Author: mgorny Date: Mon Jul 1 08:11:10 2019 New Revision: 364780 URL: http://llvm.org/viewvc/llvm-project?rev=364780&view=rev Log: [lldb] [Process/NetBSD] Fix segfault when handling watchpoint
Fix the watchpoint/breakpoint code to search for matching thread entry in m_threads explicitly rather than assuming that it will be present at specified index. The previous code segfault since it wrongly assumed that the index will match LWP ID which was incorrect even for a single thread (where index was 0 and LWP ID was 1). While fixing that off-by-one error would help for this specific task, I believe it is better to be explicit in what we are searching for. Differential Revision: https://reviews.llvm.org/D63791 Modified: lldb/trunk/source/Plugins/Process/NetBSD/NativeProcessNetBSD.cpp Modified: lldb/trunk/source/Plugins/Process/NetBSD/NativeProcessNetBSD.cpp URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Plugins/Process/NetBSD/NativeProcessNetBSD.cpp?rev=364780&r1=364779&r2=364780&view=diff ============================================================================== --- lldb/trunk/source/Plugins/Process/NetBSD/NativeProcessNetBSD.cpp (original) +++ lldb/trunk/source/Plugins/Process/NetBSD/NativeProcessNetBSD.cpp Mon Jul 1 08:11:10 2019 @@ -238,12 +238,25 @@ void NativeProcessNetBSD::MonitorSIGTRAP SetState(StateType::eStateStopped, true); } break; case TRAP_DBREG: { + // Find the thread. + NativeThreadNetBSD* thread = nullptr; + for (const auto &t : m_threads) { + if (t->GetID() == info.psi_lwpid) { + thread = static_cast<NativeThreadNetBSD *>(t.get()); + break; + } + } + if (!thread) { + LLDB_LOG(log, + "thread not found in m_threads, pid = {0}, LWP = {1}", + GetID(), info.psi_lwpid); + break; + } + // If a watchpoint was hit, report it - uint32_t wp_index; - Status error = static_cast<NativeThreadNetBSD &>(*m_threads[info.psi_lwpid]) - .GetRegisterContext() - .GetWatchpointHitIndex( - wp_index, (uintptr_t)info.psi_siginfo.si_addr); + uint32_t wp_index = LLDB_INVALID_INDEX32; + Status error = thread->GetRegisterContext().GetWatchpointHitIndex( + wp_index, (uintptr_t)info.psi_siginfo.si_addr); if (error.Fail()) LLDB_LOG(log, "received error while checking for watchpoint hits, pid = " @@ -258,11 +271,9 @@ void NativeProcessNetBSD::MonitorSIGTRAP } // If a breakpoint was hit, report it - uint32_t bp_index; - error = static_cast<NativeThreadNetBSD &>(*m_threads[info.psi_lwpid]) - .GetRegisterContext() - .GetHardwareBreakHitIndex(bp_index, - (uintptr_t)info.psi_siginfo.si_addr); + uint32_t bp_index = LLDB_INVALID_INDEX32; + error = thread->GetRegisterContext().GetHardwareBreakHitIndex( + bp_index, (uintptr_t)info.psi_siginfo.si_addr); if (error.Fail()) LLDB_LOG(log, "received error while checking for hardware " _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
