Use heap allocation + valgrind in backend unit test

.github/workflows/ci.yml

@@ -469,6 +469,45 @@ jobs:
           examples: false
           stack: true
           check_namespace: false
+  unit_valgrind:
+    name: Unit tests + valgrind (${{ matrix.target.name }}, ${{ matrix.cflags }})
+    strategy:
+      fail-fast: false
+      matrix:
+        external:
+         - ${{ github.repository_owner != 'pq-code-package' }}
+        target:
+          - runner: ubuntu-latest
+            name: x86_64
+          - runner: ubuntu-24.04-arm
+            name: aarch64
+        cflags: ['-O3', '-Os']
+        exclude:
+          - external: true
+    runs-on: ${{ matrix.target.runner }}
+    steps:
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+      - name: Unit tests under valgrind
+        uses: ./.github/actions/functest
+        with:
+          gh_token: ${{ secrets.GITHUB_TOKEN }}
+          nix-shell: valgrind-varlat_gcc15
+          nix-cache: false
+          opt: opt
+          cflags: "${{ matrix.cflags }} -std=c11 -D_GNU_SOURCE -DMLK_CONFIG_FILE=\\\\\\\"../test/configs/custom_heap_alloc_config.h\\\\\\\""
+          func: false
+          kat: false
+          acvp: false
+          wycheproof: false
+          examples: false
+          stack: false
+          unit: true
+          alloc: false
+          rng_fail: false
+          check_namespace: false
+          # Disable AArch64 SHA3 extension: valgrind cannot emulate it
+          extra_env: "MK_COMPILER_SUPPORTS_SHA3=0"
+          exec_wrapper: "valgrind --error-exitcode=1"
   config_variations:
     name: Non-standard configurations
     strategy:

test/configs/configs.yml

@@ -397,13 +397,29 @@ configs:
     defines:
       MLK_CONFIG_CUSTOM_ALLOC_FREE:
         content: |
+          /* In practice, one could just use aligned_alloc here. However, this
+           * requires aligning up the size to a multiple of the alignment, which
+           * weakens some of the memory-safety tests we run using this config. */
           #define MLK_CONFIG_CUSTOM_ALLOC_FREE
           #if !defined(__ASSEMBLER__)
+          #if defined(_WIN32)
+          #include <malloc.h>
+          #define MLK_CUSTOM_ALLOC(v, T, N) \
+            T *v = (T *)_aligned_malloc(sizeof(T) * (N), MLK_DEFAULT_ALIGN)
+          #define MLK_CUSTOM_FREE(v, T, N) _aligned_free(v)
+          #else
           #include <stdlib.h>
-          #define MLK_CUSTOM_ALLOC(v, T, N)                            \
-            T* v = (T *)aligned_alloc(MLK_DEFAULT_ALIGN,               \
-                                     MLK_ALIGN_UP(sizeof(T) * (N)))
+          static inline void *mlk_posix_memalign(size_t align, size_t sz)
+          {
+            void *ptr = NULL;
+            if (posix_memalign(&ptr, align, sz) != 0)
+              return NULL;
+            return ptr;
+          }
+          #define MLK_CUSTOM_ALLOC(v, T, N) \
+            T *v = (T *)mlk_posix_memalign(MLK_DEFAULT_ALIGN, sizeof(T) * (N))
           #define MLK_CUSTOM_FREE(v, T, N) free(v)
+          #endif /* _WIN32 */
           #endif /* !__ASSEMBLER__ */
 
   - path: examples/basic_deterministic/mlkem_native/mlkem_native_config.h
@@ -449,4 +465,3 @@ configs:
           #endif /* !__ASSEMBLER__ */
       MLK_CONFIG_FILE:
         comment: "/* No need to set this -- we _are_ already in a custom config */"
-

test/configs/custom_heap_alloc_config.h

@@ -498,12 +498,31 @@
  *              code will handle this case and invoke MLK_CUSTOM_FREE.
  *
  *****************************************************************************/
+/* In practice, one could just use aligned_alloc here. However, this
+ * requires aligning up the size to a multiple of the alignment, which
+ * weakens some of the memory-safety tests we run using this config. */
 #define MLK_CONFIG_CUSTOM_ALLOC_FREE
 #if !defined(__ASSEMBLER__)
+#if defined(_WIN32)
+#include <malloc.h>
+#define MLK_CUSTOM_ALLOC(v, T, N) \
+  T *v = (T *)_aligned_malloc(sizeof(T) * (N), MLK_DEFAULT_ALIGN)
+#define MLK_CUSTOM_FREE(v, T, N) _aligned_free(v)
+#else /* _WIN32 */
 #include <stdlib.h>
+static inline void *mlk_posix_memalign(size_t align, size_t sz)
+{
+  void *ptr = NULL;
+  if (posix_memalign(&ptr, align, sz) != 0)
+  {
+    return NULL;
+  }
+  return ptr;
+}
 #define MLK_CUSTOM_ALLOC(v, T, N) \
-  T *v = (T *)aligned_alloc(MLK_DEFAULT_ALIGN, MLK_ALIGN_UP(sizeof(T) * (N)))
+  T *v = (T *)mlk_posix_memalign(MLK_DEFAULT_ALIGN, sizeof(T) * (N))
 #define MLK_CUSTOM_FREE(v, T, N) free(v)
+#endif /* !_WIN32 */
 #endif /* !__ASSEMBLER__ */
 
