Potential double-free in gdImage*Ptr()

Whenever `gdImage*Ptr()` calls `gdImage*Ctx()` and the latter fails, we
must not call `gdDPExtractData()`; otherwise a double-free would
happen.  Since `gdImage*Ctx()` are void functions, and we can't change
that for BC reasons, we're introducing static helpers which are used
internally.

We're adding a regression test for `gdImageJpegPtr()`, but not for
`gdImageGifPtr()` and `gdImageWbmpPtr()` since we don't know how to
trigger failure of the respective `gdImage*Ctx()` calls.

This potential security issue has been reported by Solmaz Salimi (aka.
Rooney).

gd-2.2.5-heap-based-buffer-overflow.patch

@@ -0,0 +1,28 @@
+From 98b2e94e62d873acbcc6d968f1f97af9749fe021 Mon Sep 17 00:00:00 2001
+From: Ondrej Dubaj <odubaj@redhat.com>
+Date: Tue, 4 Jun 2019 10:54:45 +0200
+Subject: [PATCH] heap based buffer overflow in
+ gd_color_match.c:gdImageColorMatch() in libgd as used in imagecolormatch()
+
+---
+ src/gd_color_match.c | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/src/gd_color_match.c b/src/gd_color_match.c
+index f0842b6..a94a841 100755
+--- a/src/gd_color_match.c
++++ b/src/gd_color_match.c
+@@ -31,8 +31,8 @@ BGD_DECLARE(int) gdImageColorMatch (gdImagePtr im1, gdImagePtr im2)
+ 		return -4; /* At least 1 color must be allocated */
+ 	}
+ 
+-	buf = (unsigned long *)gdMalloc(sizeof(unsigned long) * 5 * im2->colorsTotal);
+-	memset (buf, 0, sizeof(unsigned long) * 5 * im2->colorsTotal );
++	buf = (unsigned long *)gdMalloc(sizeof(unsigned long) * 5 * gdMaxColors);
++	memset (buf, 0, sizeof(unsigned long) * 5 * gdMaxColors );
+ 
+ 	for (x=0; x < im1->sx; x++) {
+ 		for( y=0; y<im1->sy; y++ ) {
+-- 
+2.17.1
+

