Update univalue subtree

1 files changed, 11 insertions, 0 deletions

diff --git a/src/univalue/lib/univalue_read.cpp b/src/univalue/lib/univalue_read.cpp
index 14834db24d..5c6a1acf75 100644
--- a/src/univalue/lib/univalue_read.cpp
+++ b/src/univalue/lib/univalue_read.cpp
@@ -8,6 +8,14 @@
 #include "univalue.h"
 #include "univalue_utffilter.h"
 
+/*
+ * According to stackexchange, the original json test suite wanted
+ * to limit depth to 22.  Widely-deployed PHP bails at depth 512,
+ * so we will follow PHP's lead, which should be more than sufficient
+ * (further stackexchange comments indicate depth > 32 rarely occurs).
+ */
+static const size_t MAX_JSON_DEPTH = 512;
+
 static bool json_isdigit(int ch)
 {
     return ((ch >= '0') && (ch <= '9'));
@@ -323,6 +331,9 @@ bool UniValue::read(const char *raw, size_t size)
                 stack.push_back(newTop);
             }
 
+            if (stack.size() > MAX_JSON_DEPTH)
+                return false;
+
             if (utyp == VOBJ)
                 setExpect(OBJ_NAME);
             else