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Fix a crash in *NetBSD::Factory::Launch
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Authored by krytarowski on Feb 2 2018, 2:10 PM.

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labath
joerg

Commits

rGd85785aa4bf0: Merging r324234: --------------------------------------------------------------…
rG8a4bf06ba994: Fix a crash in *NetBSD::Factory::Launch
rLLDB324234: Fix a crash in *NetBSD::Factory::Launch
rL324327: Merging r324234:
rL324234: Fix a crash in *NetBSD::Factory::Launch

Summary

We cannot call process_up->SetState() inside
the NativeProcessNetBSD::Factory::Launch
function because it triggers a NULL pointer
deference.

The generic code for launching a process in:
GDBRemoteCommunicationServerLLGS::LaunchProcess
sets the m_debugged_process_up pointer after
a successful call to m_process_factory.Launch().
If we attempt to call process_up->SetState()
inside a platform specific Launch function we
end up dereferencing a NULL pointer in
NativeProcessProtocol::GetCurrentThreadID().

Use the proper call process_up->SetState(,false)
that sets notify_delegates to false.

Diff Detail

Repository: rL LLVM

Event Timeline

krytarowski created this revision.Feb 2 2018, 2:10 PM

Herald added a subscriber: llvm-commits. · View Herald TranscriptFeb 2 2018, 2:10 PM

krytarowski edited the summary of this revision. (Show Details)Feb 2 2018, 2:10 PM

(gdb) r
Starting program: /public/llvm-build/bin/lldb-server g \*:1234 -- /usr/bin/look
[New process 15150]

Thread 1 received signal SIGSEGV, Segmentation fault.
lldb_private::NativeProcessProtocol::GetCurrentThreadID (this=0x0) at /public/llvm/tools/lldb/include/lldb/Host/common/NativeProcessProtocol.h:178
178       lldb::tid_t GetCurrentThreadID() { return m_current_thread_id; }
(gdb) bt
#0  lldb_private::NativeProcessProtocol::GetCurrentThreadID (this=0x0) at /public/llvm/tools/lldb/include/lldb/Host/common/NativeProcessProtocol.h:178
#1  0x0000000000600fab in lldb_private::process_gdb_remote::GDBRemoteCommunicationServerLLGS::SendStopReasonForState (this=0x7f7fffffddc0, process_state=lldb::eStateStopped)
    at /public/llvm/tools/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.cpp:1641
#2  0x000000000060135a in lldb_private::process_gdb_remote::GDBRemoteCommunicationServerLLGS::HandleInferiorState_Stopped (this=0x7f7fffffddc0, process=0x7f7ff7b7c000)
    at /public/llvm/tools/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.cpp:835
#3  0x00000000006014d1 in lldb_private::process_gdb_remote::GDBRemoteCommunicationServerLLGS::ProcessStateChanged (this=0x7f7fffffddc0, process=0x7f7ff7b7c000, state=lldb::eStateStopped)
    at /public/llvm/tools/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.cpp:870
#4  0x00000000005412e1 in lldb_private::NativeProcessProtocol::SynchronouslyNotifyProcessStateChanged (this=0x7f7ff7b7c000, state=lldb::eStateStopped)
    at /public/llvm/tools/lldb/source/Host/common/NativeProcessProtocol.cpp:336
#5  0x0000000000542e5f in lldb_private::NativeProcessProtocol::SetState (this=0x7f7ff7b7c000, state=lldb::eStateStopped, notify_delegates=true)
    at /public/llvm/tools/lldb/source/Host/common/NativeProcessProtocol.cpp:422
#6  0x000000000059fc77 in lldb_private::process_netbsd::NativeProcessNetBSD::Factory::Launch (this=0x7f7fffffe3a8, launch_info=..., native_delegate=..., mainloop=...)
    at /public/llvm/tools/lldb/source/Plugins/Process/NetBSD/NativeProcessNetBSD.cpp:114
#7  0x00000000005fd82a in lldb_private::process_gdb_remote::GDBRemoteCommunicationServerLLGS::LaunchProcess (this=0x7f7fffffddc0)
    at /public/llvm/tools/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.cpp:233
#8  0x0000000000418e16 in handle_launch (gdb_server=..., argc=1, argv=0x7f7fffffe6f8) at /public/llvm/tools/lldb/tools/lldb-server/lldb-gdbserver.cpp:195
#9  0x000000000041a228 in main_gdbserver (argc=1, argv=0x7f7fffffe6f8) at /public/llvm/tools/lldb/tools/lldb-server/lldb-gdbserver.cpp:525
#10 0x000000000041befd in main (argc=5, argv=0x7f7fffffe6d8) at /public/llvm/tools/lldb/tools/lldb-server/lldb-server.cpp:58
(gdb)

krytarowski added inline comments.Feb 2 2018, 2:35 PM

source/Plugins/Process/NetBSD/NativeProcessNetBSD.cpp
116	Another option is to call: process_up->SetState(StateType::eStateStopped, false); Both work.

krytarowski updated this revision to Diff 132689.Feb 2 2018, 2:54 PM

krytarowski edited the summary of this revision. (Show Details)

krytarowski marked an inline comment as done.

krytarowski removed a subscriber: llvm-commits.

labath accepted this revision.Feb 5 2018, 2:05 AM

This revision is now accepted and ready to land.Feb 5 2018, 2:05 AM

krytarowski closed this revision.Feb 5 2018, 5:18 AM

Revision Contents

Path

Size

source/

Plugins/

Process/

NetBSD/

NativeProcessNetBSD.cpp

2 lines

Diff 132689

source/Plugins/Process/NetBSD/NativeProcessNetBSD.cpp

Show First 20 Lines • Show All 107 Lines • ▼ Show 20 Lines	std::unique_ptr<NativeProcessNetBSD> process_up(new NativeProcessNetBSD(
Info.GetArchitecture(), mainloop));		Info.GetArchitecture(), mainloop));

status = process_up->ReinitializeThreads();		status = process_up->ReinitializeThreads();
if (status.Fail())		if (status.Fail())
return status.ToError();		return status.ToError();

for (const auto &thread : process_up->m_threads)		for (const auto &thread : process_up->m_threads)
static_cast<NativeThreadNetBSD &>(*thread).SetStoppedBySignal(SIGSTOP);		static_cast<NativeThreadNetBSD &>(*thread).SetStoppedBySignal(SIGSTOP);
process_up->SetState(StateType::eStateStopped);		process_up->SetState(StateType::eStateStopped, false);
krytarowskiAuthorUnsubmitted Done Reply Inline Actions Another option is to call: process_up->SetState(StateType::eStateStopped, false); Both work. krytarowski: Another option is to call: ``` process_up->SetState(StateType::eStateStopped, false); ```…

return std::move(process_up);		return std::move(process_up);
}		}

llvm::Expected<std::unique_ptr<NativeProcessProtocol>>		llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
NativeProcessNetBSD::Factory::Attach(		NativeProcessNetBSD::Factory::Attach(
lldb::pid_t pid, NativeProcessProtocol::NativeDelegate &native_delegate,		lldb::pid_t pid, NativeProcessProtocol::NativeDelegate &native_delegate,
MainLoop &mainloop) const {		MainLoop &mainloop) const {
▲ Show 20 Lines • Show All 793 Lines • Show Last 20 Lines