[Lldb-commits] [PATCH] D35298: [MainLoop] Fix possible use of an invalid iterator

Phabricator via Phabricator via lldb-commits lldb-commits at lists.llvm.org
Wed Jul 12 05:39:10 PDT 2017


This revision was automatically updated to reflect the committed changes.
Closed by commit rL307782: [MainLoop] Fix possible use of an invalid iterator (authored by petr.pavlu).

Changed prior to commit:
  https://reviews.llvm.org/D35298?vs=106164&id=106187#toc

Repository:
  rL LLVM

https://reviews.llvm.org/D35298

Files:
  lldb/trunk/source/Host/common/MainLoop.cpp


Index: lldb/trunk/source/Host/common/MainLoop.cpp
===================================================================
--- lldb/trunk/source/Host/common/MainLoop.cpp
+++ lldb/trunk/source/Host/common/MainLoop.cpp
@@ -193,10 +193,16 @@
 
 void MainLoop::RunImpl::ProcessEvents() {
 #ifdef FORCE_PSELECT
-  for (const auto &fd : loop.m_read_fds) {
-    if (!FD_ISSET(fd.first, &read_fd_set))
-      continue;
-    IOObject::WaitableHandle handle = fd.first;
+  // Collect first all readable file descriptors into a separate vector and then
+  // iterate over it to invoke callbacks. Iterating directly over
+  // loop.m_read_fds is not possible because the callbacks can modify the
+  // container which could invalidate the iterator.
+  std::vector<IOObject::WaitableHandle> fds;
+  for (const auto &fd : loop.m_read_fds)
+    if (FD_ISSET(fd.first, &read_fd_set))
+      fds.push_back(fd.first);
+
+  for (const auto &handle : fds) {
 #else
   for (const auto &fd : read_fds) {
     if ((fd.revents & POLLIN) == 0)
@@ -209,13 +215,16 @@
     loop.ProcessReadObject(handle);
   }
 
-  for (const auto &entry : loop.m_signals) {
+  std::vector<int> signals;
+  for (const auto &entry : loop.m_signals)
+    if (g_signal_flags[entry.first] != 0)
+      signals.push_back(entry.first);
+
+  for (const auto &signal : signals) {
     if (loop.m_terminate_request)
       return;
-    if (g_signal_flags[entry.first] == 0)
-      continue; // No signal
-    g_signal_flags[entry.first] = 0;
-    loop.ProcessSignal(entry.first);
+    g_signal_flags[signal] = 0;
+    loop.ProcessSignal(signal);
   }
 }
 #endif


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D35298.106187.patch
Type: text/x-patch
Size: 1604 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/lldb-commits/attachments/20170712/a94d1d6d/attachment.bin>


More information about the lldb-commits mailing list