media-libs/libexif: rev bump to fix CVE-2018-20030

While here, fix C89 compatibility issue, too.

Bug: https://bugs.gentoo.org/679418
Package-Manager: Portage-2.3.62, Repoman-2.3.12
Signed-off-by: Thomas Deutschmann <whissi@gentoo.org>

3 files changed, 199 insertions, 0 deletions

diff --git a/media-libs/libexif/files/libexif-0.6.21-CVE-2018-20030.patch b/media-libs/libexif/files/libexif-0.6.21-CVE-2018-20030.patch
new file mode 100644
index 000000000000..08179f84b500
--- /dev/null
+++ b/media-libs/libexif/files/libexif-0.6.21-CVE-2018-20030.patch
@@ -0,0 +1,117 @@
+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.
+
+Adjusted for missing https://github.com/libexif/libexif/commit/5d28011c40ec86cf52cffad541093d37c263898a
+
+---
+ 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;
diff --git a/media-libs/libexif/files/libexif-0.6.21-fix-C89-compatibility-issue.patch b/media-libs/libexif/files/libexif-0.6.21-fix-C89-compatibility-issue.patch
new file mode 100644
index 000000000000..c423c9daa61c
--- /dev/null
+++ b/media-libs/libexif/files/libexif-0.6.21-fix-C89-compatibility-issue.patch
@@ -0,0 +1,30 @@
+From 3840e4f1f550e0d113e4ed70bd74f9f798f7e6f8 Mon Sep 17 00:00:00 2001
+From: Dan Fandrich <dan@coneharvesters.com>
+Date: Sat, 13 Jul 2013 13:34:50 -0700
+Subject: [PATCH] Fixed a C89 compatibility issue (bug #117 reported by Guenter
+ Knauf)
+
+---
+ libexif/exif-entry.c | 4 +++-
+ 1 file changed, 3 insertions(+), 1 deletion(-)
+
+diff --git a/libexif/exif-entry.c b/libexif/exif-entry.c
+index 54a90a2..bb42473 100644
+--- a/libexif/exif-entry.c
++++ b/libexif/exif-entry.c
+@@ -1375,12 +1375,14 @@ exif_entry_get_value (ExifEntry *e, char *val, unsigned int maxlen)
+ 	case EXIF_TAG_XP_KEYWORDS:
+ 	case EXIF_TAG_XP_SUBJECT:
+ 	{
++		unsigned short *utf16;
++
+ 		/* Sanity check the size to prevent overflow */
+ 		if (e->size+sizeof(unsigned short) < e->size) break;
+ 
+ 		/* The tag may not be U+0000-terminated , so make a local
+ 		   U+0000-terminated copy before converting it */
+-		unsigned short *utf16 = exif_mem_alloc (e->priv->mem, e->size+sizeof(unsigned short));
++		utf16 = exif_mem_alloc (e->priv->mem, e->size+sizeof(unsigned short));
+ 		if (!utf16) break;
+ 		memcpy(utf16, e->data, e->size);
+ 		utf16[e->size/sizeof(unsigned short)] = 0;
diff --git a/media-libs/libexif/libexif-0.6.21-r3.ebuild b/media-libs/libexif/libexif-0.6.21-r3.ebuild
new file mode 100644
index 000000000000..b9af2c870d3c
--- /dev/null
+++ b/media-libs/libexif/libexif-0.6.21-r3.ebuild
@@ -0,0 +1,52 @@
+# Copyright 1999-2019 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=7
+
+inherit libtool multilib-minimal
+
+DESCRIPTION="Library for parsing, editing, and saving EXIF data"
+HOMEPAGE="https://libexif.github.io/"
+SRC_URI="mirror://sourceforge/${PN}/${P}.tar.bz2"
+
+LICENSE="LGPL-2.1"
+SLOT="0"
+KEYWORDS="~alpha ~amd64 ~arm ~arm64 ~hppa ~ia64 ~mips ~ppc ~ppc64 ~s390 ~sh ~sparc ~x86 ~amd64-fbsd ~x86-fbsd ~amd64-linux ~x86-linux ~ppc-macos ~x64-macos ~x86-macos ~x64-solaris ~x86-solaris"
+IUSE="doc nls static-libs"
+
+RDEPEND="nls? ( virtual/libintl )"
+DEPEND="${RDEPEND}"
+BDEPEND="
+	virtual/pkgconfig
+	doc? ( app-doc/doxygen )
+	nls? ( sys-devel/gettext )"
+
+PATCHES=(
+	"${FILESDIR}"/${PN}-0.6.13-pkgconfig.patch
+	"${FILESDIR}"/${P}-fix-C89-compatibility-issue.patch
+	"${FILESDIR}"/${P}-CVE-2017-7544.patch
+	"${FILESDIR}"/${P}-CVE-2018-20030.patch
+)
+
+src_prepare() {
+	default
+	sed -i -e '/FLAGS=/s:-g::' configure || die #390249
+	elibtoolize # For *-bsd
+}
+
+multilib_src_configure() {
+	ECONF_SOURCE=${S} econf \
+		$(use_enable doc docs) \
+		$(use_enable nls) \
+		$(use_enable static-libs static) \
+		--with-doc-dir="${EPREFIX}"/usr/share/doc/${PF}
+}
+
+multilib_src_install() {
+	emake DESTDIR="${D}" install
+}
+
+multilib_src_install_all() {
+	find "${D}" -name '*.la' -delete || die
+	rm -f "${ED}"/usr/share/doc/${PF}/{ABOUT-NLS,COPYING} || die
+}