Merge pull request #14032 from ctiller/api-fuzz

Fix issue whereby fuzzer creates infinitely deep creds (since this is not actually interesting)

test/core/end2end/fuzzers/api_fuzzer.cc

@@ -280,7 +280,12 @@ static grpc_channel_credentials* read_ssl_channel_creds(input_stream* inp) {
   return creds;
 }
 
-static grpc_call_credentials* read_call_creds(input_stream* inp) {
+static grpc_call_credentials* read_call_creds(input_stream* inp, int depth) {
+  if (depth > 64) {
+    // prevent creating infinitely deep call creds
+    end(inp);
+    return nullptr;
+  }
   switch (next_byte(inp)) {
     default:
       end(inp);
@@ -288,8 +293,8 @@ static grpc_call_credentials* read_call_creds(input_stream* inp) {
     case 0:
       return nullptr;
     case 1: {
-      grpc_call_credentials* c1 = read_call_creds(inp);
-      grpc_call_credentials* c2 = read_call_creds(inp);
+      grpc_call_credentials* c1 = read_call_creds(inp, depth + 1);
+      grpc_call_credentials* c2 = read_call_creds(inp, depth + 1);
       if (c1 != nullptr && c2 != nullptr) {
         grpc_call_credentials* out =
             grpc_composite_call_credentials_create(c1, c2, nullptr);
@@ -338,7 +343,7 @@ static grpc_channel_credentials* read_channel_creds(input_stream* inp) {
       break;
     case 1: {
       grpc_channel_credentials* c1 = read_channel_creds(inp);
-      grpc_call_credentials* c2 = read_call_creds(inp);
+      grpc_call_credentials* c2 = read_call_creds(inp, 0);
       if (c1 != nullptr && c2 != nullptr) {
         grpc_channel_credentials* out =
             grpc_composite_channel_credentials_create(c1, c2, nullptr);

tools/run_tests/generated/tests.json

@@ -105417,6 +105417,29 @@
     ], 
     "uses_polling": false
   }, 
+  {
+    "args": [
+      "test/core/end2end/fuzzers/api_fuzzer_corpus/fuzz-input-d2ab5"
+    ], 
+    "ci_platforms": [
+      "linux"
+    ], 
+    "cpu_cost": 0.1, 
+    "exclude_configs": [
+      "tsan"
+    ], 
+    "exclude_iomgrs": [
+      "uv"
+    ], 
+    "flaky": false, 
+    "language": "c", 
+    "name": "api_fuzzer_one_entry", 
+    "platforms": [
+      "mac", 
+      "linux"
+    ], 
+    "uses_polling": false
+  }, 
   {
     "args": [
       "test/core/end2end/fuzzers/api_fuzzer_corpus/poc-c726ee220e980ed6ad17809fd9efe2844ee61555ac08e4f88afd8901cc2dd53a"