From b3295fd4e3d61a7ceabbad10a293db2dcd38b38b Mon Sep 17 00:00:00 2001
From: Simon Glass <sjg@chromium.org>
Date: Thu, 9 Jul 2020 18:39:42 -0600
Subject: [PATCH] binman: Allow zero-length entries to overlap

Some binary blobs unfortunately obtain their position in the image from
other binary blobs, such as Intel's 'descriptor'. In this case we cannot
rely on packing to work. It is not possible to produce a valid image in
any case, due to the missing blobs.

Allow zero-length overlaps so that this does not cause any problems.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
---
 tools/binman/etype/section.py               |  2 +-
 tools/binman/ftest.py                       |  4 ++++
 tools/binman/test/160_pack_overlap_zero.dts | 18 ++++++++++++++++++
 3 files changed, 23 insertions(+), 1 deletion(-)
 create mode 100644 tools/binman/test/160_pack_overlap_zero.dts

diff --git a/tools/binman/etype/section.py b/tools/binman/etype/section.py
index 7cd12c0204..73c5553c81 100644
--- a/tools/binman/etype/section.py
+++ b/tools/binman/etype/section.py
@@ -226,7 +226,7 @@ class Entry_section(Entry):
                             "at %#x (%d)" %
                             (entry.offset, entry.offset, self._skip_at_start,
                              self._skip_at_start))
-            if entry.offset < offset:
+            if entry.offset < offset and entry.size:
                 entry.Raise("Offset %#x (%d) overlaps with previous entry '%s' "
                             "ending at %#x (%d)" %
                             (entry.offset, entry.offset, prev_name, offset, offset))
diff --git a/tools/binman/ftest.py b/tools/binman/ftest.py
index 146d4c51d3..614ac4ed39 100644
--- a/tools/binman/ftest.py
+++ b/tools/binman/ftest.py
@@ -3421,6 +3421,10 @@ class TestFunctional(unittest.TestCase):
         err = stderr.getvalue()
         self.assertRegex(err, "Image 'main-section'.*missing.*: intel-ifwi")
 
+    def testPackOverlap(self):
+        """Test that zero-size overlapping regions are ignored"""
+        self._DoTestFile('160_pack_overlap_zero.dts')
+
 
 if __name__ == "__main__":
     unittest.main()
diff --git a/tools/binman/test/160_pack_overlap_zero.dts b/tools/binman/test/160_pack_overlap_zero.dts
new file mode 100644
index 0000000000..731aa1cbe6
--- /dev/null
+++ b/tools/binman/test/160_pack_overlap_zero.dts
@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+/dts-v1/;
+
+/ {
+	#address-cells = <1>;
+	#size-cells = <1>;
+
+	binman {
+		u-boot {
+		};
+
+		fill {
+			size = <0>;
+			offset = <3>;
+		};
+	};
+};