From 2b8f0ec453715e264637382c27453475635d2ab1 Mon Sep 17 00:00:00 2001
From: alakatos <alakatos@redhat.com>
Date: Tue, 16 May 2023 14:20:56 +0200
Subject: [PATCH] Address CVE-2020-12762   Resolves: rhbz#2203171

---
 libfastjson-CVE-2020-12762.patch | 52 ++++++++++++++++++++++++++++++++
 libfastjson.spec                 |  8 ++++-
 2 files changed, 59 insertions(+), 1 deletion(-)
 create mode 100644 libfastjson-CVE-2020-12762.patch

diff --git a/libfastjson-CVE-2020-12762.patch b/libfastjson-CVE-2020-12762.patch
new file mode 100644
index 0000000..9c8ce74
--- /dev/null
+++ b/libfastjson-CVE-2020-12762.patch
@@ -0,0 +1,52 @@
+diff --git a/printbuf.c b/printbuf.c
+index e9cde11..b02a363 100644
+--- a/printbuf.c
++++ b/printbuf.c
+@@ -13,6 +13,7 @@
+ 
+ #include "config.h"
+ 
++#include <limits.h>
+ #include <stdio.h>
+ #include <stdlib.h>
+ #include <string.h>
+@@ -68,9 +69,16 @@ static int printbuf_extend(struct printbuf *p, int min_size)
+ 	if (p->size >= min_size)
+ 		return 0;
+ 
+-	new_size = p->size * 2;
+-	if (new_size < min_size + 8)
+-		new_size =  min_size + 8;
++	/* Prevent signed integer overflows with large buffers. */
++	if (min_size > INT_MAX - 8)
++		return -1;
++	if (p->size > INT_MAX / 2)
++		new_size = min_size + 8;
++	else {
++		new_size = p->size * 2;
++		if (new_size < min_size + 8)
++			new_size = min_size + 8;
++	}
+ #ifdef PRINTBUF_DEBUG
+ 	MC_DEBUG("printbuf_memappend: realloc "
+ 	  "bpos=%d min_size=%d old_size=%d new_size=%d\n",
+@@ -85,6 +93,9 @@ static int printbuf_extend(struct printbuf *p, int min_size)
+ 
+ int printbuf_memappend(struct printbuf *p, const char *buf, int size)
+ {
++	/* Prevent signed integer overflows with large buffers. */
++	if (size > INT_MAX - p->bpos - 1)
++		return -1;
+ 	if (p->size <= p->bpos + size + 1) {
+ 		if (printbuf_extend(p, p->bpos + size + 1) < 0)
+ 			return -1;
+@@ -136,6 +147,9 @@ int printbuf_memset(struct printbuf *pb, int offset, int charvalue, int len)
+ 
+ 	if (offset == -1)
+ 		offset = pb->bpos;
++	/* Prevent signed integer overflows with large buffers. */
++	if (len > INT_MAX - offset)
++		return -1;
+ 	size_needed = offset + len;
+ 	if (pb->size < size_needed)
+ 	{
diff --git a/libfastjson.spec b/libfastjson.spec
index c7c71cc..b74cf99 100644
--- a/libfastjson.spec
+++ b/libfastjson.spec
@@ -1,12 +1,13 @@
 Name:		libfastjson
 Version:	0.99.9
-Release:	1%{?dist}
+Release:	2%{?dist}
 Summary:	A JSON implementation in C
 License:	MIT
 URL:		https://github.com/rsyslog/libfastjson
 Source0:	http://download.rsyslog.com/libfastjson/libfastjson-%{version}.tar.gz
 
 BuildRequires: autoconf automake libtool
+Patch0: libfastjson-CVE-2020-12762.patch
 
 %description
 LIBFASTJSON implements a reference counting object
@@ -26,6 +27,7 @@ developing applications that use libfastjson.
 
 %prep
 %setup -q
+%patch0 -p1 -b .CVE-2020-12762
 
 for doc in ChangeLog; do
  iconv -f iso-8859-1 -t utf8 $doc > $doc.new &&
@@ -61,6 +63,10 @@ make V=1 check
 %{_libdir}/pkgconfig/libfastjson.pc
 
 %changelog
+* Tue May 16 2023 Attila Lakatos <alakatos@redhat.com> - 0.99.9-2
+- Address CVE-2020-12762
+Resolves: rhbz#2203171
+
 * Thu Apr 22 2021 Attila Lakatos <alakatos@redhat.com> - 0.99.9-1
 - rebase to v0.99.9
 Resolves: rhbz#1936807