Avoid potential deadlock in getaddrinfo #848
Open
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
Test failed to create a sender thread due to a name clash between sender the thread and the sender callback parameter. Sender thread produces lots of expected errors (of "Connection refused" kind), so we also silence errors from the client library.
time.sleep(0) allows python to switch to another thread, allowing main thread to progress through stages quicker, while still being able to catch deadlocks from getaddrinfo or improper locking in fork hooks.
Try sending metric from the child process. This makes sure that all locks are still in a serviceable state after the fork.
getaddrinfo may use an internal lock that, in case of a concurrent fork, may be left in locked state and cause child process to deadlock.
vickenty
added
the
changelog/Fixed
pre_fork is now mutually exclusive with get_socket() until post_fork is called, so the sequence of events that the test was testing is no longer possible.
carlosroman
previously approved these changes
Aug 23, 2024
|
This issue has been automatically marked as stale because it has not had activity in the last 30 days. |
|
This issue has been automatically marked as stale because it has not had activity in the last 30 days. |
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Outdated suggestions cannot be applied.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.
What does this PR do?
Avoid deadlock in the child process in getaddrinfo if the application forks while a thread is trying to create a socket.
Description of the Change
Acquire socket lock before forking to prevent the client library from calling getaddrinfo at the same time.
Alternate Designs
Possible Drawbacks
Verification Process
Additional Notes
Release Notes
Review checklist (to be filled by reviewers)
changelog/label attached. If applicable it should have thebackward-incompatiblelabel attached.do-not-merge/label attached.kind/andseverity/labels attached at least.