github/weave-scope
1
0
Fork 0
mirror of https://github.com/weaveworks/scope.git synced 2026-02-14 18:09:59 +00:00
Code Issues Packages Projects Releases Wiki Activity

fix: copy report before modifying

Browse Source 
We call `UnsafeRemovePartMergedNodes()` which modifies the data,
so all implementations of Report() must ensure they return a new object,
not one which is cached or shared across goroutines.
This commit is contained in:
Bryan Boreham
2021-05-17 17:31:37 +00:00
parent c36b339bfc
commit f4bc57b1fc
1 changed files with 5 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

9
app/collector.go
View File

@@ -28,7 +28,7 @@ const reportQuantisationInterval = 3 * time.Second
// Reporter is something that can produce reports on demand. It's a convenient
// interface for parts of the app, and several experimental components.
type Reporter interface {
Report(context.Context, time.Time) (report.Report, error)
Report(context.Context, time.Time) (report.Report, error) // must return an object that is OK to modify
HasReports(context.Context, time.Time) (bool, error)
HasHistoricReports() bool
AdminSummary(context.Context, time.Time) (string, error)
@@ -133,6 +133,7 @@ func (c *collector) Add(_ context.Context, rpt report.Report, _ []byte) error {
// Report returns a merged report over all added reports. It implements
// Reporter.
// Note we copy return a copy in case callers modify the data.
func (c *collector) Report(_ context.Context, timestamp time.Time) (report.Report, error) {
c.mtx.Lock()
defer c.mtx.Unlock()
@@ -142,7 +143,7 @@ func (c *collector) Report(_ context.Context, timestamp time.Time) (report.Repor
if c.cached != nil && len(c.reports) > 0 {
oldest := timestamp.Add(-c.window)
if c.timestamps[0].After(oldest) {
return *c.cached, nil
return c.cached.Copy(), nil
}
}
@@ -155,7 +156,7 @@ func (c *collector) Report(_ context.Context, timestamp time.Time) (report.Repor
rpt := c.merger.Merge(c.reports)
c.cached = &rpt
return rpt, nil
return rpt.Copy(), nil
}
// HasReports indicates whether the collector contains reports between
@@ -244,7 +245,7 @@ type StaticCollector report.Report
// Report returns a merged report over all added reports. It implements
// Reporter.
func (c StaticCollector) Report(context.Context, time.Time) (report.Report, error) {
return report.Report(c), nil
return report.Report(c).Copy(), nil
}
// Close is a no-op for the static collector