Use wider types for max_old_space_size and co.

Make --max_old_space_size and friends work with values >= 2**31.
Such values did not work reliably (or sometimes not all) due to
signed integer overflow in size computations, which is UB.

Fixes https://github.com/nodejs/node/issues/18786.

Bug: chromium:814138
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
Change-Id: Ibe23cef2417fd5b4a727022b8b0d4b50f1417182
Reviewed-on: https://chromium-review.googlesource.com/927063
Commit-Queue: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51433}

include/v8.h

@@ -6087,13 +6087,13 @@ class V8_EXPORT ResourceConstraints {
 
   // Returns the max semi-space size in MB.
   V8_DEPRECATE_SOON("Use max_semi_space_size_in_kb()",
-                    int max_semi_space_size()) {
-    return static_cast<int>(max_semi_space_size_in_kb_ / 1024);
+                    size_t max_semi_space_size()) {
+    return max_semi_space_size_in_kb_ / 1024;
   }
 
   // Sets the max semi-space size in MB.
   V8_DEPRECATE_SOON("Use set_max_semi_space_size_in_kb(size_t limit_in_kb)",
-                    void set_max_semi_space_size(int limit_in_mb)) {
+                    void set_max_semi_space_size(size_t limit_in_mb)) {
     max_semi_space_size_in_kb_ = limit_in_mb * 1024;
   }
 
@@ -6107,16 +6107,16 @@ class V8_EXPORT ResourceConstraints {
     max_semi_space_size_in_kb_ = limit_in_kb;
   }
 
-  int max_old_space_size() const { return max_old_space_size_; }
-  void set_max_old_space_size(int limit_in_mb) {
+  size_t max_old_space_size() const { return max_old_space_size_; }
+  void set_max_old_space_size(size_t limit_in_mb) {
     max_old_space_size_ = limit_in_mb;
   }
   V8_DEPRECATE_SOON("max_executable_size_ is subsumed by max_old_space_size_",
-                    int max_executable_size() const) {
+                    size_t max_executable_size() const) {
     return max_executable_size_;
   }
   V8_DEPRECATE_SOON("max_executable_size_ is subsumed by max_old_space_size_",
-                    void set_max_executable_size(int limit_in_mb)) {
+                    void set_max_executable_size(size_t limit_in_mb)) {
     max_executable_size_ = limit_in_mb;
   }
   uint32_t* stack_limit() const { return stack_limit_; }
@@ -6127,17 +6127,15 @@ class V8_EXPORT ResourceConstraints {
     code_range_size_ = limit_in_mb;
   }
   size_t max_zone_pool_size() const { return max_zone_pool_size_; }
-  void set_max_zone_pool_size(const size_t bytes) {
-    max_zone_pool_size_ = bytes;
-  }
+  void set_max_zone_pool_size(size_t bytes) { max_zone_pool_size_ = bytes; }
 
  private:
   // max_semi_space_size_ is in KB
   size_t max_semi_space_size_in_kb_;
 
   // The remaining limits are in MB
-  int max_old_space_size_;
-  int max_executable_size_;
+  size_t max_old_space_size_;
+  size_t max_executable_size_;
   uint32_t* stack_limit_;
   size_t code_range_size_;
   size_t max_zone_pool_size_;

src/api.cc

@@ -934,8 +934,7 @@ void ResourceConstraints::ConfigureDefaults(uint64_t physical_memory,
                                             uint64_t virtual_memory_limit) {
   set_max_semi_space_size_in_kb(
       i::Heap::ComputeMaxSemiSpaceSize(physical_memory));
-  set_max_old_space_size(
-      static_cast<int>(i::Heap::ComputeMaxOldGenerationSize(physical_memory)));
+  set_max_old_space_size(i::Heap::ComputeMaxOldGenerationSize(physical_memory));
   set_max_zone_pool_size(i::AccountingAllocator::kMaxPoolSize);
 
   if (virtual_memory_limit > 0 && i::kRequiresCodeRange) {
@@ -950,7 +949,7 @@ void ResourceConstraints::ConfigureDefaults(uint64_t physical_memory,
 void SetResourceConstraints(i::Isolate* isolate,
                             const ResourceConstraints& constraints) {
   size_t semi_space_size = constraints.max_semi_space_size_in_kb();
-  int old_space_size = constraints.max_old_space_size();
+  size_t old_space_size = constraints.max_old_space_size();
   size_t code_range_size = constraints.code_range_size();
   size_t max_pool_size = constraints.max_zone_pool_size();
   if (semi_space_size != 0 || old_space_size != 0 || code_range_size != 0) {

