diff --git a/sha1_file.c b/sha1_file.c
index 4cc8939e4..63981fb3f 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -1357,8 +1357,6 @@ unsigned long get_size_from_delta(struct packed_git *p,
 		in = use_pack(p, w_curs, curpos, &stream.avail_in);
 		stream.next_in = in;
 		st = git_inflate(&stream, Z_FINISH);
-		if (st == Z_BUF_ERROR && (stream.avail_in || !stream.avail_out))
-			break;
 		curpos += stream.next_in - in;
 	} while ((st == Z_OK || st == Z_BUF_ERROR) &&
 		 stream.total_out < sizeof(delta_head));
@@ -1589,15 +1587,15 @@ static void *unpack_compressed_entry(struct packed_git *p,
 	buffer[size] = 0;
 	memset(&stream, 0, sizeof(stream));
 	stream.next_out = buffer;
-	stream.avail_out = size;
+	stream.avail_out = size + 1;
 
 	git_inflate_init(&stream);
 	do {
 		in = use_pack(p, w_curs, curpos, &stream.avail_in);
 		stream.next_in = in;
 		st = git_inflate(&stream, Z_FINISH);
-		if (st == Z_BUF_ERROR && (stream.avail_in || !stream.avail_out))
-			break;
+		if (!stream.avail_out)
+			break; /* the payload is larger than it should be */
 		curpos += stream.next_in - in;
 	} while (st == Z_OK || st == Z_BUF_ERROR);
 	git_inflate_end(&stream);