Add support for Linux memory mapping stream and remove ELF header usage

when checking exploitability rating.

Linux minidumps do not support MD_MEMORY_INFO_LIST_STREAM, meaning the
processor cannot retrieve its memory mappings. However, it has its own
stream, MD_LINUX_MAPS, which contains memory mappings specific to Linux
(it contains the contents of /proc/self/maps). This CL allows the minidump
to gather information from the memory mappings for Linux minidumps.

In addition, exploitability rating for Linux dumps now use memory mappings
instead of checking the ELF headers of binaries. The basis for the change
is that checking the ELF headers requires the minidumps to store the memory
from the ELF headers, while the memory mapping data is already present,
meaning the size of a minidump will be unchanged.

As a result, of removing ELF header analysis, two unit tests have been removed.
Arguably, the cases that those unit tests check do not merit a high
exploitability rating and do not warrant a solid conclusion that was given
earlier.

R=ivanpe@chromium.org

Review URL: https://codereview.chromium.org/1251593007

git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1476 4c0a9323-5329-0410-9bdc-e9ce6186880e

1 files changed, 0 insertions, 51 deletions

diff --git a/src/processor/exploitability_linux.h b/src/processor/exploitability_linux.h
index 2deb4991..6332b074 100644
--- a/src/processor/exploitability_linux.h
+++ b/src/processor/exploitability_linux.h
@@ -43,17 +43,6 @@
 
 namespace google_breakpad {
 
-enum LinuxArchitectureType {
-  // A 32-bit Linux architecture.
-  LINUX_32_BIT,
-
-  // A 64-bit Linux architecture.
-  LINUX_64_BIT,
-
-  // Some other architecture that is not Linux.
-  UNSUPPORTED_ARCHITECTURE
-};
-
 class ExploitabilityLinux : public Exploitability {
  public:
   ExploitabilityLinux(Minidump *dump,
@@ -69,46 +58,6 @@ class ExploitabilityLinux : public Exploitability {
   // This method checks the exception that triggered the creation of the
   // minidump and reports whether the exception suggests no exploitability.
   bool BenignCrashTrigger(const MDRawExceptionStream *raw_exception_stream);
-
-  // Checks if the minidump architecture is 32-bit or 64-bit.
-  LinuxArchitectureType ArchitectureType();
-
-  // Loads ELF header data of the module present in the given memory
-  // region into the scoped pointer.
-  // This method takes a scoped pointer in which the ELF header data is
-  // loaded, the memory region containing the ELF header, and the base
-  // address of the ELF header.
-  template<typename T>
-  void LoadElfHeader(MinidumpMemoryRegion *memory,
-                     uint64_t base_address,
-                     T *header) {
-    for (size_t i = 0; i < sizeof(T); i++) {
-      uint8_t my_byte = 0;
-      memory->GetMemoryAtAddress(base_address + i, &my_byte);
-      *(reinterpret_cast<char *>(header) + i) = my_byte;
-    }
-  }
-
-  // Loads the Program Header Table of the module present in the given
-  // memory region into the scoped array.
-  // This method takes a scoped array in which the header table data is
-  // loaded, the memory region containing the table, the base address of
-  // the program header table, and the number of entries in the table.
-  template<typename T>
-  void LoadElfHeaderTable(MinidumpMemoryRegion *memory,
-                          uint64_t base_address,
-                          uint16_t e_phnum,
-                          T table[]) {
-    uint64_t offset = 0;
-    for (size_t i = 0; i < e_phnum; i++) {
-      T *entry = &table[i];
-      for (size_t j = 0; j < sizeof(T); j++) {
-        uint8_t my_byte = 0;
-        memory->GetMemoryAtAddress(base_address + offset++, &my_byte);
-        *(reinterpret_cast<char *>(entry) + j) = my_byte;
-      }
-    }
-  }
 };
 
 }  // namespace google_breakpad