Problem: The four pointer-resolution loops in u_read_undo() lack
an i != j guard, so a header whose uh_next.seq equals
its own uh_seq resolves uh_next.ptr to itself. On
buffer close, u_freeheader() sees uhp->uh_next.ptr !=
NULL and skips updating b_u_oldhead, so u_blockfree()
dereferences the freed header on the next iteration.
The same pattern applies to uh_prev, uh_alt_next and
uh_alt_prev. A crafted .un~ file in the same directory
as a text file can trigger the use-after-free and
subsequent double-free when the buffer is closed.
(Daniel Cervera)
Solution: Add an i != j guard to each of the four resolution
loops, matching the guard already present in the
duplicate-detection loop above.
closes: vim/vim#20168
Supported by AI
4f610f07b7
Co-authored-by: Christian Brabandt <cb@256bit.org>
Neovim is a project that seeks to aggressively refactor Vim in order to:
- Simplify maintenance and encourage contributions
- Split the work between multiple developers
- Enable advanced UIs without modifications to the core
- Maximize extensibility
See the Introduction wiki page and Roadmap for more information.
Features
- Modern GUIs
- API access from any language including C/C++, C#, Clojure, D, Elixir, Go, Haskell, Java/Kotlin, JavaScript/Node.js, Julia, Lisp, Lua, Perl, Python, Racket, Ruby, Rust
- Embedded, scriptable terminal emulator
- Asynchronous job control
- Shared data (shada) among multiple editor instances
- XDG base directories support
- Compatible with most Vim plugins, including Ruby and Python plugins
See :help nvim-features for the full list, and :help news for noteworthy changes in the latest version!
Install from package
Pre-built packages for Windows, macOS, and Linux are found on the Releases page.
Managed packages are in Homebrew, Debian, Ubuntu, Fedora, Arch Linux, Void Linux, Gentoo, and more!
Install from source
See BUILD.md and supported platforms for details.
The build is CMake-based, but a Makefile is provided as a convenience. After installing the dependencies, run the following command.
make CMAKE_BUILD_TYPE=RelWithDebInfo
sudo make install
To install to a non-default location:
make CMAKE_BUILD_TYPE=RelWithDebInfo CMAKE_INSTALL_PREFIX=/full/path/
make install
CMake hints for inspecting the build:
cmake --build build --target helplists all build targets.build/CMakeCache.txt(orcmake -LAH build/) contains the resolved values of all CMake variables.build/compile_commands.jsonshows the full compiler invocations for each translation unit.
Transitioning from Vim
See :help nvim-from-vim for instructions.
Project layout
├─ cmake/ CMake utils
├─ cmake.config/ CMake defines
├─ cmake.deps/ subproject to fetch and build dependencies (optional)
├─ runtime/ plugins and docs
├─ src/nvim/ application source code (see src/nvim/README.md)
│ ├─ api/ API subsystem
│ ├─ eval/ Vimscript subsystem
│ ├─ event/ event-loop subsystem
│ ├─ generators/ code generation (pre-compilation)
│ ├─ lib/ generic data structures
│ ├─ lua/ Lua subsystem
│ ├─ msgpack_rpc/ RPC subsystem
│ ├─ os/ low-level platform code
│ └─ tui/ built-in UI
└─ test/ tests (see test/README.md)
License
Neovim contributions since b17d96 are licensed under the
Apache 2.0 license, except for contributions copied from Vim (identified by the
vim-patch token). See LICENSE.txt for details.
