Adjust initial memory to handle asan shadow size (#14631)

Without this change any user of ALLOW_MEMORY_GROWTH
with asan would get a rather cryptic error message from
the linker:

 wasm-ld: error: initial memory too small, 278278624 bytes needed

This is because asan increases the memory requirements in
proportion to the max memory, and the max memory defaults
to 2Gb with `ALLOW_MEMORY_GROWTH` enabled.

Also, remove check for `MAXIMUM_MEMORY` == -1 which is no longer
a thing since #14088.

Fixes: #14621

Author: sbc100

emcc.py

@@ -2131,12 +2131,25 @@ def check_memory_setting(setting):
     max_mem = settings.INITIAL_MEMORY
     if settings.ALLOW_MEMORY_GROWTH:
       max_mem = settings.MAXIMUM_MEMORY
-      if max_mem == -1:
-        exit_with_error('ASan requires a finite MAXIMUM_MEMORY')
 
     shadow_size = max_mem // 8
     settings.GLOBAL_BASE = shadow_size
 
+    sanitizer_mem = (shadow_size + webassembly.WASM_PAGE_SIZE) & ~webassembly.WASM_PAGE_SIZE
+    # sanitizers do at least 9 page allocs of a single page during startup.
+    sanitizer_mem += webassembly.WASM_PAGE_SIZE * 9
+    # we also allocate at least 11 "regions". Each region is kRegionSize (2 << 20) but
+    # MmapAlignedOrDieOnFatalError adds another 2 << 20 for alignment.
+    sanitizer_mem += (1 << 21) * 11
+    # When running in the threaded mode asan needs to allocate an array of kMaxNumberOfThreads
+    # (1 << 22) pointers.  See compiler-rt/lib/asan/asan_thread.cpp.
+    if settings.USE_PTHREADS:
+      sanitizer_mem += (1 << 22) * 4
+
+    # Increase the size of the initial memory according to how much memory
+    # we think the sanitizers will use.
+    settings.INITIAL_MEMORY += sanitizer_mem
+
     if settings.SAFE_HEAP:
       # SAFE_HEAP instruments ASan's shadow memory accesses.
       # Since the shadow memory starts at 0, the act of accessing the shadow memory is detected

tests/common.py

@@ -400,7 +400,7 @@ def setUp(self):
     super().setUp()
     self.settings_mods = {}
     self.emcc_args = ['-Werror']
-    self.node_args = []
+    self.node_args = ['--stack-trace-limit=50']
     self.v8_args = []
     self.env = {}
     self.temp_files_before_run = []

tests/test_core.py

@@ -8244,6 +8244,7 @@ def test_pthread_c11_threads(self):
   def test_pthread_cxx_threads(self):
     self.set_setting('PROXY_TO_PTHREAD')
     self.clear_setting('ALLOW_MEMORY_GROWTH')
+    self.set_setting('INITIAL_MEMORY', '64Mb')
     self.set_setting('EXIT_RUNTIME')
     self.do_run_in_out_file_test('pthread/test_pthread_cxx_threads.cpp')
 
@@ -8600,9 +8601,9 @@ def setUp(self):
 strict = make_run('strict', emcc_args=[], settings={'STRICT': 1})
 
 lsan = make_run('lsan', emcc_args=['-fsanitize=leak', '--profiling', '-O2'], settings={'ALLOW_MEMORY_GROWTH': 1})
-asan = make_run('asan', emcc_args=['-fsanitize=address', '--profiling', '-O2'], settings={'ALLOW_MEMORY_GROWTH': 1, 'INITIAL_MEMORY': '500mb'})
+asan = make_run('asan', emcc_args=['-fsanitize=address', '--profiling', '-O2'], settings={'ALLOW_MEMORY_GROWTH': 1})
 asani = make_run('asani', emcc_args=['-fsanitize=address', '--profiling', '-O2', '--pre-js', os.path.join(os.path.dirname(__file__), 'asan-no-leak.js')],
-                 settings={'ALLOW_MEMORY_GROWTH': 1, 'INITIAL_MEMORY': '500mb'})
+                 settings={'ALLOW_MEMORY_GROWTH': 1})
 
 # Experimental modes (not tested by CI)
 lld = make_run('lld', emcc_args=[], settings={'LLD_REPORT_UNDEFINED': 1})

tests/test_other.py

@@ -9177,21 +9177,21 @@ def test_lsan_no_stack_trace(self):
 
   def test_asan_null_deref(self):
     self.do_smart_test(test_file('other/test_asan_null_deref.c'),
-                       emcc_args=['-fsanitize=address', '-sALLOW_MEMORY_GROWTH=1', '-sINITIAL_MEMORY=314572800'],
+                       emcc_args=['-fsanitize=address', '-sALLOW_MEMORY_GROWTH=1'],
                        assert_returncode=NON_ZERO, literals=[
       'AddressSanitizer: null-pointer-dereference on address',
     ])
 
   def test_asan_no_stack_trace(self):
     self.do_smart_test(test_file('other/test_lsan_leaks.c'),
-                       emcc_args=['-fsanitize=address', '-sALLOW_MEMORY_GROWTH=1',  '-sINITIAL_MEMORY=314572800', '-DDISABLE_CONTEXT', '-s', 'EXIT_RUNTIME'],
+                       emcc_args=['-fsanitize=address', '-sALLOW_MEMORY_GROWTH=1', '-DDISABLE_CONTEXT', '-s', 'EXIT_RUNTIME'],
                        assert_returncode=NON_ZERO, literals=[
       'Direct leak of 3427 byte(s) in 3 object(s) allocated from:',
       'SUMMARY: AddressSanitizer: 3427 byte(s) leaked in 3 allocation(s).',
     ])
 
   def test_asan_pthread_stubs(self):
-    self.do_smart_test(test_file('other/test_asan_pthread_stubs.c'), emcc_args=['-fsanitize=address', '-sALLOW_MEMORY_GROWTH=1', '-sINITIAL_MEMORY=314572800'])
+    self.do_smart_test(test_file('other/test_asan_pthread_stubs.c'), emcc_args=['-fsanitize=address', '-sALLOW_MEMORY_GROWTH=1'])
 
   @node_pthreads
   def test_proxy_to_pthread_stack(self):
@@ -9292,7 +9292,7 @@ def test_mmap_and_munmap_anonymous(self):
     self.do_other_test('test_mmap_and_munmap_anonymous.cpp', emcc_args=['-s', 'NO_FILESYSTEM'])
 
   def test_mmap_and_munmap_anonymous_asan(self):
-    self.do_other_test('test_mmap_and_munmap_anonymous.cpp', emcc_args=['-s', 'NO_FILESYSTEM', '-fsanitize=address', '-s', 'ALLOW_MEMORY_GROWTH', '-sINITIAL_MEMORY=314572800'])
+    self.do_other_test('test_mmap_and_munmap_anonymous.cpp', emcc_args=['-s', 'NO_FILESYSTEM', '-fsanitize=address', '-s', 'ALLOW_MEMORY_GROWTH'])
 
   def test_mmap_memorygrowth(self):
     self.do_other_test('test_mmap_memorygrowth.cpp', ['-s', 'ALLOW_MEMORY_GROWTH'])