diff --git a/ChangeLog b/ChangeLog
index 17d0e243e..8dfaf47d4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2013-12-18  Vladimir Serbinenko  <phcoder@gmail.com>
+
+	Make grub_zlib_decompress handle incomplete chunks.
+
+	Fixes squash4.
+
 2013-12-18  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	* grub-core/Makefile.am: Don't attempt to export grub_bios_interrupt
diff --git a/grub-core/fs/btrfs.c b/grub-core/fs/btrfs.c
index b15a9d65d..89666b6fd 100644
--- a/grub-core/fs/btrfs.c
+++ b/grub-core/fs/btrfs.c
@@ -1104,7 +1104,12 @@ grub_btrfs_extent_read (struct grub_btrfs_data *data,
 					 - (grub_uint8_t *) data->extent),
 					extoff, buf, csize)
 		  != (grub_ssize_t) csize)
-		return -1;
+		{
+		  if (!grub_errno)
+		    grub_error (GRUB_ERR_BAD_COMPRESSED_DATA,
+				"premature end of compressed");
+		  return -1;
+		}
 	    }
 	  else if (data->extent->compression == GRUB_BTRFS_COMPRESSION_LZO)
 	    {
@@ -1158,7 +1163,12 @@ grub_btrfs_extent_read (struct grub_btrfs_data *data,
 	      grub_free (tmp);
 
 	      if (ret != (grub_ssize_t) csize)
-		return -1;
+		{
+		  if (!grub_errno)
+		    grub_error (GRUB_ERR_BAD_COMPRESSED_DATA,
+				"premature end of compressed");
+		  return -1;
+		}
 
 	      break;
 	    }
diff --git a/grub-core/fs/hfspluscomp.c b/grub-core/fs/hfspluscomp.c
index 461b4678f..d76f3f137 100644
--- a/grub-core/fs/hfspluscomp.c
+++ b/grub-core/fs/hfspluscomp.c
@@ -156,8 +156,12 @@ hfsplus_read_compressed_real (struct grub_hfsplus_file *node,
 	  if (ts > node->size - (pos & ~(HFSPLUS_COMPRESS_BLOCK_SIZE)))
 	    ts = node->size - (pos & ~(HFSPLUS_COMPRESS_BLOCK_SIZE));
 	  if (grub_zlib_decompress (tmp_buf, sz, 0,
-				    node->cbuf, ts) < 0)
+				    node->cbuf, ts) != (grub_ssize_t) ts)
 	    {
+	      if (!grub_errno)
+		grub_error (GRUB_ERR_BAD_COMPRESSED_DATA,
+			    "premature end of compressed");
+
 	      grub_free (tmp_buf);
 	      return -1;
 	    }
@@ -288,8 +292,14 @@ hfsplus_open_compressed_real (struct grub_hfsplus_file *node)
   if (grub_zlib_decompress ((char *) (cmp_head + 1),
 			    grub_cpu_to_be64 (attr_head->size)
 			    - sizeof (*cmp_head), 0,
-			    node->cbuf, node->size) < 0)
-    return grub_errno;
+			    node->cbuf, node->size)
+      != (grub_ssize_t) node->size)
+    {
+      if (!grub_errno)
+	grub_error (GRUB_ERR_BAD_COMPRESSED_DATA,
+		    "premature end of compressed");
+      return grub_errno;
+    }
   node->compressed = 1;
   return 0;
 }
diff --git a/grub-core/fs/zfs/zfs.c b/grub-core/fs/zfs/zfs.c
index 4d0bde4ce..cfb25c030 100644
--- a/grub-core/fs/zfs/zfs.c
+++ b/grub-core/fs/zfs/zfs.c
@@ -293,9 +293,13 @@ static grub_err_t
 zlib_decompress (void *s, void *d,
 		 grub_size_t slen, grub_size_t dlen)
 {
-  if (grub_zlib_decompress (s, slen, 0, d, dlen) < 0)
-    return grub_errno;
-  return GRUB_ERR_NONE;
+  if (grub_zlib_decompress (s, slen, 0, d, dlen) == (grub_ssize_t) dlen)
+    return GRUB_ERR_NONE;
+
+  if (!grub_errno)
+    grub_error (GRUB_ERR_BAD_COMPRESSED_DATA,
+		"premature end of compressed");
+  return grub_errno;
 }
 
 static grub_err_t 
diff --git a/grub-core/io/gzio.c b/grub-core/io/gzio.c
index aec798f59..129209e37 100644
--- a/grub-core/io/gzio.c
+++ b/grub-core/io/gzio.c
@@ -1303,12 +1303,6 @@ grub_zlib_decompress (char *inbuf, grub_size_t insize, grub_off_t off,
   ret = grub_gzio_read_real (gzio, off, outbuf, outsize);
   grub_free (gzio);
 
-  if (!grub_errno && ret != (grub_ssize_t) outsize)
-    {
-      grub_error (GRUB_ERR_BAD_COMPRESSED_DATA, "premature end of compressed");
-      ret = -1;
-    }
-
   /* FIXME: Check Adler.  */
   return ret;
 }