gd-2.2.5-potential-double-free.patch

@@ -0,0 +1,283 @@
+From 4d9d8368d08c3a2be3ea4193b9314fffeddace52 Mon Sep 17 00:00:00 2001
+From: Ondrej Dubaj <odubaj@redhat.com>
+Date: Tue, 4 Jun 2019 13:38:41 +0200
+Subject: [PATCH] Potential double-free in gdImage*Ptr()
+
+Whenever `gdImage*Ptr()` calls `gdImage*Ctx()` and the latter fails, we
+must not call `gdDPExtractData()`; otherwise a double-free would
+happen.  Since `gdImage*Ctx()` are void functions, and we can't change
+that for BC reasons, we're introducing static helpers which are used
+internally.
+
+We're adding a regression test for `gdImageJpegPtr()`, but not for
+`gdImageGifPtr()` and `gdImageWbmpPtr()` since we don't know how to
+trigger failure of the respective `gdImage*Ctx()` calls.
+
+This potential security issue has been reported by Solmaz Salimi (aka.
+Rooney).
+---
+ src/gd_gif_out.c                  | 19 +++++++++++++++----
+ src/gd_jpeg.c                     | 20 ++++++++++++++++----
+ src/gd_wbmp.c                     | 21 ++++++++++++++++++---
+ tests/jpeg/CMakeLists.txt         |  1 +
+ tests/jpeg/Makemodule.am          |  3 ++-
+ tests/jpeg/jpeg_ptr_double_free.c | 31 +++++++++++++++++++++++++++++++
+ 6 files changed, 83 insertions(+), 12 deletions(-)
+ create mode 100644 tests/jpeg/jpeg_ptr_double_free.c
+
+diff --git a/src/gd_gif_out.c b/src/gd_gif_out.c
+index 6fe707d..4a05c09 100755
+--- a/src/gd_gif_out.c
++++ b/src/gd_gif_out.c
+@@ -99,7 +99,7 @@ static void char_init(GifCtx *ctx);
+ static void char_out(int c, GifCtx *ctx);
+ static void flush_char(GifCtx *ctx);
+ 
+-
++static int _gdImageGifCtx(gdImagePtr im, gdIOCtxPtr out);
+ 
+ 
+ /*
+@@ -131,8 +131,11 @@ BGD_DECLARE(void *) gdImageGifPtr(gdImagePtr im, int *size)
+ 	void *rv;
+ 	gdIOCtx *out = gdNewDynamicCtx(2048, NULL);
+ 	if (out == NULL) return NULL;
+-	gdImageGifCtx(im, out);
+-	rv = gdDPExtractData(out, size);
++	if (!_gdImageGifCtx(im, out)) {
++        rv = gdDPExtractData(out, size);
++    } else {
++        rv = NULL;
++    }
+ 	out->gd_free(out);
+ 	return rv;
+ }
+@@ -220,6 +223,12 @@ BGD_DECLARE(void) gdImageGif(gdImagePtr im, FILE *outFile)
+ 
+ */
+ BGD_DECLARE(void) gdImageGifCtx(gdImagePtr im, gdIOCtxPtr out)
++{
++    _gdImageGifCtx(im, out);
++}
++
++/* returns 0 on success, 1 on failure */
++static int _gdImageGifCtx(gdImagePtr im, gdIOCtxPtr out)
+ {
+ 	gdImagePtr pim = 0, tim = im;
+ 	int interlace, BitsPerPixel;
+@@ -231,7 +240,7 @@ BGD_DECLARE(void) gdImageGifCtx(gdImagePtr im, gdIOCtxPtr out)
+ 		based temporary image. */
+ 		pim = gdImageCreatePaletteFromTrueColor(im, 1, 256);
+ 		if(!pim) {
+-			return;
++			return 1;
+ 		}
+ 		tim = pim;
+ 	}
+@@ -247,6 +256,8 @@ BGD_DECLARE(void) gdImageGifCtx(gdImagePtr im, gdIOCtxPtr out)
+ 		/* Destroy palette based temporary image. */
+ 		gdImageDestroy(	pim);
+ 	}
++
++    return 0;
+ }
+ 
+ 
+diff --git a/src/gd_jpeg.c b/src/gd_jpeg.c
+index 271ef46..bd8fc27 100755
+--- a/src/gd_jpeg.c
++++ b/src/gd_jpeg.c
+@@ -123,6 +123,8 @@ static void fatal_jpeg_error(j_common_ptr cinfo)
+ 	exit(99);
+ }
+ 
++static int _gdImageJpegCtx(gdImagePtr im, gdIOCtx *outfile, int quality);
++
+ /*
+  * Write IM to OUTFILE as a JFIF-formatted JPEG image, using quality
+  * QUALITY.  If QUALITY is in the range 0-100, increasing values
+@@ -237,8 +239,11 @@ BGD_DECLARE(void *) gdImageJpegPtr(gdImagePtr im, int *size, int quality)
+ 	void *rv;
+ 	gdIOCtx *out = gdNewDynamicCtx(2048, NULL);
+ 	if (out == NULL) return NULL;
+-	gdImageJpegCtx(im, out, quality);
+-	rv = gdDPExtractData(out, size);
++	if (!_gdImageJpegCtx(im, out, quality)) {
++		rv = gdDPExtractData(out, size);
++	} else {
++		rv = NULL;
++	}
+ 	out->gd_free(out);
+ 	return rv;
+ }
+@@ -259,6 +264,12 @@ void jpeg_gdIOCtx_dest(j_compress_ptr cinfo, gdIOCtx *outfile);
+ 
+ */
+ BGD_DECLARE(void) gdImageJpegCtx(gdImagePtr im, gdIOCtx *outfile, int quality)
++{
++	_gdImageJpegCtx(im, outfile, quality);
++}
++
++/* returns 0 on success, 1 on failure */
++static int _gdImageJpegCtx(gdImagePtr im, gdIOCtx *outfile, int quality)
+ {
+ 	struct jpeg_compress_struct cinfo;
+ 	struct jpeg_error_mgr jerr;
