SERVER-41689 Adding Scons support for building with libfuzzer

1 files changed, 30 insertions, 1 deletions

diff --git a/SConstruct b/SConstruct
index 47dae18a609..32fe2f81704 100644
--- a/SConstruct
+++ b/SConstruct
@@ -260,6 +260,11 @@ add_option('sanitize',
     metavar='san1,san2,...sanN',
 )
 
+add_option('sanitize-coverage',
+    help='enable selected coverage sanitizers',
+    metavar='cov1,cov2,...covN',
+)
+
 add_option('llvm-symbolizer',
     default='llvm-symbolizer',
     help='name of (or path to) the LLVM symbolizer',
@@ -658,6 +663,7 @@ def variable_tools_converter(val):
         "mongo_benchmark",
         "mongo_integrationtest",
         "mongo_unittest",
+        "mongo_libfuzzer",
         "textfile",
     ]
 
@@ -1015,6 +1021,8 @@ envDict = dict(BUILD_ROOT=buildDir,
                # TODO: Move unittests.txt to $BUILD_DIR, but that requires
                # changes to MCI.
                UNITTEST_LIST='$BUILD_ROOT/unittests.txt',
+               LIBFUZZER_TEST_ALIAS='libfuzzer_tests',
+               LIBFUZZER_TEST_LIST='$BUILD_ROOT/libfuzzer_tests.txt',
                INTEGRATION_TEST_ALIAS='integration_tests',
                INTEGRATION_TEST_LIST='$BUILD_ROOT/integration_tests.txt',
                BENCHMARK_ALIAS='benchmarks',
@@ -2633,6 +2641,7 @@ def doConfigure(myenv):
         using_asan = 'address' in sanitizer_list or using_lsan
         using_tsan = 'thread' in sanitizer_list
         using_ubsan = 'undefined' in sanitizer_list
+        using_fsan = 'fuzzer' in sanitizer_list
 
         if env['MONGO_ALLOCATOR'] in ['tcmalloc', 'tcmalloc-experimental'] and (using_lsan or using_asan):
             # There are multiply defined symbols between the sanitizer and
@@ -2654,6 +2663,15 @@ def doConfigure(myenv):
             if 'address' in sanitizer_list:
                 sanitizer_list.remove('leak')
 
+        if using_fsan:
+            if not myenv.ToolchainIs('clang'):
+                myenv.FatalError("Using the fuzzer sanitizer requires clang")
+            # We can't include the fuzzer flag with the other sanitize flags
+            # The libfuzzer library already has a main function, which will cause the dependencies check
+            # to fail
+            sanitizer_list.remove('fuzzer')
+            sanitizer_list.append('fuzzer-no-link')
+
         sanitizer_option = '-fsanitize=' + ','.join(sanitizer_list)
 
         if AddToCCFLAGSIfSupported(myenv, sanitizer_option):
@@ -2662,6 +2680,15 @@ def doConfigure(myenv):
         else:
             myenv.ConfError('Failed to enable sanitizers with flag: {0}', sanitizer_option )
 
+        if has_option('sanitize-coverage') and using_fsan:
+            sanitize_coverage_list = get_option('sanitize-coverage')
+            sanitize_coverage_option = '-fsanitize-coverage=' + sanitize_coverage_list
+            if AddToCCFLAGSIfSupported(myenv,sanitize_coverage_option):
+                myenv.Append(LINKFLAGS=[sanitize_coverage_option])
+            else:
+                myenv.ConfError('Failed to enable -fsanitize-coverage with flag: {0}', sanitize_coverage_option )
+
+
         blackfiles_map = {
             "address" : myenv.File("#etc/asan.blacklist"),
             "leak" : myenv.File("#etc/asan.blacklist"),
@@ -2733,7 +2760,9 @@ def doConfigure(myenv):
             # By default, undefined behavior sanitizer doesn't stop on
             # the first error. Make it so. Newer versions of clang
             # have renamed the flag.
-            if not AddToCCFLAGSIfSupported(myenv, "-fno-sanitize-recover"):
+            # However, this flag cannot be included when using the fuzzer sanitizer
+            # if we want to suppress errors to uncover new ones.
+            if not using_fsan and not AddToCCFLAGSIfSupported(myenv, "-fno-sanitize-recover"):
                 AddToCCFLAGSIfSupported(myenv, "-fno-sanitize-recover=undefined")
             myenv.AppendUnique(CPPDEFINES=['UNDEFINED_BEHAVIOR_SANITIZER'])