Rollup of 5 pull requests #97107
Closed
Rollup of 5 pull requests #97107
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
Issue rust-lang#84096 changed the hashmap RNG to use BCryptGenRandom instead of RtlGenRandom on Windows. Mozilla Firefox started experiencing random failures in env_logger::Builder::new() (Issue rust-lang#94098) during initialization of their unsandboxed main process with an "Access Denied" error message from BCryptGenRandom(), which is used by the HashMap contained in env_logger::Builder The root cause appears to be a virus scanner or other software interfering with BCrypt DLLs loading. This change adds a fallback option if BCryptGenRandom is unusable for whatever reason. It will fallback to RtlGenRandom in this case. Fixes rust-lang#94098
Add a couple tests for rust-lang#90887 fixes closes rust-lang#56556 closes rust-lang#90875 These are confirmed fixes by rust-lang#90887, so r? `@jackh726`
Make HashMap fall back to RtlGenRandom if BCryptGenRandom fails With PR rust-lang#84096, Rust `std::collections::hash_map::RandomState` changed from using `RtlGenRandom()` ([msdn](https://docs.microsoft.com/en-us/windows/win32/api/ntsecapi/nf-ntsecapi-rtlgenrandom)) to `BCryptGenRandom()` ([msdn](https://docs.microsoft.com/en-us/windows/win32/api/bcrypt/nf-bcrypt-bcryptgenrandom)) as its source of secure randomness after much discussion ([here](rust-random/getrandom#65 (comment)), among other places). Unfortunately, after that PR landed, Mozilla Firefox started experiencing fairly-rare crashes during startup while attempting to initialize the `env_logger` crate. ([docs for env_logger](https://docs.rs/env_logger/latest/env_logger/)) The root issue is that on some machines, `BCryptGenRandom()` will fail with an `Access is denied. (os error 5)` error message. ([Bugzilla issue 1754490](https://bugzilla.mozilla.org/show_bug.cgi?id=1754490)) (Discussion in issue rust-lang#94098) Note that this is happening upon startup of Firefox's unsandboxed Main Process, so this behavior is different and separate from previous issues ([like this](https://bugzilla.mozilla.org/show_bug.cgi?id=1746254)) where BCrypt DLLs were blocked by process sandboxing. In the case of sandboxing, we knew we were doing something abnormal and expected that we'd have to resort to abnormal measures to make it work. However, in this case we are in a regular unsandboxed process just trying to initialize `env_logger` and getting a panic. We suspect that this may be caused by a virus scanner or some other security software blocking the loading of the BCrypt DLLs, but we're not completely sure as we haven't been able to replicate locally. It is also possible that Firefox is not the only software affected by this; we just may be one of the pieces of Rust software that has the telemetry and crash reporting necessary to catch it. I have read some of the historical discussion around using `BCryptGenRandom()` in Rust code, and I respect the decision that was made and agree that it was a good course of action, so I'm not trying to open a discussion about a return to `RtlGenRandom()`. Instead, I'd like to suggest that perhaps we use `RtlGenRandom()` as a "fallback RNG" in the case that BCrypt doesn't work. This pull request implements this fallback behavior. I believe this would improve the robustness of this essential data structure within the standard library, and I see only 2 potential drawbacks: 1. Slight added overhead: It should be quite minimal though. The first call to `sys::rand::hashmap_random_keys()` will incur a bit of initialization overhead, and every call after will incur roughly 2 non-atomic global reads and 2 easily predictable branches. Both should be negligible compared to the actual cost of generating secure random numbers 2. `RtlGenRandom()` is deprecated by Microsoft: Technically true, but as mentioned in [this comment on GoLang](golang/go#33542 (comment)), this API is ubiquitous in Windows software and actually removing it would break lots of things. Also, Firefox uses it already in [our C++ code](https://searchfox.org/mozilla-central/rev/5f88c1d6977e03e22d3420d0cdf8ad0113c2eb31/mfbt/RandomNum.cpp#25), and [Chromium uses it in their code as well](https://source.chromium.org/chromium/chromium/src/+/main:base/rand_util_win.cc) (which transitively means that Microsoft uses it in their own web browser, Edge). If there did come a time when Microsoft truly removes this API, it should be easy enough for Rust to simply remove the fallback in the code I've added here
…rrors Add regression test for rust-lang#81804 Closes rust-lang#81804 r? `@compiler-errors`
Change `Successors` to `impl Iterator<Item = BasicBlock>` This PR fixes the FIXME in `compiler\rustc_middle\src\mir\mod.rs`. This can omit several `&`, `*` or `cloned` operations on Successros' generated elements
remove the `RelateResultCompare` trait it's unused
rustbot
added
T-compiler
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.
Successful merges:
Successorstoimpl Iterator<Item = BasicBlock>#97079 (ChangeSuccessorstoimpl Iterator<Item = BasicBlock>)RelateResultComparetrait #97080 (remove theRelateResultComparetrait)Failed merges:
r? @ghost
@rustbot modify labels: rollup
Create a similar rollup