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-rw-r--r--gnu/packages/patches/libexif-CVE-2018-20030.patch120
1 files changed, 0 insertions, 120 deletions
diff --git a/gnu/packages/patches/libexif-CVE-2018-20030.patch b/gnu/packages/patches/libexif-CVE-2018-20030.patch
deleted file mode 100644
index 57e4746b58..0000000000
--- a/gnu/packages/patches/libexif-CVE-2018-20030.patch
+++ /dev/null
@@ -1,120 +0,0 @@
-https://github.com/libexif/libexif/commit/6aa11df549114ebda520dde4cdaea2f9357b2c89.patch
-
-NEWS section was removed
-'12' -> '30' on line 79
-
-From 6aa11df549114ebda520dde4cdaea2f9357b2c89 Mon Sep 17 00:00:00 2001
-From: Dan Fandrich <dan@coneharvesters.com>
-Date: Fri, 12 Oct 2018 16:01:45 +0200
-Subject: [PATCH] Improve deep recursion detection in
- exif_data_load_data_content.
-
-The existing detection was still vulnerable to pathological cases
-causing DoS by wasting CPU. The new algorithm takes the number of tags
-into account to make it harder to abuse by cases using shallow recursion
-but with a very large number of tags. This improves on commit 5d28011c
-which wasn't sufficient to counter this kind of case.
-
-The limitation in the previous fix was discovered by Laurent Delosieres,
-Secunia Research at Flexera (Secunia Advisory SA84652) and is assigned
-the identifier CVE-2018-20030.
----
- NEWS | 1 +
- libexif/exif-data.c | 45 +++++++++++++++++++++++++++++++++++++--------
- 2 files changed, 38 insertions(+), 8 deletions(-)
-
-diff --git a/libexif/exif-data.c b/libexif/exif-data.c
-index e35403d..a6f9c94 100644
---- a/libexif/exif-data.c
-+++ b/libexif/exif-data.c
-@@ -35,6 +35,7 @@
- #include <libexif/olympus/exif-mnote-data-olympus.h>
- #include <libexif/pentax/exif-mnote-data-pentax.h>
-
-+#include <math.h>
- #include <stdlib.h>
- #include <stdio.h>
- #include <string.h>
-@@ -350,6 +351,20 @@ if (data->ifd[(i)]->count) { \
- break; \
- }
-
-+/*! Calculate the recursion cost added by one level of IFD loading.
-+ *
-+ * The work performed is related to the cost in the exponential relation
-+ * work=1.1**cost
-+ */
-+static unsigned int
-+level_cost(unsigned int n)
-+{
-+ static const double log_1_1 = 0.09531017980432493;
-+
-+ /* Adding 0.1 protects against the case where n==1 */
-+ return ceil(log(n + 0.1)/log_1_1);
-+}
-+
- /*! Load data for an IFD.
- *
- * \param[in,out] data #ExifData
-@@ -357,13 +372,13 @@ if (data->ifd[(i)]->count) { \
- * \param[in] d pointer to buffer containing raw IFD data
- * \param[in] ds size of raw data in buffer at \c d
- * \param[in] offset offset into buffer at \c d at which IFD starts
-- * \param[in] recursion_depth number of times this function has been
-- * recursively called without returning
-+ * \param[in] recursion_cost factor indicating how expensive this recursive
-+ * call could be
- */
- static void
- exif_data_load_data_content (ExifData *data, ExifIfd ifd,
- const unsigned char *d,
-- unsigned int ds, unsigned int offset, unsigned int recursion_depth)
-+ unsigned int ds, unsigned int offset, unsigned int recursion_cost)
- {
- ExifLong o, thumbnail_offset = 0, thumbnail_length = 0;
- ExifShort n;
-@@ -378,9 +393,20 @@ exif_data_load_data_content (ExifData *data, ExifIfd ifd,
- if ((((int)ifd) < 0) || ( ((int)ifd) >= EXIF_IFD_COUNT))
- return;
-
-- if (recursion_depth > 30) {
-+ if (recursion_cost > 170) {
-+ /*
-+ * recursion_cost is a logarithmic-scale indicator of how expensive this
-+ * recursive call might end up being. It is an indicator of the depth of
-+ * recursion as well as the potential for worst-case future recursive
-+ * calls. Since it's difficult to tell ahead of time how often recursion
-+ * will occur, this assumes the worst by assuming every tag could end up
-+ * causing recursion.
-+ * The value of 170 was chosen to limit typical EXIF structures to a
-+ * recursive depth of about 6, but pathological ones (those with very
-+ * many tags) to only 2.
-+ */
- exif_log (data->priv->log, EXIF_LOG_CODE_CORRUPT_DATA, "ExifData",
-- "Deep recursion detected!");
-+ "Deep/expensive recursion detected!");
- return;
- }
-
-@@ -422,15 +448,18 @@ exif_data_load_data_content (ExifData *data, ExifIfd ifd,
- switch (tag) {
- case EXIF_TAG_EXIF_IFD_POINTER:
- CHECK_REC (EXIF_IFD_EXIF);
-- exif_data_load_data_content (data, EXIF_IFD_EXIF, d, ds, o, recursion_depth + 1);
-+ exif_data_load_data_content (data, EXIF_IFD_EXIF, d, ds, o,
-+ recursion_cost + level_cost(n));
- break;
- case EXIF_TAG_GPS_INFO_IFD_POINTER:
- CHECK_REC (EXIF_IFD_GPS);
-- exif_data_load_data_content (data, EXIF_IFD_GPS, d, ds, o, recursion_depth + 1);
-+ exif_data_load_data_content (data, EXIF_IFD_GPS, d, ds, o,
-+ recursion_cost + level_cost(n));
- break;
- case EXIF_TAG_INTEROPERABILITY_IFD_POINTER:
- CHECK_REC (EXIF_IFD_INTEROPERABILITY);
-- exif_data_load_data_content (data, EXIF_IFD_INTEROPERABILITY, d, ds, o, recursion_depth + 1);
-+ exif_data_load_data_content (data, EXIF_IFD_INTEROPERABILITY, d, ds, o,
-+ recursion_cost + level_cost(n));
- break;
- case EXIF_TAG_JPEG_INTERCHANGE_FORMAT:
- thumbnail_offset = o;