - rdsize) / dev_bsize,
 	      rdsize) != 0) {
 		printf("RECOVERY DATA COULD NOT BE CREATED\n");
diff --git a/sbin/fsck_ffs/suj.c b/sbin/fsck_ffs/suj.c
--- a/sbin/fsck_ffs/suj.c
+++ b/sbin/fsck_ffs/suj.c
@@ -47,7 +47,6 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdint.h>
-#include <libufs.h>
 #include <string.h>
 #include <strings.h>
 #include <sysexits.h>
@@ -2274,7 +2273,7 @@
 static void
 suj_read(void)
 {
-	uint8_t block[1 * 1024 * 1024];
+	uint8_t block[1 * 1024 * 1024] __aligned(LIBUFS_BUFALIGN);
 	struct suj_seg *seg;
 	struct jsegrec *recn;
 	struct jsegrec *rec;