Author: Med Ismail Bennani Date: 2020-07-07T23:30:24+02:00 New Revision: 0d7401cf9d5cc0db3de9a8ddb8ea2362d5412d2f
URL: https://github.com/llvm/llvm-project/commit/0d7401cf9d5cc0db3de9a8ddb8ea2362d5412d2f DIFF: https://github.com/llvm/llvm-project/commit/0d7401cf9d5cc0db3de9a8ddb8ea2362d5412d2f.diff LOG: [lldb/api] Add checks for StackFrame::GetRegisterContext calls (NFC) This patch fixes a crash that is happening because of a null pointer dereference in SBFrame. StackFrame::GetRegisterContext says explicitly that you might not get a valid RegisterContext back but the pointer wasn't tested before, resulting in crashes. This should solve the issue. rdar://54462095 Differential Revision: https://reviews.llvm.org/D83343 Signed-off-by: Med Ismail Bennani <medismail.benn...@gmail.com> Added: Modified: lldb/source/API/SBFrame.cpp Removed: ################################################################################ diff --git a/lldb/source/API/SBFrame.cpp b/lldb/source/API/SBFrame.cpp index 5ecf1c537536..81782dbf838f 100644 --- a/lldb/source/API/SBFrame.cpp +++ b/lldb/source/API/SBFrame.cpp @@ -354,15 +354,15 @@ bool SBFrame::SetPC(addr_t new_pc) { std::unique_lock<std::recursive_mutex> lock; ExecutionContext exe_ctx(m_opaque_sp.get(), lock); - StackFrame *frame = nullptr; Target *target = exe_ctx.GetTargetPtr(); Process *process = exe_ctx.GetProcessPtr(); if (target && process) { Process::StopLocker stop_locker; if (stop_locker.TryLock(&process->GetRunLock())) { - frame = exe_ctx.GetFramePtr(); - if (frame) { - ret_val = frame->GetRegisterContext()->SetPC(new_pc); + if (StackFrame *frame = exe_ctx.GetFramePtr()) { + if (RegisterContextSP reg_ctx_sp = frame->GetRegisterContext()) { + ret_val = reg_ctx_sp->SetPC(new_pc); + } } } } @@ -377,15 +377,15 @@ addr_t SBFrame::GetSP() const { std::unique_lock<std::recursive_mutex> lock; ExecutionContext exe_ctx(m_opaque_sp.get(), lock); - StackFrame *frame = nullptr; Target *target = exe_ctx.GetTargetPtr(); Process *process = exe_ctx.GetProcessPtr(); if (target && process) { Process::StopLocker stop_locker; if (stop_locker.TryLock(&process->GetRunLock())) { - frame = exe_ctx.GetFramePtr(); - if (frame) { - addr = frame->GetRegisterContext()->GetSP(); + if (StackFrame *frame = exe_ctx.GetFramePtr()) { + if (RegisterContextSP reg_ctx_sp = frame->GetRegisterContext()) { + addr = reg_ctx_sp->GetSP(); + } } } } @@ -400,15 +400,16 @@ addr_t SBFrame::GetFP() const { std::unique_lock<std::recursive_mutex> lock; ExecutionContext exe_ctx(m_opaque_sp.get(), lock); - StackFrame *frame = nullptr; Target *target = exe_ctx.GetTargetPtr(); Process *process = exe_ctx.GetProcessPtr(); if (target && process) { Process::StopLocker stop_locker; if (stop_locker.TryLock(&process->GetRunLock())) { - frame = exe_ctx.GetFramePtr(); - if (frame) - addr = frame->GetRegisterContext()->GetFP(); + if (StackFrame *frame = exe_ctx.GetFramePtr()) { + if (RegisterContextSP reg_ctx_sp = frame->GetRegisterContext()) { + addr = reg_ctx_sp->GetFP(); + } + } } } _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
