libexif/libexif-bugfix-overflow.patch
2020-03-10 15:28:59 +08:00

37 lines
1.4 KiB
Diff

From f9bb9f263fb00f0603ecbefa8957cad24168cbff Mon Sep 17 00:00:00 2001
From: Dan Fandrich <dan@coneharvesters.com>
Date: Wed, 4 Jul 2018 11:06:09 +0200
Subject: [PATCH] Fix a buffer read overflow in exif_entry_get_value
While parsing EXIF_TAG_FOCAL_LENGTH it was possible to read 8 bytes past
the end of a heap buffer. This was detected by the OSS Fuzz project.
Patch from Google.
Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=7344 and
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=14543
---
libexif/exif-entry.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/libexif/exif-entry.c b/libexif/exif-entry.c
index 61260d3..a224ac2 100644
--- a/libexif/exif-entry.c
+++ b/libexif/exif-entry.c
@@ -1040,12 +1040,12 @@ exif_entry_get_value (ExifEntry *e, char *val, unsigned int maxlen)
d = 0.;
entry = exif_content_get_entry (
e->parent->parent->ifd[EXIF_IFD_0], EXIF_TAG_MAKE);
- if (entry && entry->data &&
+ if (entry && entry->data && entry->size >= 7 &&
!strncmp ((char *)entry->data, "Minolta", 7)) {
entry = exif_content_get_entry (
e->parent->parent->ifd[EXIF_IFD_0],
EXIF_TAG_MODEL);
- if (entry && entry->data) {
+ if (entry && entry->data && entry->size >= 8) {
if (!strncmp ((char *)entry->data, "DiMAGE 7", 8))
d = 3.9;
else if (!strncmp ((char *)entry->data, "DiMAGE 5", 8))