find_mm access of memory outside of allocated space is fixed #31
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
|
I suspect that this will still have an integer overflow when the source string is bigger than 2 GiB. See #32 for a test program that crashes the existing implementation. |
lukem
added a commit
to lukem/mimetic
that referenced
this pull request
Dec 29, 2023
Use std::search() to implement find_bm() instead of using a local implementation of Boyer-Moore. Avoids integer overflow reported in issue tat#31 and PR tat#31. Should fix build problem in issue tat#7. std::search is also faster for the test program in issue tat#31 on a system with an Intel Xeon E-2224 CPU: - gcc 8.5, find_bm(): 3.16s - g++ 8.5, std::search: 2.40s - g++ 13, std::search: 2.16s Experiments using the C++17 std::boyer_moore_searcher or std::boyer_moore_horspool_searcher were also slower than std::search in this experiment.
|
I'm closing it since #33 fixed it, thanks @VladlenPopolitov |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Do you accept pull requests? I use this library in my home project. It has bug with memory access (it is not appear during tests, but appears when memory allocated from heap). Comparison of pointers is not correct, if pointer points outsides of allocated memory and this memory is protected, the program fails with memory access violation (tested on Windows). Also program can receive memory from heap in the end of the memory address space, and comparison of addresses never get true result. Integer arithmetics does not have the problems.