gnu: mupdf: Fix CVE-2017-17858.

* gnu/packages/patches/mupdf-CVE-2017-17858.patch: New file.
* gnu/local.mk (dist_patch_DATA): Add it.
* gnu/packages/pdf.scm (mupdf)[source]: Use it.

2 files changed, 113 insertions, 1 deletions

diff --git a/gnu/packages/patches/mupdf-CVE-2017-17858.patch b/gnu/packages/patches/mupdf-CVE-2017-17858.patch
new file mode 100644
index 0000000000..66df127509
--- /dev/null
+++ b/gnu/packages/patches/mupdf-CVE-2017-17858.patch
@@ -0,0 +1,111 @@
+Fix CVE-2017-17858:
+
+https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-17858
+https://bugs.ghostscript.com/show_bug.cgi?id=698819
+https://github.com/mzet-/Security-Advisories/blob/master/mzet-adv-2017-01.md
+
+Patch copied from upstream source repository:
+
+https://git.ghostscript.com/?p=mupdf.git;a=commit;h=55c3f68d638ac1263a386e0aaa004bb6e8bde731
+
+From 55c3f68d638ac1263a386e0aaa004bb6e8bde731 Mon Sep 17 00:00:00 2001
+From: Sebastian Rasmussen <sebras@gmail.com>
+Date: Mon, 11 Dec 2017 14:09:15 +0100
+Subject: [PATCH] Bugs 698804/698810/698811: Keep PDF object numbers below
+ limit.
+
+This ensures that:
+ * xref tables with objects pointers do not grow out of bounds.
+ * other readers, e.g. Adobe Acrobat can parse PDFs written by mupdf.
+---
+ include/mupdf/pdf/object.h |  3 +++
+ source/pdf/pdf-repair.c    |  5 +----
+ source/pdf/pdf-xref.c      | 21 ++++++++++++---------
+ 3 files changed, 16 insertions(+), 13 deletions(-)
+
+diff --git a/include/mupdf/pdf/object.h b/include/mupdf/pdf/object.h
+index 21ed8595..4177112b 100644
+--- a/include/mupdf/pdf/object.h
++++ b/include/mupdf/pdf/object.h
+@@ -3,6 +3,9 @@
+ 
+ typedef struct pdf_document_s pdf_document;
+ 
++/* Defined in PDF 1.7 according to Acrobat limit. */
++#define PDF_MAX_OBJECT_NUMBER 8388607
++
+ /*
+  * Dynamic objects.
+  * The same type of objects as found in PDF and PostScript.
+diff --git a/source/pdf/pdf-repair.c b/source/pdf/pdf-repair.c
+index ca149bd3..0c29758e 100644
+--- a/source/pdf/pdf-repair.c
++++ b/source/pdf/pdf-repair.c
+@@ -6,9 +6,6 @@
+ 
+ /* Scan file for objects and reconstruct xref table */
+ 
+-/* Define in PDF 1.7 to be 8388607, but mupdf is more lenient. */
+-#define MAX_OBJECT_NUMBER (10 << 20)
+-
+ struct entry
+ {
+ 	int num;
+@@ -436,7 +433,7 @@ pdf_repair_xref(fz_context *ctx, pdf_document *doc)
+ 					break;
+ 				}
+ 
+-				if (num <= 0 || num > MAX_OBJECT_NUMBER)
++				if (num <= 0 || num > PDF_MAX_OBJECT_NUMBER)
+ 				{
+ 					fz_warn(ctx, "ignoring object with invalid object number (%d %d R)", num, gen);
+ 					goto have_next_token;
+diff --git a/source/pdf/pdf-xref.c b/source/pdf/pdf-xref.c
+index 00586dbd..6284e70b 100644
+--- a/source/pdf/pdf-xref.c
++++ b/source/pdf/pdf-xref.c
+@@ -868,11 +868,12 @@ pdf_read_old_xref(fz_context *ctx, pdf_document *doc, pdf_lexbuf *buf)
+ 			fz_seek(ctx, file, -(2 + (int)strlen(s)), SEEK_CUR);
+ 		}
+ 
+-		if (ofs < 0)
+-			fz_throw(ctx, FZ_ERROR_GENERIC, "out of range object num in xref: %d", (int)ofs);
+-		if (ofs > INT64_MAX - len)
+-			fz_throw(ctx, FZ_ERROR_GENERIC, "xref section object numbers too big");
+-
++		if (ofs < 0 || ofs > PDF_MAX_OBJECT_NUMBER
++				|| len < 0 || len > PDF_MAX_OBJECT_NUMBER
++				|| ofs + len - 1 > PDF_MAX_OBJECT_NUMBER)
++		{
++			fz_throw(ctx, FZ_ERROR_GENERIC, "xref subsection object numbers are out of range");
++		}
+ 		/* broken pdfs where size in trailer undershoots entries in xref sections */
+ 		if (ofs + len > xref_len)
+ 		{
+@@ -933,10 +934,8 @@ pdf_read_new_xref_section(fz_context *ctx, pdf_document *doc, fz_stream *stm, in
+ 	pdf_xref_entry *table;
+ 	int i, n;
+ 
+-	if (i0 < 0 || i1 < 0 || i0 > INT_MAX - i1)
+-		fz_throw(ctx, FZ_ERROR_GENERIC, "negative xref stream entry index");
+-	//if (i0 + i1 > pdf_xref_len(ctx, doc))
+-	//	fz_throw(ctx, FZ_ERROR_GENERIC, "xref stream has too many entries");
++	if (i0 < 0 || i0 > PDF_MAX_OBJECT_NUMBER || i1 < 0 || i1 > PDF_MAX_OBJECT_NUMBER || i0 + i1 - 1 > PDF_MAX_OBJECT_NUMBER)
++		fz_throw(ctx, FZ_ERROR_GENERIC, "xref subsection object numbers are out of range");
+ 
+ 	table = pdf_xref_find_subsection(ctx, doc, i0, i1);
+ 	for (i = i0; i < i0 + i1; i++)
+@@ -2086,6 +2085,10 @@ pdf_create_object(fz_context *ctx, pdf_document *doc)
+ 	/* TODO: reuse free object slots by properly linking free object chains in the ofs field */
+ 	pdf_xref_entry *entry;
+ 	int num = pdf_xref_len(ctx, doc);
++
++	if (num > PDF_MAX_OBJECT_NUMBER)
++		fz_throw(ctx, FZ_ERROR_GENERIC, "too many objects stored in pdf");
++
+ 	entry = pdf_get_incremental_xref_entry(ctx, doc, num);
+ 	entry->type = 'f';
+ 	entry->ofs = -1;
+-- 
+2.16.1
+
diff --git a/gnu/packages/pdf.scm b/gnu/packages/pdf.scm
index 96773da717..9730e6150c 100644
--- a/gnu/packages/pdf.scm
+++ b/gnu/packages/pdf.scm
@@ -584,7 +584,8 @@ extracting content or merging files.")
         (method url-fetch)
         (uri (string-append "https://mupdf.com/downloads/archive/"
                             name "-" version "-source.tar.xz"))
-        (patches (search-patches "mupdf-build-with-latest-openjpeg.patch"))
+        (patches (search-patches "mupdf-build-with-latest-openjpeg.patch"
+                                 "mupdf-CVE-2017-17858.patch"))
         (sha256
          (base32
           "0b9j0gqbc3jhmx87r6idcsh8lnb30840c3hyx6dk2gdjqqh3hysp"))