filesystem: Fix crash when watch callback returns error or throws#42554
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botengyao merged 4 commits intoenvoyproxy:mainfrom Dec 16, 2025
Merged
filesystem: Fix crash when watch callback returns error or throws#42554botengyao merged 4 commits intoenvoyproxy:mainfrom
botengyao merged 4 commits intoenvoyproxy:mainfrom
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Previously, when a filesystem watch callback returned a non-OK status or threw an exception, the error would propagate to FileEventImpl which uses THROW_IF_NOT_OK. Since there's no exception handler in the libevent loop, this caused std::terminate to be called, crashing Envoy. This change makes the inotify (Linux) and kqueue (macOS) watchers handle callback errors gracefully by: 1. Catching exceptions using TRY_ASSERT_MAIN_THREAD/MULTI_CATCH macros. 2. Logging errors at WARN level instead of propagating them. 3. Always returning OkStatus to the event loop. This improves resilience during config/secret hot reloads where transient errors should not crash the proxy. Risk Level: Medium Testing: Added unit tests for error status and exception handling paths. Signed-off-by: Rohit Agrawal <rohit.agrawal@salesforce.com> Signed-off-by: Rohit Agrawal <rohit.agrawal@databricks.com>
botengyao
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Dec 15, 2025
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sorry for the delay, lgtm module the log spam part.
/wait
| absl::StatusOr<PathSplitResult> pathname_or_error = | ||
| file_system_.splitPathFromFilename(file->file_); | ||
| RETURN_IF_NOT_OK_REF(pathname_or_error.status()); | ||
| if (!pathname_or_error.ok()) { |
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A pathname failure is not temporary, will continuing mean you may warn forever on every event and never recover?
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Hmmm, I think a better fix here would be to remove the broken watch.
Signed-off-by: Rohit Agrawal <rohit.agrawal@databricks.com>
Signed-off-by: Rohit Agrawal <rohit.agrawal@databricks.com>
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Description
Today, when a filesystem watch callback returns a non-OK status or throws an exception, the error gets propagated to
FileEventImplwhich usesTHROW_IF_NOT_OK.Since there's no exception handler in the
libeventloop, this causesstd::terminateto be called, which crashes Envoy.Stack Trace:
In this change, we are making the
inotifyandkqueuewatchers handle callback errors gracefully by catching any exceptions usingTRY_ASSERT_MAIN_THREAD, logging errors instead of propagating them and always returning theOkStatusto the event loop.Commit Message: filesystem: Fix crash when watch callback returns error or throws
Additional Description: Make
inotifyandkqueuewatchers handle callback errors gracefully.Risk Level: Low
Testing: CI
Docs Changes: N/A
Release Notes: N/A