src/flag-definitions.h

@@ -163,6 +163,7 @@ struct MaybeBoolFlag {
 #define DEFINE_INT(nam, def, cmt) FLAG(INT, int, nam, def, cmt)
 #define DEFINE_UINT(nam, def, cmt) FLAG(UINT, unsigned int, nam, def, cmt)
 #define DEFINE_FLOAT(nam, def, cmt) FLAG(FLOAT, double, nam, def, cmt)
+#define DEFINE_SIZE_T(nam, def, cmt) FLAG(SIZE_T, size_t, nam, def, cmt)
 #define DEFINE_STRING(nam, def, cmt) FLAG(STRING, const char*, nam, def, cmt)
 #define DEFINE_ARGS(nam, cmt) \
   FLAG(ARGS, JSArguments, nam, {0 COMMA nullptr}, cmt)
@@ -170,6 +171,7 @@ struct MaybeBoolFlag {
 #define DEFINE_ALIAS_BOOL(alias, nam) FLAG_ALIAS(BOOL, bool, alias, nam)
 #define DEFINE_ALIAS_INT(alias, nam) FLAG_ALIAS(INT, int, alias, nam)
 #define DEFINE_ALIAS_FLOAT(alias, nam) FLAG_ALIAS(FLOAT, double, alias, nam)
+#define DEFINE_ALIAS_SIZE_T(alias, nam) FLAG_ALIAS(SIZE_T, size_t, alias, nam)
 #define DEFINE_ALIAS_STRING(alias, nam) \
   FLAG_ALIAS(STRING, const char*, alias, nam)
 #define DEFINE_ALIAS_ARGS(alias, nam) FLAG_ALIAS(ARGS, JSArguments, alias, nam)
@@ -622,18 +624,18 @@ DEFINE_INT(stress_sampling_allocation_profiler, 0,
            "Enables sampling allocation profiler with X as a sample interval")
 
 // Garbage collections flags.
-DEFINE_INT(min_semi_space_size, 0,
-           "min size of a semi-space (in MBytes), the new space consists of two"
-           "semi-spaces")
-DEFINE_INT(max_semi_space_size, 0,
-           "max size of a semi-space (in MBytes), the new space consists of two"
-           "semi-spaces")
+DEFINE_SIZE_T(min_semi_space_size, 0,
+              "min size of a semi-space (in MBytes), the new space consists of "
+              "two semi-spaces")
+DEFINE_SIZE_T(max_semi_space_size, 0,
+              "max size of a semi-space (in MBytes), the new space consists of "
+              "two semi-spaces")
 DEFINE_INT(semi_space_growth_factor, 2, "factor by which to grow the new space")
 DEFINE_BOOL(experimental_new_space_growth_heuristic, false,
             "Grow the new space based on the percentage of survivors instead "
             "of their absolute value.")
-DEFINE_INT(max_old_space_size, 0, "max size of the old space (in Mbytes)")
-DEFINE_INT(initial_old_space_size, 0, "initial old space size (in Mbytes)")
+DEFINE_SIZE_T(max_old_space_size, 0, "max size of the old space (in Mbytes)")
+DEFINE_SIZE_T(initial_old_space_size, 0, "initial old space size (in Mbytes)")
 DEFINE_BOOL(gc_global, false, "always perform global GCs")
 DEFINE_INT(random_gc_interval, 0,
            "Collect garbage after random(0, X) allocations. It overrides "

src/flags.cc

@@ -5,6 +5,7 @@
 #include "src/flags.h"
 
 #include <cctype>
+#include <cerrno>
 #include <cstdlib>
 #include <sstream>
 
@@ -39,6 +40,7 @@ struct Flag {
     TYPE_INT,
     TYPE_UINT,
     TYPE_FLOAT,
+    TYPE_SIZE_T,
     TYPE_STRING,
     TYPE_ARGS
   };
@@ -81,6 +83,11 @@ struct Flag {
     return reinterpret_cast<double*>(valptr_);
   }
 
