Rephrase code to avoid overflow
Code was checking for overflow, but by way of doing the overflowing
calculations. changed from 32-bit to 64-bit calculations to avoid
the overflow.
Bug: 145075076
Test: compilation, to be re-fuzzed
Change-Id: Ic14ce8f22b177802c5166c0bab362b12f25ca353
(cherry picked from commit 1c6217859ed2ad0b27df4b73c1dcdcda5aebe3d5)
diff --git a/libexif/exif-data.c b/libexif/exif-data.c
index adfb512..eb5d49c 100644
--- a/libexif/exif-data.c
+++ b/libexif/exif-data.c
@@ -312,7 +312,10 @@
unsigned int ds, ExifLong o, ExifLong s)
{
/* Sanity checks */
- if ((o + s < o) || (o + s < s) || (o + s > ds) || (o > ds)) {
+ uint64_t o64 = (uint64_t) o;
+ uint64_t s64 = (uint64_t) s;
+ uint64_t ds64 = (uint64_t) ds;
+ if ((o64 + s64) > ds64) {
exif_log (data->priv->log, EXIF_LOG_CODE_DEBUG, "ExifData",
"Bogus thumbnail offset (%u) or size (%u).",
o, s);
