1 files changed, 83 insertions, 0 deletions
diff --git a/package/libs/libjson-c/patches/002-Fix-integer-overflows.patch b/package/libs/libjson-c/patches/002-Fix-integer-overflows.patch
new file mode 100644
index 0000000000..2298785b9c
--- /dev/null
+++ b/package/libs/libjson-c/patches/002-Fix-integer-overflows.patch
@@ -0,0 +1,83 @@
+From d07b91014986900a3a75f306d302e13e005e9d67 Mon Sep 17 00:00:00 2001
+From: Tobias Stoeckmann <tobias@stoeckmann.org>
+Date: Mon, 4 May 2020 19:47:25 +0200
+Subject: [PATCH] Fix integer overflows.
+
+The data structures linkhash and printbuf are limited to 2 GB in size
+due to a signed integer being used to track their current size.
+
+If too much data is added, then size variable can overflow, which is
+an undefined behaviour in C programming language.
+
+Assuming that a signed int overflow just leads to a negative value,
+like it happens on many sytems (Linux i686/amd64 with gcc), then
+printbuf is vulnerable to an out of boundary write on 64 bit systems.
+---
+ linkhash.c |  7 +++++--
+ printbuf.c | 19 ++++++++++++++++---
+ 2 files changed, 21 insertions(+), 5 deletions(-)
+
+--- a/linkhash.c
++++ b/linkhash.c
+@@ -498,7 +498,12 @@ int lh_table_insert(struct lh_table *t,
+ 	unsigned long h, n;
+ 
+ 	t->inserts++;
+-	if(t->count >= t->size * LH_LOAD_FACTOR) lh_table_resize(t, t->size * 2);
++	if(t->count >= t->size * LH_LOAD_FACTOR) {
++		/* Avoid signed integer overflow with large tables. */
++		int new_size = (t->size > INT_MAX / 2) ? INT_MAX : (t->size * 2);
++		if (t->size != INT_MAX)
++			lh_table_resize(t, new_size);
++	}
+ 
+ 	h = t->hash_fn(k);
+ 	n = h % t->size;
+--- a/printbuf.c
++++ b/printbuf.c
+@@ -15,6 +15,7 @@
+ 
+ #include "config.h"
+ 
++#include <limits.h>
+ #include <stdio.h>
+ #include <stdlib.h>
+ #include <string.h>
+@@ -63,7 +64,16 @@ static int printbuf_extend(struct printb
+ 	if (p->size >= min_size)
+ 		return 0;
+ 
+-	new_size = json_max(p->size * 2, 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",
+@@ -78,6 +88,9 @@ static int printbuf_extend(struct printb
+ 
+ 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;
+@@ -94,6 +107,9 @@ int printbuf_memset(struct printbuf *pb,
+ 
+ 	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)
+ 	{