+@@ -293,7 +304,7 @@ BGD_DECLARE(void) gdImageJpegCtx(gdImagePtr im, gdIOCtx *outfile, int quality)
+ 		if(row) {
+ 			gdFree(row);
+ 		}
+-		return;
++		return 1;
+ 	}
+ 
+ 	cinfo.err->emit_message = jpeg_emit_message;
+@@ -334,7 +345,7 @@ BGD_DECLARE(void) gdImageJpegCtx(gdImagePtr im, gdIOCtx *outfile, int quality)
+ 	if(row == 0) {
+ 		gd_error("gd-jpeg: error: unable to allocate JPEG row structure: gdCalloc returns NULL\n");
+ 		jpeg_destroy_compress(&cinfo);
+-		return;
++		return 1;
+ 	}
+ 
+ 	rowptr[0] = row;
+@@ -411,6 +422,7 @@ BGD_DECLARE(void) gdImageJpegCtx(gdImagePtr im, gdIOCtx *outfile, int quality)
+ 	jpeg_finish_compress(&cinfo);
+ 	jpeg_destroy_compress(&cinfo);
+ 	gdFree(row);
++	return 0;
+ }
+ 
+ 
+diff --git a/src/gd_wbmp.c b/src/gd_wbmp.c
+index 0028273..341ff6e 100755
+--- a/src/gd_wbmp.c
++++ b/src/gd_wbmp.c
+@@ -88,6 +88,8 @@ int gd_getin(void *in)
+ 	return (gdGetC((gdIOCtx *)in));
+ }
+ 
++static int _gdImageWBMPCtx(gdImagePtr image, int fg, gdIOCtx *out);
++
+ /*
+ 	Function: gdImageWBMPCtx
+ 
+@@ -100,6 +102,12 @@ int gd_getin(void *in)
+ 		out   - the stream where to write
+ */
+ BGD_DECLARE(void) gdImageWBMPCtx(gdImagePtr image, int fg, gdIOCtx *out)
++{
++	_gdImageWBMPCtx(image, fg, out);
++}
++
++/* returns 0 on success, 1 on failure */
++static int _gdImageWBMPCtx(gdImagePtr image, int fg, gdIOCtx *out)
+ {
+ 	int x, y, pos;
+ 	Wbmp *wbmp;
+@@ -107,7 +115,7 @@ BGD_DECLARE(void) gdImageWBMPCtx(gdImagePtr image, int fg, gdIOCtx *out)
+ 	/* create the WBMP */
+ 	if((wbmp = createwbmp(gdImageSX(image), gdImageSY(image), WBMP_WHITE)) == NULL) {
+ 		gd_error("Could not create WBMP\n");
+-		return;
++		return 1;
+ 	}
+ 
+ 	/* fill up the WBMP structure */
+@@ -123,11 +131,15 @@ BGD_DECLARE(void) gdImageWBMPCtx(gdImagePtr image, int fg, gdIOCtx *out)
+ 
+ 	/* write the WBMP to a gd file descriptor */
+ 	if(writewbmp(wbmp, &gd_putout, out)) {
++		freewbmp(wbmp);
+ 		gd_error("Could not save WBMP\n");
++		return 1;
+ 	}
+ 
+ 	/* des submitted this bugfix: gdFree the memory. */
+ 	freewbmp(wbmp);
++
++	return 0;
+ }
+ 
+ /*
+@@ -271,8 +283,11 @@ BGD_DECLARE(void *) gdImageWBMPPtr(gdImagePtr im, int *size, int fg)
+ 	void *rv;
+ 	gdIOCtx *out = gdNewDynamicCtx(2048, NULL);
+ 	if (out == NULL) return NULL;
+-	gdImageWBMPCtx(im, fg, out);
+-	rv = gdDPExtractData(out, size);
++	if (!_gdImageWBMPCtx(im, fg, out)) {
++		rv = gdDPExtractData(out, size);
++	} else {
++		rv = NULL;
++	}
+ 	out->gd_free(out);
+ 	return rv;
+ }
+diff --git a/tests/jpeg/CMakeLists.txt b/tests/jpeg/CMakeLists.txt
+index 19964b0..a8d8162 100755
+--- a/tests/jpeg/CMakeLists.txt
++++ b/tests/jpeg/CMakeLists.txt
+@@ -2,6 +2,7 @@ IF(JPEG_FOUND)
+ LIST(APPEND TESTS_FILES
+ 	jpeg_empty_file
+ 	jpeg_im2im
++	jpeg_ptr_double_free
+ 	jpeg_null
+ )
+ 
+diff --git a/tests/jpeg/Makemodule.am b/tests/jpeg/Makemodule.am
+index 7e5d317..b89e169 100755
+--- a/tests/jpeg/Makemodule.am
++++ b/tests/jpeg/Makemodule.am
+@@ -2,7 +2,8 @@ if HAVE_LIBJPEG
+ libgd_test_programs += \
+ 	jpeg/jpeg_empty_file \
+ 	jpeg/jpeg_im2im \
+-	jpeg/jpeg_null
++	jpeg/jpeg_null \
++	jpeg/jpeg_ptr_double_free
+ 
+ if HAVE_LIBPNG
+ libgd_test_programs += \
+diff --git a/tests/jpeg/jpeg_ptr_double_free.c b/tests/jpeg/jpeg_ptr_double_free.c
+new file mode 100644
+index 0000000..c80aeb6
+--- /dev/null
++++ b/tests/jpeg/jpeg_ptr_double_free.c
+@@ -0,0 +1,31 @@
++/**
++ * Test that failure to convert to JPEG returns NULL
++ *
++ * We are creating an image, set its width to zero, and pass this image to
++ * `gdImageJpegPtr()` which is supposed to fail, and as such should return NULL.
++ *
++ * See also <https://github.com/libgd/libgd/issues/381>
++ */
++
++
++#include "gd.h"
++#include "gdtest.h"
++
++
++int main()
++{
++    gdImagePtr src, dst;
++    int size;
++
++    src = gdImageCreateTrueColor(1, 10);
++    gdTestAssert(src != NULL);
++
++    src->sx = 0; /* this hack forces gdImageJpegPtr() to fail */
++
++    dst = gdImageJpegPtr(src, &size, 0);
++    gdTestAssert(dst == NULL);
++
++    gdImageDestroy(src);
++
++    return gdNumFailures();
++}
+\ No newline at end of file
+-- 
+2.17.1
+

