diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c
index 162711cc5b20..ce38505a823c 100644
--- a/fs/ocfs2/alloc.c
+++ b/fs/ocfs2/alloc.c
@@ -6164,7 +6164,7 @@ static int ocfs2_get_truncate_log_info(struct ocfs2_super *osb,
 	struct buffer_head *bh = NULL;
 	struct ocfs2_dinode *di;
 	struct ocfs2_truncate_log *tl;
-	unsigned int tl_count;
+	unsigned int tl_count, tl_used;
 
 	inode = ocfs2_get_system_file_inode(osb,
 					   TRUNCATE_LOG_SYSTEM_INODE,
@@ -6184,9 +6184,10 @@ static int ocfs2_get_truncate_log_info(struct ocfs2_super *osb,
 
 	di = (struct ocfs2_dinode *)bh->b_data;
 	tl = &di->id2.i_dealloc;
+	tl_used = le16_to_cpu(tl->tl_used);
 	tl_count = le16_to_cpu(tl->tl_count);
 	if (unlikely(tl_count > ocfs2_truncate_recs_per_inode(osb->sb) ||
-		     tl_count == 0)) {
+		     tl_count == 0 || tl_used > tl_count)) {
 		status = -EFSCORRUPTED;
 		iput(inode);
 		brelse(bh);
diff --git a/fs/ocfs2/dir.c b/fs/ocfs2/dir.c
index 8c9c4825f984..2785ff245e79 100644
--- a/fs/ocfs2/dir.c
+++ b/fs/ocfs2/dir.c
@@ -302,8 +302,21 @@ static int ocfs2_check_dir_entry(struct inode *dir,
 				 unsigned long offset)
 {
 	const char *error_msg = NULL;
-	const int rlen = le16_to_cpu(de->rec_len);
-	const unsigned long next_offset = ((char *) de - buf) + rlen;
+	unsigned long next_offset;
+	int rlen;
+
+	if (offset > size - OCFS2_DIR_REC_LEN(1)) {
+		/* Dirent is (maybe partially) beyond the buffer
+		 * boundaries so touching 'de' members is unsafe.
+		 */
+		mlog(ML_ERROR, "directory entry (#%llu: offset=%lu) "
+		     "too close to end or out-of-bounds",
+		     (unsigned long long)OCFS2_I(dir)->ip_blkno, offset);
+		return 0;
+	}
+
+	rlen = le16_to_cpu(de->rec_len);
+	next_offset = ((char *) de - buf) + rlen;
 
 	if (unlikely(rlen < OCFS2_DIR_REC_LEN(1)))
 		error_msg = "rec_len is smaller than minimal";
@@ -778,6 +791,14 @@ static int ocfs2_dx_dir_lookup_rec(struct inode *inode,
 	struct ocfs2_extent_block *eb;
 	struct ocfs2_extent_rec *rec = NULL;
 
+	if (le16_to_cpu(el->l_count) !=
+	    ocfs2_extent_recs_per_dx_root(inode->i_sb)) {
+		ret = ocfs2_error(inode->i_sb,
+				  "Inode %lu has invalid extent list length %u\n",
+				  inode->i_ino, le16_to_cpu(el->l_count));
+		goto out;
+	}
+
 	if (el->l_tree_depth) {
 		ret = ocfs2_find_leaf(INODE_CACHE(inode), el, major_hash,
 				      &eb_bh);
@@ -3423,6 +3444,14 @@ static int ocfs2_find_dir_space_id(struct inode *dir, struct buffer_head *di_bh,
 		offset += le16_to_cpu(de->rec_len);
 	}
 
+	if (!last_de) {
+		ret = ocfs2_error(sb, "Directory entry (#%llu: size=%lld) "
+				  "is unexpectedly short",
+				  (unsigned long long)OCFS2_I(dir)->ip_blkno,
+				  i_size_read(dir));
+		goto out;
+	}
+
 	/*
 	 * We're going to require expansion of the directory - figure
 	 * out how many blocks we'll need so that a place for the
@@ -4104,10 +4133,15 @@ static int ocfs2_expand_inline_dx_root(struct inode *dir,
 	}
 
 	dx_root->dr_flags &= ~OCFS2_DX_FLAG_INLINE;
-	memset(&dx_root->dr_list, 0, osb->sb->s_blocksize -
-	       offsetof(struct ocfs2_dx_root_block, dr_list));
+
+	dx_root->dr_list.l_tree_depth = 0;
 	dx_root->dr_list.l_count =
 		cpu_to_le16(ocfs2_extent_recs_per_dx_root(osb->sb));
+	dx_root->dr_list.l_next_free_rec = 0;
+	memset(&dx_root->dr_list.l_recs, 0,
+	       osb->sb->s_blocksize -
+	       (offsetof(struct ocfs2_dx_root_block, dr_list) +
+		offsetof(struct ocfs2_extent_list, l_recs)));
 
