Issue #20387 has been updated by kjtsanaktsidis (KJ Tsanaktsidis). Having spent a bit of time on this yesterday - I think there's some value in judiciously using ASAN versions _some_ dependencies, but not the whole tree. I think the best approach for these dependencies is simply to statically link them; that way, the built Ruby will be runnable exactly as it is now (no need to apt install special asan'd packages for consumers of setup-ruby). I opened a PR in https://github.com/ruby/ruby-dev-builder/pull/10 to compile Ruby with ASAN, and selected these three dependencies to also compile with ASAN: * OpenSSL - because we use it in non-GVL contexts to perform IO, so we want to catch if any buffers are GC'd and poisoned while OpenSSL is still using them * libffi - because the whole point of it is to make arbitrary calls to C (in fact, pure-ruby code using fiddle or the ffi gem might even benefit from an ASAN'd libffi to find mistakes in Ruby code) * libyaml - because it's often used to handle untrusted data and it's pretty small. That seemed like a good balance to me. I've already found a bug in the OpenSSL gem's test suite because of this: https://github.com/ruby/openssl/pull/762
Of course C extensions from gems should also be compiled with ASAN (does that already work automatically?).
It should do yes, because the `CFLAGS`/`CC` get saved in rbconfig (but i'm going to do some testing with that ruby-dev-builder branch to make sure that works in the way I expect
How do other projects use ASAN? They must have similar situations regarding dependencies compiled or not with ASAN.
I really did try and look at how Firefox, Chromium and LLVM configure their build environments. But it was _wickedly_ complicated and opaque. It doesn't _look_ to me like they compile with ASAN'd dependencies, but i'm not really sure. ---------------------------------------- Misc #20387: Meta-ticket for ASAN support https://bugs.ruby-lang.org/issues/20387#change-108579 * Author: kjtsanaktsidis (KJ Tsanaktsidis) * Status: Assigned * Assignee: kjtsanaktsidis (KJ Tsanaktsidis) ---------------------------------------- I was asked to provide a bit of information about the current status of ASAN in CRuby, so I thought I'd open this meta-ticket to track all of the work I've been performing on fixing up address sanitizer support. So far, I have fixed the following issues related to ASAN support: * https://bugs.ruby-lang.org/issues/20001 + https://github.com/ruby/ruby/pull/9505, which dealt with two main themes: - Pushing the logic for capturing the start of the machine stack much closer to the top of the call stack, so that VALUEs stored close to the top of the machine stack get marked properly - Marking VALUEs stored on ASAN fake stacks during machine stack marking * https://bugs.ruby-lang.org/issues/20220 + https://github.com/ruby/ruby/pull/9734, which made M:N threading notify ASAN about stack switches in the same way that fibers do - Note: ASAN still doesn't work with M:N threading, but that actually has nothing to do with ASAN; it's because the most recent versions of Clang which are needed for ASAN just don't work with M:N threading either. See https://bugs.ruby-lang.org/issues/20243 for more info about that. * https://bugs.ruby-lang.org/issues/20273 + https://github.com/ruby/ruby/pull/10012, which disables `callcc` (and the associated tests) when ASAN is enabled - callcc is very rarely used in real code and the way it works is just fundamentally incompatible with ASAN (it performs longjmp's which I think are technically undefined behaviour) * https://bugs.ruby-lang.org/issues/20221 + https://github.com/ruby/ruby/pull/9865, which ignore some global symbols that ASAN defines from the global symbol leak checker * https://bugs.ruby-lang.org/issues/20274 + https://github.com/ruby/ruby/pull/10087, which ignores some false positive tests about memory leaks when ASAN is enabl * I updated the ASAN docs in https://github.com/ruby/ruby/pull/9922 to more closely reflect current reality The current state of things is that, by following the instructions in https://github.com/ruby/ruby/blob/master/doc/contributing/building_ruby.md, you can successfully build Ruby with ASAN enabled, however, the test suite has several failures. I'm currently working on addressing these: The next step is to merge https://github.com/ruby/ruby/pull/10122 (https://bugs.ruby-lang.org/issues/20310) which I plan to do next week (I'm currently away on a work trip). That makes sure that VALUEs stored in ASAN fake stacks from threads other than the currently running thread get marked during GC. After that, I need to push up patches for the remaining few issues. I mostly have these patches ready to go already; in fact, last week I got the full `make check` suite passing all tests with ASAN enabled! Once that's working, I'd like to investigate how ASAN can fit into CRuby's CI matrix somewhere so that it _stays_ working, although I have not thought too deeply about this yet. I will provide further updates on this ticket so anybody interested can stay in the loop. -- https://bugs.ruby-lang.org/