From 86827bc42b4aa72a240672cea6836949879c7dfa Mon Sep 17 00:00:00 2001 From: sinkingpoint Date: Wed, 7 Feb 2024 09:00:42 +1100 Subject: [PATCH] Nil check named pipe shutdowns When the `Start` method of the named pipe is called, it will create a new named pipe and start listening for connections. If that Start method _fails_ for any reason, some parts of the named pipe will not be initialized. This means that when the `Stop` method is called (as the collector does when `Start` fails), it will panic with a nil pointer dereference. This change adds a couple of nil checks to the `Stop` method to prevent this panic, because otherwise we just get the SIGSEGV signal, and we never get any error logs. Signed-off-by: sinkingpoint --- .chloggen/sinkingpoint_named-pipe-sigsev.yaml | 27 +++++++++++++++++++ .../operator/input/namedpipe/namedpipe.go | 10 +++++-- 2 files changed, 35 insertions(+), 2 deletions(-) create mode 100755 .chloggen/sinkingpoint_named-pipe-sigsev.yaml diff --git a/.chloggen/sinkingpoint_named-pipe-sigsev.yaml b/.chloggen/sinkingpoint_named-pipe-sigsev.yaml new file mode 100755 index 0000000000000..26f2a52ac98ef --- /dev/null +++ b/.chloggen/sinkingpoint_named-pipe-sigsev.yaml @@ -0,0 +1,27 @@ +# Use this changelog template to create an entry for release notes. + +# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix' +change_type: bug_fix + +# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver) +component: namedpipereceiver + +# A brief description of the change. Surround your text with quotes ("") if it needs to start with a backtick (`). +note: Fix SIGSEGV when named pipe creation fails + +# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists. +issues: [31088] + +# (Optional) One or more lines of additional information to render under the primary note. +# These lines will be padded with 2 spaces and then inserted directly into the document. +# Use pipe (|) for multiline entries. +subtext: + +# If your change doesn't affect end users or the exported elements of any package, +# you should instead start your pull request title with [chore] or use the "Skip Changelog" label. +# Optional: The change log or logs in which this entry should be included. +# e.g. '[user]' or '[user, api]' +# Include 'user' if the change is relevant to end users. +# Include 'api' if there is a change to a library API. +# Default: '[user]' +change_logs: [] diff --git a/pkg/stanza/operator/input/namedpipe/namedpipe.go b/pkg/stanza/operator/input/namedpipe/namedpipe.go index a4ab7850dde44..533eef7d9c385 100644 --- a/pkg/stanza/operator/input/namedpipe/namedpipe.go +++ b/pkg/stanza/operator/input/namedpipe/namedpipe.go @@ -134,8 +134,14 @@ func (n *Input) Start(_ operator.Persister) error { } func (n *Input) Stop() error { - n.pipe.Close() - n.cancel() + if n.pipe != nil { + n.pipe.Close() + } + + if n.cancel != nil { + n.cancel() + } + n.wg.Wait() return nil }