From 06d326d3a6e343dd5df992afcd3613ea2188d28a Mon Sep 17 00:00:00 2001
From: Jon Smith <jtsmith@pdiarm.com>
Date: Thu, 5 Oct 2017 08:35:02 -0400
Subject: [PATCH] tools: bmp_logo: correctly interpret BMP files with larger
headers
All BMP files were being treated as though they had a 40 byte header.
There are several BMP header formats consisting of additional data.
This was causing some of the header to be read as color information,
skewing the color palette.
Signed-off-by: Jon Smith <jtsmith@pdiarm.com>
---
tools/bmp_logo.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/tools/bmp_logo.c b/tools/bmp_logo.c
index 2247adcc82..55f833fb9b 100644
--- a/tools/bmp_logo.c
+++ b/tools/bmp_logo.c
@@ -76,7 +76,7 @@ int main (int argc, char *argv[])
FILE *fp;
bitmap_t bmp;
bitmap_t *b = &bmp;
- uint16_t data_offset, n_colors;
+ uint16_t data_offset, n_colors, hdr_size;
if (argc < 3) {
usage(argv[0]);
@@ -108,7 +108,12 @@ int main (int argc, char *argv[])
skip_bytes (fp, 8);
if (fread (&data_offset, sizeof (uint16_t), 1, fp) != 1)
error ("Couldn't read bitmap data offset", fp);
- skip_bytes (fp, 6);
+ skip_bytes(fp, 2);
+ if (fread(&hdr_size, sizeof(uint16_t), 1, fp) != 1)
+ error("Couldn't read bitmap header size", fp);
+ if (hdr_size < 40)
+ error("Invalid bitmap header", fp);
+ skip_bytes(fp, 2);
if (fread (&b->width, sizeof (uint16_t), 1, fp) != 1)
error ("Couldn't read bitmap width", fp);
skip_bytes (fp, 2);
@@ -117,7 +122,7 @@ int main (int argc, char *argv[])
skip_bytes (fp, 22);
if (fread (&n_colors, sizeof (uint16_t), 1, fp) != 1)
error ("Couldn't read bitmap colors", fp);
- skip_bytes (fp, 6);
+ skip_bytes(fp, hdr_size - 34);
/*
* Repair endianess.
--
2.39.5