mirror of
https://github.com/llvm/llvm-project.git
synced 2025-05-08 19:56:06 +00:00

Summary: I have found a way to segfault lldb in 7 keystrokes! Steps to reproduce: 1) Launch lldb 2) Type `print` and hit enter. lldb will now prompt you to type a list of expressions, followed by an empty line. 3) Hit enter, indicating the end of your input. 4) Segfault! After some investigation, I've found the issue in Host/common/Editline.cpp. Editline::MoveCursor() relies on m_input_lines not being empty when the `to` argument is CursorPosition::BlockEnd. This scenario, as far as I can tell, occurs in one specific instance: In Editline::EndOrAddLineCommand() when the list of lines being processed contains exactly one string (""). Meeting this condition is fairly simple, I have posted steps to reproduce above. Reviewers: krytarowski, zturner, labath Reviewed By: labath Subscribers: scott.smith, lldb-commits Differential Revision: https://reviews.llvm.org/D32421 Patch by Alex Langford. llvm-svn: 302225