From 0cf1a136d861533645b901d5d3f09a1908883a63 Mon Sep 17 00:00:00 2001
From: Roman Azarenko <roman.azarenko@iopsys.eu>
Date: Fri, 25 Aug 2023 10:10:14 +0200
Subject: [PATCH] tools: ensure zeroed padding in external FIT images
Padding the header of an external FIT image is achieved by truncating
the existing temporary FIT file to match the required alignment before
appending image data. Reusing an existing file this way means that the
padding will likely contain a portion of the original data not
overwritten by the new header.
Zero out any data past the end of the new header, and stop at either
the end of the desired padding, or the end of the old FIT file,
whichever comes first.
Fixes: 7946a814a319 ("Revert "mkimage: fit: Do not tail-pad fitImage with external data"")
Signed-off-by: Roman Azarenko <roman.azarenko@iopsys.eu>
Reviewed-by: Simon Glass <sjg@chromium.org>
---
tools/fit_image.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/tools/fit_image.c b/tools/fit_image.c
index 10f36e9342..71e031c855 100644
--- a/tools/fit_image.c
+++ b/tools/fit_image.c
@@ -497,7 +497,7 @@ static int fit_extract_data(struct image_tool_params *params, const char *fname)
{
void *buf = NULL;
int buf_ptr;
- int fit_size, new_size;
+ int fit_size, unpadded_size, new_size, pad_boundary;
int fd;
struct stat sbuf;
void *fdt;
@@ -564,9 +564,13 @@ static int fit_extract_data(struct image_tool_params *params, const char *fname)
/* Pack the FDT and place the data after it */
fdt_pack(fdt);
- new_size = fdt_totalsize(fdt);
- new_size = ALIGN(new_size, align_size);
+ unpadded_size = fdt_totalsize(fdt);
+ new_size = ALIGN(unpadded_size, align_size);
fdt_set_totalsize(fdt, new_size);
+ if (unpadded_size < fit_size) {
+ pad_boundary = new_size < fit_size ? new_size : fit_size;
+ memset(fdt + unpadded_size, 0, pad_boundary - unpadded_size);
+ }
debug("Size reduced from %x to %x\n", fit_size, fdt_totalsize(fdt));
debug("External data size %x\n", buf_ptr);
munmap(fdt, sbuf.st_size);
--
2.39.5