When unwinding from the first frame, try to ask the remote debugserver
if this is a mapped/executable region of memory. If it isn't, we've jumped
through a bad pointer and we know how to unwind the stack correctly based
on the ABI.
Previously I had 0x0 special cased but if you jumped to 0x2 on x86_64 one
frame would be skipped because the unwinder would try using the x86_64
ArchDefaultUnwindPlan which relied on the rbp.
Fixes <rdar://problem/10508291>
git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@146477 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp b/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
index 60234ac..eaa0398 100644
--- a/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
+++ b/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
@@ -1108,6 +1108,7 @@
std::string value;
addr_t addr_value;
bool success = true;
+ bool saw_permissions = false;
while (success && response.GetNameColonValue(name, value))
{
if (name.compare ("start") == 0)
@@ -1122,14 +1123,33 @@
if (success)
region_info.GetRange().SetByteSize (addr_value);
}
- else if (name.compare ("permissions") == 0)
+ else if (name.compare ("permissions") == 0 && region_info.GetRange().IsValid())
{
- if (value.find('r') != std::string::npos)
- region_info.AddPermissions (ePermissionsReadable);
- if (value.find('w') != std::string::npos)
- region_info.AddPermissions (ePermissionsWritable);
- if (value.find('x') != std::string::npos)
- region_info.AddPermissions (ePermissionsExecutable);
+ saw_permissions = true;
+ if (region_info.GetRange().Contains (addr))
+ {
+ if (value.find('r') != std::string::npos)
+ region_info.SetReadable (MemoryRegionInfo::eYes);
+ else
+ region_info.SetReadable (MemoryRegionInfo::eNo);
+
+ if (value.find('w') != std::string::npos)
+ region_info.SetWritable (MemoryRegionInfo::eYes);
+ else
+ region_info.SetWritable (MemoryRegionInfo::eNo);
+
+ if (value.find('x') != std::string::npos)
+ region_info.SetExecutable (MemoryRegionInfo::eYes);
+ else
+ region_info.SetExecutable (MemoryRegionInfo::eNo);
+ }
+ else
+ {
+ // The reported region does not contain this address -- we're looking at an unmapped page
+ region_info.SetReadable (MemoryRegionInfo::eNo);
+ region_info.SetWritable (MemoryRegionInfo::eNo);
+ region_info.SetExecutable (MemoryRegionInfo::eNo);
+ }
}
else if (name.compare ("error") == 0)
{
@@ -1141,6 +1161,14 @@
error.SetErrorString(value.c_str());
}
}
+
+ // We got a valid address range back but no permissions -- which means this is an unmapped page
+ if (region_info.GetRange().IsValid() && saw_permissions == false)
+ {
+ region_info.SetReadable (MemoryRegionInfo::eNo);
+ region_info.SetWritable (MemoryRegionInfo::eNo);
+ region_info.SetExecutable (MemoryRegionInfo::eNo);
+ }
}
else
{