+  size_t* size_t_variable() const {
+    DCHECK(type_ == TYPE_SIZE_T);
+    return reinterpret_cast<size_t*>(valptr_);
+  }
+
   const char* string_value() const {
     DCHECK(type_ == TYPE_STRING);
     return *reinterpret_cast<const char**>(valptr_);
@@ -119,6 +126,11 @@ struct Flag {
     return *reinterpret_cast<const double*>(defptr_);
   }
 
+  size_t size_t_default() const {
+    DCHECK(type_ == TYPE_SIZE_T);
+    return *reinterpret_cast<const size_t*>(defptr_);
+  }
+
   const char* string_default() const {
     DCHECK(type_ == TYPE_STRING);
     return *reinterpret_cast<const char* const *>(defptr_);
@@ -142,6 +154,8 @@ struct Flag {
         return *uint_variable() == uint_default();
       case TYPE_FLOAT:
         return *float_variable() == float_default();
+      case TYPE_SIZE_T:
+        return *size_t_variable() == size_t_default();
       case TYPE_STRING: {
         const char* str1 = string_value();
         const char* str2 = string_default();
@@ -173,6 +187,9 @@ struct Flag {
       case TYPE_FLOAT:
         *float_variable() = float_default();
         break;
+      case TYPE_SIZE_T:
+        *size_t_variable() = size_t_default();
+        break;
       case TYPE_STRING:
         set_string_value(string_default(), false);
         break;
@@ -201,6 +218,8 @@ static const char* Type2String(Flag::FlagType type) {
     case Flag::TYPE_UINT:
       return "uint";
     case Flag::TYPE_FLOAT: return "float";
+    case Flag::TYPE_SIZE_T:
+      return "size_t";
     case Flag::TYPE_STRING: return "string";
     case Flag::TYPE_ARGS: return "arguments";
   }
@@ -227,6 +246,9 @@ std::ostream& operator<<(std::ostream& os, const Flag& flag) {  // NOLINT
     case Flag::TYPE_FLOAT:
       os << *flag.float_variable();
       break;
+    case Flag::TYPE_SIZE_T:
+      os << *flag.size_t_variable();
+      break;
     case Flag::TYPE_STRING: {
       const char* str = flag.string_value();
       os << (str ? str : "nullptr");
@@ -358,6 +380,27 @@ static Flag* FindFlag(const char* name) {
   return nullptr;
 }
 
+template <typename T>
+bool TryParseUnsigned(Flag* flag, const char* arg, const char* value,
+                      char** endp, T* out_val) {
+  // We do not use strtoul because it accepts negative numbers.
+  // Rejects values >= 2**63 when T is 64 bits wide but that
+  // seems like an acceptable trade-off.
+  uint64_t max = static_cast<uint64_t>(std::numeric_limits<T>::max());
+  errno = 0;
+  int64_t val = static_cast<int64_t>(strtoll(value, endp, 10));
+  if (val < 0 || static_cast<uint64_t>(val) > max || errno != 0) {
+    PrintF(stderr,
+           "Error: Value for flag %s of type %s is out of bounds "
+           "[0-%" PRIu64
+           "]\n"
+           "Try --help for options\n",
+           arg, Type2String(flag->type()), max);
+    return false;
+  }
+  *out_val = static_cast<T>(val);
+  return true;
+}
 
 // static
 int FlagList::SetFlagsFromCommandLine(int* argc,
@@ -422,27 +465,21 @@ int FlagList::SetFlagsFromCommandLine(int* argc,
         case Flag::TYPE_INT:
           *flag->int_variable() = static_cast<int>(strtol(value, &endp, 10));
           break;
-        case Flag::TYPE_UINT: {
-          // We do not use strtoul because it accepts negative numbers.
-          int64_t val = static_cast<int64_t>(strtoll(value, &endp, 10));
-          if (val < 0 || val > std::numeric_limits<unsigned int>::max()) {
-            PrintF(stderr,
-                   "Error: Value for flag %s of type %s is out of bounds "
-                   "[0-%" PRIu64
-                   "]\n"
-                   "Try --help for options\n",
-                   arg, Type2String(flag->type()),
-                   static_cast<uint64_t>(
-                       std::numeric_limits<unsigned int>::max()));
+        case Flag::TYPE_UINT:
+          if (!TryParseUnsigned(flag, arg, value, &endp,
+                                flag->uint_variable())) {
             return_code = j;
-            break;
           }
-          *flag->uint_variable() = static_cast<unsigned int>(val);
           break;
-        }
         case Flag::TYPE_FLOAT:
           *flag->float_variable() = strtod(value, &endp);
           break;
+        case Flag::TYPE_SIZE_T:
+          if (!TryParseUnsigned(flag, arg, value, &endp,
+                                flag->size_t_variable())) {
+            return_code = j;
+          }
+          break;
         case Flag::TYPE_STRING:
           flag->set_string_value(value ? StrDup(value) : nullptr, true);
           break;

