GH-50440: [C++][Gandiva] fix out-of-bounds read in set_error_for_date

cpp/src/gandiva/precompiled/time.cc

@@ -631,7 +631,7 @@ void set_error_for_date(gdv_int32 length, const char* input, const char* msg,
                         int64_t execution_context) {
   int size = length + static_cast<int>(strlen(msg)) + 1;
   char* error = reinterpret_cast<char*>(malloc(size));
-  snprintf(error, size, "%s%s", msg, input);
+  snprintf(error, size, "%s%.*s", msg, length, input);
   gdv_fn_context_set_error_msg(execution_context, error);
   free(error);
 }

cpp/src/gandiva/precompiled/time_test.cc

@@ -18,6 +18,10 @@
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
 
+#include <cstring>
+#include <memory>
+#include <string>
+
 #include "arrow/util/logging_internal.h"
 #include "gandiva/execution_context.h"
 #include "gandiva/precompiled/testing.h"
@@ -59,6 +63,24 @@ TEST(TestTime, TestCastDate) {
   EXPECT_EQ(castDATE_date32(1), 86400000);
 }
 
+TEST(TestTime, TestCastDateInvalidUnterminated) {
+  ExecutionContext context;
+  int64_t context_ptr = reinterpret_cast<int64_t>(&context);
+
+  // The invalid-value error message is built from the raw input pointer. Hold
+  // the input in an exactly-sized heap buffer with no trailing NUL so that
+  // formatting the error must respect `length` instead of scanning for a NUL;
+  // any over-read past the buffer trips AddressSanitizer.
+  const char bytes[] = {'1', '9', '7', '2', '2', '2', '2', '2', '2', '2'};
+  const auto length = static_cast<int32_t>(sizeof(bytes));
+  std::unique_ptr<char[]> input(new char[length]);
+  std::memcpy(input.get(), bytes, length);
+
+  EXPECT_EQ(castDATE_utf8(context_ptr, input.get(), length), 0);
+  EXPECT_EQ(context.get_error(), "Not a valid date value 1972222222");
+  context.Reset();
+}
+
 TEST(TestTime, TestCastTimestamp) {
   ExecutionContext context;
   int64_t context_ptr = reinterpret_cast<int64_t>(&context);