Don't read non-readable address ranges during lsan pointer scanning

Summary: This specifically addresses the Mach-O zero page, which we cannot read from.

Reviewers: kubamracek, samsonov, alekseyshl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D32044

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@300456 91177308-0d34-0410-b5e6-96231b3b80d8

7 files changed, 22 insertions, 11 deletions

diff --git a/lib/lsan/lsan_common_mac.cc b/lib/lsan/lsan_common_mac.cc
index d0ee181d0..dfb5ab4cc 100644
--- a/lib/lsan/lsan_common_mac.cc
+++ b/lib/lsan/lsan_common_mac.cc
@@ -108,7 +108,7 @@ void ProcessGlobalRegions(Frontier *frontier) {
 
     for (const __sanitizer::LoadedModule::AddressRange &range :
          modules[i].ranges()) {
-      if (range.executable) continue;
+      if (range.executable || !range.readable) continue;
 
       ScanGlobalRange(range.beg, range.end, frontier);
     }
diff --git a/lib/sanitizer_common/sanitizer_common.cc b/lib/sanitizer_common/sanitizer_common.cc
index 3ef366f4f..471c3ded2 100644
--- a/lib/sanitizer_common/sanitizer_common.cc
+++ b/lib/sanitizer_common/sanitizer_common.cc
@@ -284,9 +284,10 @@ void LoadedModule::clear() {
   }
 }
 
-void LoadedModule::addAddressRange(uptr beg, uptr end, bool executable) {
+void LoadedModule::addAddressRange(uptr beg, uptr end, bool executable,
+                                   bool readable) {
   void *mem = InternalAlloc(sizeof(AddressRange));
-  AddressRange *r = new(mem) AddressRange(beg, end, executable);
+  AddressRange *r = new(mem) AddressRange(beg, end, executable, readable);
   ranges_.push_back(r);
   if (executable && end > max_executable_address_)
     max_executable_address_ = end;
diff --git a/lib/sanitizer_common/sanitizer_common.h b/lib/sanitizer_common/sanitizer_common.h
index 9d367ca80..313f0cfda 100644
--- a/lib/sanitizer_common/sanitizer_common.h
+++ b/lib/sanitizer_common/sanitizer_common.h
@@ -717,7 +717,7 @@ class LoadedModule {
   void set(const char *module_name, uptr base_address, ModuleArch arch,
            u8 uuid[kModuleUUIDSize], bool instrumented);
   void clear();
-  void addAddressRange(uptr beg, uptr end, bool executable);
+  void addAddressRange(uptr beg, uptr end, bool executable, bool readable);
   bool containsAddress(uptr address) const;
 
   const char *full_name() const { return full_name_; }
@@ -732,9 +732,14 @@ class LoadedModule {
     uptr beg;
     uptr end;
     bool executable;
-
-    AddressRange(uptr beg, uptr end, bool executable)
-        : next(nullptr), beg(beg), end(end), executable(executable) {}
+    bool readable;
+
+    AddressRange(uptr beg, uptr end, bool executable, bool readable)
+        : next(nullptr),
+          beg(beg),
+          end(end),
+          executable(executable),
+          readable(readable) {}
   };
 
   const IntrusiveList<AddressRange> &ranges() const { return ranges_; }
diff --git a/lib/sanitizer_common/sanitizer_linux_libcdep.cc b/lib/sanitizer_common/sanitizer_linux_libcdep.cc
index 6fde671f8..25f1e12c0 100644
--- a/lib/sanitizer_common/sanitizer_linux_libcdep.cc
+++ b/lib/sanitizer_common/sanitizer_linux_libcdep.cc
@@ -447,7 +447,9 @@ static int dl_iterate_phdr_cb(dl_phdr_info *info, size_t size, void *arg) {
       uptr cur_beg = info->dlpi_addr + phdr->p_vaddr;
       uptr cur_end = cur_beg + phdr->p_memsz;
       bool executable = phdr->p_flags & PF_X;
-      cur_module.addAddressRange(cur_beg, cur_end, executable);
+      bool readable = phdr->p_flags & PF_R;
+      cur_module.addAddressRange(cur_beg, cur_end, executable,
+                                 readable);
     }
   }
   data->modules->push_back(cur_module);
diff --git a/lib/sanitizer_common/sanitizer_procmaps_common.cc b/lib/sanitizer_common/sanitizer_procmaps_common.cc
index fac3fbdad..67a659010 100644
--- a/lib/sanitizer_common/sanitizer_procmaps_common.cc
+++ b/lib/sanitizer_common/sanitizer_procmaps_common.cc
@@ -141,7 +141,8 @@ void MemoryMappingLayout::DumpListOfModules(
     uptr base_address = (i ? cur_beg : 0) - cur_offset;
     LoadedModule cur_module;
     cur_module.set(cur_name, base_address);
-    cur_module.addAddressRange(cur_beg, cur_end, prot & kProtectionExecute);
+    cur_module.addAddressRange(cur_beg, cur_end, prot & kProtectionExecute,
+                               prot & kProtectionRead);
     modules->push_back(cur_module);
   }
 }
diff --git a/lib/sanitizer_common/sanitizer_procmaps_mac.cc b/lib/sanitizer_common/sanitizer_procmaps_mac.cc
index 2831f2869..be59b481f 100644
--- a/lib/sanitizer_common/sanitizer_procmaps_mac.cc
+++ b/lib/sanitizer_common/sanitizer_procmaps_mac.cc
@@ -262,7 +262,8 @@ void MemoryMappingLayout::DumpListOfModules(
       cur_module->set(cur_name, cur_beg, cur_arch, cur_uuid,
                       current_instrumented_);
     }
-    cur_module->addAddressRange(cur_beg, cur_end, prot & kProtectionExecute);
+    cur_module->addAddressRange(cur_beg, cur_end, prot & kProtectionExecute,
+                                prot & kProtectionRead);
   }
 }
 
diff --git a/lib/sanitizer_common/sanitizer_win.cc b/lib/sanitizer_common/sanitizer_win.cc
index b1a2a53a3..a8a8cd767 100644
--- a/lib/sanitizer_common/sanitizer_win.cc
+++ b/lib/sanitizer_common/sanitizer_win.cc
@@ -553,7 +553,8 @@ void ListOfModules::init() {
     LoadedModule cur_module;
     cur_module.set(module_name, adjusted_base);
     // We add the whole module as one single address range.
-    cur_module.addAddressRange(base_address, end_address, /*executable*/ true);
+    cur_module.addAddressRange(base_address, end_address, /*executable*/ true,
+                               /*readable*/ true);
     modules_.push_back(cur_module);
   }
   UnmapOrDie(hmodules, modules_buffer_size);