Limit the number of frames we try to walk to prevent runaway processors.

Review URL: http://breakpad.appspot.com/175001

git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@672 4c0a9323-5329-0410-9bdc-e9ce6186880e
This commit is contained in:
thestig@chromium.org 2010-08-26 21:38:51 +00:00
parent 64506d2ed7
commit 8e77c078d6
2 changed files with 13 additions and 2 deletions

View file

@ -48,7 +48,6 @@
namespace google_breakpad {
class CallStack;
class CodeModule;
class CodeModules;
class MemoryRegion;
class MinidumpContext;
@ -80,6 +79,9 @@ class Stackwalker {
SymbolSupplier *supplier,
SourceLineResolverInterface *resolver);
static void set_max_frames(u_int32_t max_frames) { max_frames_ = max_frames; }
static u_int32_t max_frames() { return max_frames_; }
protected:
// system_info identifies the operating system, NULL or empty if unknown.
// memory identifies a MemoryRegion that provides the stack memory
@ -146,6 +148,10 @@ class Stackwalker {
// this in order to avoid repeatedly looking them up again within
// one minidump.
set<std::string> no_symbol_modules_;
// The maximum number of frames Stackwalker will walk through.
// This defaults to 1024 to prevent infinite loops.
static u_int32_t max_frames_;
};

View file

@ -55,6 +55,7 @@
namespace google_breakpad {
u_int32_t Stackwalker::max_frames_ = 1024;
Stackwalker::Stackwalker(const SystemInfo *system_info,
MemoryRegion *memory,
@ -120,6 +121,10 @@ bool Stackwalker::Walk(CallStack *stack) {
// Add the frame to the call stack. Relinquish the ownership claim
// over the frame, because the stack now owns it.
stack->frames_.push_back(frame.release());
if (stack->frames_.size() > max_frames_) {
BPLOG(ERROR) << "The stack is over " << max_frames_ << " frames.";
break;
}
// Get the next frame and take ownership.
frame.reset(GetCallerFrame(stack));
@ -166,7 +171,7 @@ Stackwalker* Stackwalker::StackwalkerForCPU(
memory, modules, supplier,
resolver);
break;
case MD_CONTEXT_SPARC:
cpu_stackwalker = new StackwalkerSPARC(system_info,
context->GetContextSPARC(),