Simulate NMR API failures: Fix SIGSEGV crashes (#2268)

* Fix SIGSEGV crashes * Revert changes in ebpf_cryptographic_hash_append * Add new line
microsoft · Apr 4, 2023 · 7502790 · 7502790
1 parent dcc2e64
commit 7502790
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Showing 3 changed files with 7 additions and 4 deletions.
diff --git a/libs/execution_context/ebpf_native.c b/libs/execution_context/ebpf_native.c
@@ -361,7 +361,7 @@ _ebpf_native_provider_attach_client_callback(
         goto Done;
     }
     table = (metadata_table_t*)client_registration_instance->NpiSpecificCharacteristics;
-    if (!table->programs || !table->maps) {
+    if (!table || !table->programs || !table->maps) {
         result = EBPF_INVALID_ARGUMENT;
         goto Done;
     }

diff --git a/libs/execution_context/ebpf_program.c b/libs/execution_context/ebpf_program.c
@@ -373,7 +373,8 @@ ebpf_program_load_providers(_Inout_ ebpf_program_t* program)
     }
 
     general_helper_program_data = (ebpf_program_data_t*)program->general_helper_provider_data->data;
-    if (general_helper_program_data->program_type_specific_helper_function_addresses == NULL) {
+    if (!general_helper_program_data ||
+        general_helper_program_data->program_type_specific_helper_function_addresses == NULL) {
         EBPF_LOG_MESSAGE_GUID(
             EBPF_TRACELOG_LEVEL_ERROR,
             EBPF_TRACELOG_KEYWORD_PROGRAM,

diff --git a/libs/platform/user/nmr_impl.cpp b/libs/platform/user/nmr_impl.cpp
@@ -157,9 +157,11 @@ _nmr::client_attach_provider(
 std::optional<_nmr::pending_action_t>
 _nmr::bind(_Inout_ client_registration& client, _Inout_ provider_registration& provider)
 {
+    PNPIID client_pnpi = client.characteristics.ClientRegistrationInstance.NpiId;
+    PNPIID provider_pnpi = provider.characteristics.ProviderRegistrationInstance.NpiId;
+
     // Match on NPI ID.
-    if (*client.characteristics.ClientRegistrationInstance.NpiId !=
-        *provider.characteristics.ProviderRegistrationInstance.NpiId) {
+    if (!client_pnpi || !provider_pnpi || *client_pnpi != *provider_pnpi) {
         return std::nullopt;
     }