Enable malloc checks

We only use malloc in one place, when we hand a pointer off to PAM.
Ignore that one issue, and enable the check.

Signed-off-by: Ed Tanous <edtanous@google.com>
Change-Id: I37c41c193bae1bab370b03944617c642df0179fc
diff --git a/.clang-tidy b/.clang-tidy
index b708a70..c15af94 100644
--- a/.clang-tidy
+++ b/.clang-tidy
@@ -204,6 +204,7 @@
 cppcoreguidelines-init-variables,
 cppcoreguidelines-interfaces-global-init,
 cppcoreguidelines-macro-usage,
+cppcoreguidelines-no-malloc,
 cppcoreguidelines-pro-bounds-array-to-pointer-decay,
 cppcoreguidelines-pro-bounds-pointer-arithmetic,
 cppcoreguidelines-pro-type-const-cast,
diff --git a/include/pam_authenticate.hpp b/include/pam_authenticate.hpp
index 10d9116..ca8c8d3 100644
--- a/include/pam_authenticate.hpp
+++ b/include/pam_authenticate.hpp
@@ -57,9 +57,11 @@
         std::strncpy(pass, appPass, appPassSize + 1);
 
         size_t numMsgSize = static_cast<size_t>(numMsg);
+        // NOLINTNEXTLINE(cppcoreguidelines-no-malloc)
         void* ptr = calloc(numMsgSize, sizeof(struct pam_response));
         if (ptr == nullptr)
         {
+            // NOLINTNEXTLINE(cppcoreguidelines-no-malloc)
             free(pass);
             return PAM_BUF_ERR;
         }