 

test/mk/components.mk

@@ -33,12 +33,14 @@ MLKEM1024_OBJS = $(call MAKE_OBJS,$(MLKEM1024_DIR),$(SOURCES) $(FIPS202_SRCS))
 $(MLKEM1024_OBJS): CFLAGS += -DMLK_CONFIG_PARAMETER_SET=1024
 
 # Unit test object files - same sources but with MLK_STATIC_TESTABLE=
+UNIT_CFLAGS = -DMLK_STATIC_TESTABLE= -Wno-missing-prototypes
+
 MLKEM512_UNIT_OBJS = $(call MAKE_OBJS,$(MLKEM512_DIR)/unit,$(SOURCES) $(FIPS202_SRCS))
-$(MLKEM512_UNIT_OBJS): CFLAGS += -DMLK_CONFIG_PARAMETER_SET=512 -DMLK_STATIC_TESTABLE= -Wno-missing-prototypes
+$(MLKEM512_UNIT_OBJS): CFLAGS += -DMLK_CONFIG_PARAMETER_SET=512 $(UNIT_CFLAGS)
 MLKEM768_UNIT_OBJS = $(call MAKE_OBJS,$(MLKEM768_DIR)/unit,$(SOURCES) $(FIPS202_SRCS))
-$(MLKEM768_UNIT_OBJS): CFLAGS += -DMLK_CONFIG_PARAMETER_SET=768 -DMLK_STATIC_TESTABLE= -Wno-missing-prototypes
+$(MLKEM768_UNIT_OBJS): CFLAGS += -DMLK_CONFIG_PARAMETER_SET=768 $(UNIT_CFLAGS)
 MLKEM1024_UNIT_OBJS = $(call MAKE_OBJS,$(MLKEM1024_DIR)/unit,$(SOURCES) $(FIPS202_SRCS))
-$(MLKEM1024_UNIT_OBJS): CFLAGS += -DMLK_CONFIG_PARAMETER_SET=1024 -DMLK_STATIC_TESTABLE= -Wno-missing-prototypes
+$(MLKEM1024_UNIT_OBJS): CFLAGS += -DMLK_CONFIG_PARAMETER_SET=1024 $(UNIT_CFLAGS)
 
 # Alloc test object files - same sources but with custom alloc config
 MLKEM512_ALLOC_OBJS = $(call MAKE_OBJS,$(MLKEM512_DIR)/alloc,$(SOURCES) $(FIPS202_SRCS))
@@ -81,9 +83,13 @@ $(MLKEM512_DIR)/test/src/test_alloc.c.o: CFLAGS += -DMLK_CONFIG_FILE=\"../test/c
 $(MLKEM768_DIR)/test/src/test_alloc.c.o: CFLAGS += -DMLK_CONFIG_FILE=\"../test/configs/test_alloc_config.h\"
 $(MLKEM1024_DIR)/test/src/test_alloc.c.o: CFLAGS += -DMLK_CONFIG_FILE=\"../test/configs/test_alloc_config.h\"
 
-$(MLKEM512_DIR)/bin/test_unit512: CFLAGS += -DMLK_STATIC_TESTABLE= -Wno-missing-prototypes
-$(MLKEM768_DIR)/bin/test_unit768: CFLAGS += -DMLK_STATIC_TESTABLE= -Wno-missing-prototypes
-$(MLKEM1024_DIR)/bin/test_unit1024: CFLAGS += -DMLK_STATIC_TESTABLE= -Wno-missing-prototypes
+$(MLKEM512_DIR)/test/src/test_unit.c.o: CFLAGS += $(UNIT_CFLAGS)
+$(MLKEM768_DIR)/test/src/test_unit.c.o: CFLAGS += $(UNIT_CFLAGS)
+$(MLKEM1024_DIR)/test/src/test_unit.c.o: CFLAGS += $(UNIT_CFLAGS)
+
+$(MLKEM512_DIR)/bin/test_unit512: CFLAGS += $(UNIT_CFLAGS)
+$(MLKEM768_DIR)/bin/test_unit768: CFLAGS += $(UNIT_CFLAGS)
+$(MLKEM1024_DIR)/bin/test_unit1024: CFLAGS += $(UNIT_CFLAGS)
 
 # Unit library object files compiled with MLK_STATIC_TESTABLE=
 $(MLKEM512_DIR)/unit_%: CFLAGS += -DMLK_STATIC_TESTABLE= -Wno-missing-prototypes