 	/* This should never fail considering we start with an empty
 	 * dx_root. */
diff --git a/fs/ocfs2/localalloc.c b/fs/ocfs2/localalloc.c
index d1aa04a5af1b..56be21c695d6 100644
--- a/fs/ocfs2/localalloc.c
+++ b/fs/ocfs2/localalloc.c
@@ -905,13 +905,11 @@ static int ocfs2_local_alloc_find_clear_bits(struct ocfs2_super *osb,
 static void ocfs2_clear_local_alloc(struct ocfs2_dinode *alloc)
 {
 	struct ocfs2_local_alloc *la = OCFS2_LOCAL_ALLOC(alloc);
-	int i;
 
 	alloc->id1.bitmap1.i_total = 0;
 	alloc->id1.bitmap1.i_used = 0;
 	la->la_bm_off = 0;
-	for(i = 0; i < le16_to_cpu(la->la_size); i++)
-		la->la_bitmap[i] = 0;
+	memset(la->la_bitmap, 0, le16_to_cpu(la->la_size));
 }
 
 #if 0
diff --git a/fs/ocfs2/move_extents.c b/fs/ocfs2/move_extents.c
index 86f2631e6360..ba4952b41602 100644
--- a/fs/ocfs2/move_extents.c
+++ b/fs/ocfs2/move_extents.c
@@ -98,7 +98,13 @@ static int __ocfs2_move_extent(handle_t *handle,
 
 	rec = &el->l_recs[index];
 
-	BUG_ON(ext_flags != rec->e_flags);
+	if (ext_flags != rec->e_flags) {
+		ret = ocfs2_error(inode->i_sb,
+				  "Inode %llu has corrupted extent %d with flags 0x%x at cpos %u\n",
+				  (unsigned long long)ino, index, rec->e_flags, cpos);
+		goto out;
+	}
+
 	/*
 	 * after moving/defraging to new location, the extent is not going
 	 * to be refcounted anymore.
@@ -1031,6 +1037,12 @@ int ocfs2_ioctl_move_extents(struct file *filp, void __user *argp)
 	if (range.me_threshold > i_size_read(inode))
 		range.me_threshold = i_size_read(inode);
 
+	if (range.me_flags & ~(OCFS2_MOVE_EXT_FL_AUTO_DEFRAG |
+			       OCFS2_MOVE_EXT_FL_PART_DEFRAG)) {
+		status = -EINVAL;
+		goto out_free;
+	}
+
 	if (range.me_flags & OCFS2_MOVE_EXT_FL_AUTO_DEFRAG) {
 		context->auto_defrag = 1;
 
diff --git a/fs/ocfs2/ocfs2_fs.h b/fs/ocfs2/ocfs2_fs.h
index ae0e44e5f2ad..c501eb3cdcda 100644
--- a/fs/ocfs2/ocfs2_fs.h
+++ b/fs/ocfs2/ocfs2_fs.h
@@ -468,7 +468,8 @@ struct ocfs2_extent_list {
 	__le16 l_reserved1;
 	__le64 l_reserved2;		/* Pad to
 					   sizeof(ocfs2_extent_rec) */
-/*10*/	struct ocfs2_extent_rec l_recs[];	/* Extent records */
+					/* Extent records */
+/*10*/	struct ocfs2_extent_rec l_recs[] __counted_by_le(l_count);
 };
 
 /*
@@ -482,7 +483,8 @@ struct ocfs2_chain_list {
 	__le16 cl_count;		/* Total chains in this list */
 	__le16 cl_next_free_rec;	/* Next unused chain slot */
 	__le64 cl_reserved1;
-/*10*/	struct ocfs2_chain_rec cl_recs[];	/* Chain records */
+					/* Chain records */
+/*10*/	struct ocfs2_chain_rec cl_recs[] __counted_by_le(cl_count);
 };
 
