fit_import_data() in tools/fit_image.c declares the data pointer and the name of the external data property outside its loop over the /images subnodes, so both values leak from one image into the next. An image node that carries data-size but neither data-offset nor data-position then reuses the pointer left behind by the previously imported image: the previous image's data is written into the node, after which the import aborts trying to delete an external data property the node never had. Since that abort path only prints a debug() message, a regular mkimage build fails with nothing but the generic usage text. The failure mode also depends on the order of the image nodes: when no externally stored image precedes the malformed node, the pointer is still NULL, the node is skipped, and the hashing stage reports a proper error instead.
A FIT authored from a .its cannot hit this, because dtc-authored images carry inline data. It takes re-processing an external-data FIT in which an image has lost its data-offset, for example one edited with fdtput -d or produced by another tool: mkimage -E -f demo.its demo.itb fdtput -d demo.itb /images/kernel-2 data-offset mkimage -F demo.itb There is no silent-success path, because the failing property delete always aborts the run before the file is written back, but the user is left without any indication of what is wrong. Patch 1 moves the declarations into the loop so that each image starts from a clean state. A node without an external data reference is now skipped consistently regardless of node order, and the later processing stages report the malformed node with a proper error message (Can't get image data/size). Patch 2 adds a regression test that builds an external-data FIT, deletes the data-offset property of the second image and re-processes the result with mkimage -F. It asserts that mkimage fails and that the diagnostic is present on stderr; the unfixed tool fails the second assertion since it prints nothing beyond the usage text. Aristo Chen (2): tools: mkimage: fix stale data pointer in fit_import_data() test: py: add regression test for fit_import_data() stale state test/py/tests/test_fit_import_data.py | 89 +++++++++++++++++++++++++++ tools/fit_image.c | 4 +- 2 files changed, 91 insertions(+), 2 deletions(-) create mode 100644 test/py/tests/test_fit_import_data.py -- 2.43.0
