PVS-Studio

It's been two years since we last checked the code of the LLVM project with PVS-Studio, so let's see if PVS-Studio is still the leader among tools for detecting bugs and security weaknesses. We'll do that by scanning the LLVM 8.0.0 release for new bugs.

You must have already guessed from the title that today's article will be focusing on bugs in software source code. But not only that. If you are not only interested in C++ and in reading about bugs in other developers' code but also dig unusual video games and wonder what «roguelikes» are and how you play them, then welcome to read on!

Sometimes people ask the question, which addresses a certain topic but is actually about another thing. As the saying goes, a competently asked question contains half the answer.

Recently I've returned from the JPoint conference, where we first presented our new PVS-Studio analyzer for Java. Interest in static analysis is growing strongly in the last few years, so the audience perceived PVS-Studio enthusiastically. In addition to the positive feedback, as it happens, we had to handle objections. The most frequent objection to the suggestion to try PVS-Studio sounds something like this: «C'mon, why do we try PVS-Studio? We use IntelliJ IDEA, ReSharper, SonarLint and SonarQube. We've run PVS-Studio recently and it found errors, already highlighted by IntelliJ IDEA!»

I just can't help but write a small reply note to this comment. I even have two responses to this objection. And yes, I intentionally stated ReSharper, as there are some questions to our C# analyzer as well. Well, here comes the answer.

Java developers have access to a number of useful tools that help to write high-quality code such as the powerful IDE IntelliJ IDEA, free analyzers SpotBugs, PMD, and the like. The developers working on CUBA Platform have already been using all of these, and this review will show how the project can benefit even more from the use of the static code analyzer PVS-Studio.

This is the second post in our series of articles about the results of checking open-source software working with the RDP protocol. Today we are going to take a look at the rdesktop client and xrdp server.

Wireshark Foundation released the final stable-version of the popular network traffic analyzer — Wireshark 3.0.0. The new release fixes several bugs, it is now possible to analyze the new protocols, apart from that the driver on Npcap WinPcap is replaced. Here is where quoting of the announcement ends and our note about bugs in the project starts off. The projects authors definitely haven't done their best in fixing bugs before the release.

Let's collect hotfixes right now to give a motive in doing a new release :).

Introduction

Wireshark is a well-known tool to capture and analyze network traffic. The program works with the vast majority of known protocols, has intuitive and logical graphical interface, an all-powerful system of filters. Wireshark is cross-platform, works in such OSs, as: Windows, Linux, macOS, Solaris, FreeBSD, NetBSD and many others.

To do the source code analysis, we used PVS-Studio static code analyzer. To analyze the source code, first we needed to compile the project in an OS. The choice was wide not only due to the cross platform nature of the project, but also because of that of the analyzer. I chose macOS for the analysis. You can also run the analyzer under Windows and Linux.

Once in a while we go back to the projects that we have previously checked using PVS-Studio, which results in their descriptions in various articles. Two reasons make these comebacks exciting for us. Firstly, the opportunity to assess the progress of our analyzer. Secondly, monitoring the feedback of the project's authors to our article and the report of errors, which we usually provide them with. Of course, errors can be corrected without our participation. However, it is always nice when our efforts help to make a project better. Roslyn was no exception. The previous article about this project check dates back to December 23, 2015. It's quite a long time, in the view of the progress that our analyzer has made since that time. Since the C# core of the PVS-Studio analyzer is based on Roslyn, it gives us additional interest in this project. As a result, we're as keen as mustard about the code quality of this project. Now let's test it once again and find out some new and interesting issues (but let's hope that nothing significant) that PVS-Studio will be able to find.

The PVS-Studio team has been keeping the blog about the checks of open-source projects by the same-name static code analyzer for many years. To date, more than 300 projects have been checked, the base of errors contains more than 12000 cases. Initially the analyzer was implemented for checking C and C++ code, support of C# was added later. Therefore, from all checked projects the majority (> 80%) accounts for C and C++. Quite recently Java was added to the list of supported languages, which means that there is now a whole new open world for PVS-Studio, so it's time to complement the base with errors from Java projects.

The Java world is vast and varied, so one doesn't even know where to look first when choosing a project to test the new analyzer. Ultimately, the choice fell on the full-text search and analytical engine Elasticsearch. It is quite a successful project, and it's even especially pleasant to find errors in significant projects. So, what defects did PVS-Studio for Java manage to detect? Further talk will be right about the results of the check.

Static analysis methodology involves various technologies. One of them is preprocessing files right before analyzing them. Preprocessed files are created by the compiler that runs in a special working mode. Unfortunately, our long-standing experience of developing a static analyzer shows that this mode is not great for testing. In this note, I'll give the example of a fresh bug in the C++ compiler from Microsoft.

It has been three months since 2018 had ended. For many, it has just flew by, but for us, PVS-Studio developers, it was quite an eventful year. We were working up a sweat, fearlessly competing for spreading the word about static analysis and were searching for errors in open source projects, written in C, C++, C#, and Java languages. In this article, we gathered the top 10 most interesting of them right for you!