libjson-c: backport security fixes

[openwrt/openwrt.git] / package / libs / libjson-c / patches / 001-Protect-array_list_del_idx-against-size_t-overflow.patch

diff --git a/package/libs/libjson-c/patches/001-Protect-array_list_del_idx-against-size_t-overflow.patch b/package/libs/libjson-c/patches/001-Protect-array_list_del_idx-against-size_t-overflow.patch
new file mode 100644 (file)
index 0000000..456fbf3
--- /dev/null
+++ b/package/libs/libjson-c/patches/001-Protect-array_list_del_idx-against-size_t-overflow.patch
@@ -0,0 +1,27 @@
+From 099016b7e8d70a6d5dd814e788bba08d33d48426 Mon Sep 17 00:00:00 2001
+From: Tobias Stoeckmann <tobias@stoeckmann.org>
+Date: Mon, 4 May 2020 19:41:16 +0200
+Subject: [PATCH 1/2] Protect array_list_del_idx against size_t overflow.
+
+If the assignment of stop overflows due to idx and count being
+larger than SIZE_T_MAX in sum, out of boundary access could happen.
+
+It takes invalid usage of this function for this to happen, but
+I decided to add this check so array_list_del_idx is as safe against
+bad usage as the other arraylist functions.
+---
+ arraylist.c | 3 +++
+ 1 file changed, 3 insertions(+)
+
+--- a/arraylist.c
++++ b/arraylist.c
+@@ -135,6 +135,9 @@ array_list_del_idx( struct array_list *a
+ {
+       size_t i, stop;
+ 
++      /* Avoid overflow in calculation with large indices. */
++      if (idx > SIZE_T_MAX - count)
++              return -1;
+       stop = idx + count;
+       if ( idx >= arr->length || stop > arr->length ) return -1;
+       for ( i = idx; i < stop; ++i ) {