gd.spec

@@ -9,7 +9,7 @@
 Summary:       A graphics library for quick creation of PNG or JPEG images
 Name:          gd
 Version:       2.2.5
-Release:       7%{?prever}%{?short}%{?dist}
+Release:       8%{?prever}%{?short}%{?dist}
 Group:         System Environment/Libraries
 License:       MIT
 URL:           http://libgd.github.io/
@@ -26,6 +26,10 @@ Patch1:        gd-2.1.0-multilib.patch
 Patch2:        gd-2.2.5-upstream.patch
 # CVE-2018-1000222 - https://github.com/libgd/libgd/commit/ac16bdf2d41724b5a65255d4c28fb0ec46bc42f5
 Patch3:        gd-2.2.5-gdImageBmpPtr-double-free.patch
+# CVE-2019-6977
+Patch4:        gd-2.2.5-heap-based-buffer-overflow.patch
+# CVE-2019-6978
+Patch5:        gd-2.2.5-potential-double-free.patch
 
 BuildRequires: freetype-devel
 BuildRequires: fontconfig-devel
@@ -93,6 +97,8 @@ files for gd, a graphics library for creating PNG and JPEG graphics.
 %patch1 -p1 -b .mlib
 %patch2 -p1 -b .upstream
 %patch3 -p1 -b .gdImageBmpPtr-free
+%patch4 -p1
+%patch5 -p1
 
 : $(perl config/getver.pl)
 
@@ -166,6 +172,12 @@ grep %{version} $RPM_BUILD_ROOT%{_libdir}/pkgconfig/gdlib.pc
 
 
 %changelog
+* Fri Nov 01 2019 odubaj@redhat.com - 2.2.5-8
+- Fixed heap based buffer overflow in gd_color_match.c:gdImageColorMatch() in libgd as used in imagecolormatch()
+- Resolves: RHBZ#1678104 (CVE-2019-6977)
+- Fixed potential double-free in gdImage*Ptr()
+- Resolves: RHBZ#1671391 (CVE-2019-6978)
+
 * Fri Sep 07 2018 mskalick@redhat.com - 2.2.5-7
 - Add missing requires to libimagequent-devel