src/heap/heap.cc

@@ -5144,8 +5144,8 @@ bool Heap::ConfigureHeap(size_t max_semi_space_size_in_kb,
 
   // The new space size must be a power of two to support single-bit testing
   // for containment.
-  max_semi_space_size_ = base::bits::RoundUpToPowerOfTwo32(
-      static_cast<uint32_t>(max_semi_space_size_));
+  max_semi_space_size_ = static_cast<size_t>(base::bits::RoundUpToPowerOfTwo64(
+      static_cast<uint64_t>(max_semi_space_size_)));
 
   if (max_semi_space_size_ == kMaxSemiSpaceSizeInKB * KB) {
     // Start with at least 1*MB semi-space on machines with a lot of memory.

src/heap/heap.h

@@ -612,15 +612,15 @@ class Heap {
 #endif
 
   // Semi-space size needs to be a multiple of page size.
-  static const int kMinSemiSpaceSizeInKB =
+  static const size_t kMinSemiSpaceSizeInKB =
       1 * kPointerMultiplier * ((1 << kPageSizeBits) / KB);
-  static const int kMaxSemiSpaceSizeInKB =
+  static const size_t kMaxSemiSpaceSizeInKB =
       16 * kPointerMultiplier * ((1 << kPageSizeBits) / KB);
 
   // The old space size has to be a multiple of Page::kPageSize.
   // Sizes are in MB.
-  static const int kMinOldGenerationSize = 128 * kPointerMultiplier;
-  static const int kMaxOldGenerationSize = 1024 * kPointerMultiplier;
+  static const size_t kMinOldGenerationSize = 128 * kPointerMultiplier;
+  static const size_t kMaxOldGenerationSize = 1024 * kPointerMultiplier;
 
   static const int kTraceRingBufferSize = 512;
   static const int kStacktraceBufferSize = 512;
@@ -1371,10 +1371,10 @@ class Heap {
   size_t MaxOldGenerationSize() { return max_old_generation_size_; }
 
   static size_t ComputeMaxOldGenerationSize(uint64_t physical_memory) {
-    const int old_space_physical_memory_factor = 4;
-    int computed_size =
-        static_cast<int>(physical_memory / i::MB /
-                         old_space_physical_memory_factor * kPointerMultiplier);
+    const size_t old_space_physical_memory_factor = 4;
+    size_t computed_size = static_cast<size_t>(
+        physical_memory / i::MB / old_space_physical_memory_factor *
+        kPointerMultiplier);
     return Max(Min(computed_size, kMaxOldGenerationSize),
                kMinOldGenerationSize);
   }
@@ -1386,11 +1386,11 @@ class Heap {
     uint64_t capped_physical_memory =
         Max(Min(physical_memory, max_physical_memory), min_physical_memory);
     // linearly scale max semi-space size: (X-A)/(B-A)*(D-C)+C
-    int semi_space_size_in_kb =
-        static_cast<int>(((capped_physical_memory - min_physical_memory) *
-                          (kMaxSemiSpaceSizeInKB - kMinSemiSpaceSizeInKB)) /
-                             (max_physical_memory - min_physical_memory) +
-                         kMinSemiSpaceSizeInKB);
+    size_t semi_space_size_in_kb =
+        static_cast<size_t>(((capped_physical_memory - min_physical_memory) *
+                             (kMaxSemiSpaceSizeInKB - kMinSemiSpaceSizeInKB)) /
+                                (max_physical_memory - min_physical_memory) +
+                            kMinSemiSpaceSizeInKB);
     return RoundUp(semi_space_size_in_kb, (1 << kPageSizeBits) / KB);
   }