 /*
@@ -494,7 +496,8 @@ struct ocfs2_truncate_log {
 /*00*/	__le16 tl_count;		/* Total records in this log */
 	__le16 tl_used;			/* Number of records in use */
 	__le32 tl_reserved1;
-/*08*/	struct ocfs2_truncate_rec tl_recs[];	/* Truncate records */
+					/* Truncate records */
+/*08*/	struct ocfs2_truncate_rec tl_recs[] __counted_by_le(tl_count);
 };
 
 /*
@@ -638,7 +641,7 @@ struct ocfs2_local_alloc
 	__le16 la_size;		/* Size of included bitmap, in bytes */
 	__le16 la_reserved1;
 	__le64 la_reserved2;
-/*10*/	__u8   la_bitmap[];
+/*10*/	__u8   la_bitmap[] __counted_by_le(la_size);
 };
 
 /*
@@ -651,7 +654,7 @@ struct ocfs2_inline_data
 				 * for data, starting at id_data */
 	__le16	id_reserved0;
 	__le32	id_reserved1;
-	__u8	id_data[];	/* Start of user data */
+	__u8	id_data[] __counted_by_le(id_count);	/* Start of user data */
 };
 
 /*
@@ -796,9 +799,10 @@ struct ocfs2_dx_entry_list {
 					 * possible in de_entries */
 	__le16		de_num_used;	/* Current number of
 					 * de_entries entries */
-	struct	ocfs2_dx_entry		de_entries[];	/* Indexed dir entries
-							 * in a packed array of
-							 * length de_num_used */
+					/* Indexed dir entries in a packed
+					 * array of length de_num_used.
+					 */
+	struct	ocfs2_dx_entry		de_entries[] __counted_by_le(de_count);
 };
 
 #define OCFS2_DX_FLAG_INLINE	0x01
@@ -934,7 +938,8 @@ struct ocfs2_refcount_list {
 	__le16 rl_used;		/* Current number of used records */
 	__le32 rl_reserved2;
 	__le64 rl_reserved1;	/* Pad to sizeof(ocfs2_refcount_record) */
-/*10*/	struct ocfs2_refcount_rec rl_recs[];	/* Refcount records */
+				/* Refcount records */
+/*10*/	struct ocfs2_refcount_rec rl_recs[] __counted_by_le(rl_count);
 };
 
 
@@ -1020,7 +1025,8 @@ struct ocfs2_xattr_header {
 						    buckets.  A block uses
 						    xb_check and sets
 						    this field to zero.) */
-	struct ocfs2_xattr_entry xh_entries[]; /* xattr entry list. */
+						/* xattr entry list. */
+	struct ocfs2_xattr_entry xh_entries[] __counted_by_le(xh_count);
 };
 
 /*
diff --git a/fs/ocfs2/suballoc.c b/fs/ocfs2/suballoc.c
index 6ac4dcd54588..9969a041ab18 100644
--- a/fs/ocfs2/suballoc.c
+++ b/fs/ocfs2/suballoc.c
@@ -649,6 +649,16 @@ ocfs2_block_group_alloc_discontig(handle_t *handle,
 	return status ? ERR_PTR(status) : bg_bh;
 }
 
+static int ocfs2_check_chain_list(struct ocfs2_chain_list *cl,
+				  struct super_block *sb)
+{
+	if (le16_to_cpu(cl->cl_count) != ocfs2_chain_recs_per_inode(sb))
+		return -EINVAL;
+	if (le16_to_cpu(cl->cl_next_free_rec) > le16_to_cpu(cl->cl_count))
+		return -EINVAL;
+	return 0;
+}
+
 /*
  * We expect the block group allocator to already be locked.
  */
@@ -671,6 +681,10 @@ static int ocfs2_block_group_alloc(struct ocfs2_super *osb,
 	BUG_ON(ocfs2_is_cluster_bitmap(alloc_inode));
 
 	cl = &fe->id2.i_chain;
+	status = ocfs2_check_chain_list(cl, alloc_inode->i_sb);
+	if (status)
+		goto bail;
+
 	status = ocfs2_reserve_clusters_with_limit(osb,
 						   le16_to_cpu(cl->cl_cpg),
 						   max_block, flags, &ac);
@@ -1992,6 +2006,9 @@ static int ocfs2_claim_suballoc_bits(struct ocfs2_alloc_context *ac,
 	}
 
 	cl = (struct ocfs2_chain_list *) &fe->id2.i_chain;
+	status = ocfs2_check_chain_list(cl, ac->ac_inode->i_sb);
+	if (status)
+		goto bail;
 
 	victim = ocfs2_find_victim_chain(cl);
 	ac->ac_chain = victim;