fluencelabs/tendermint
1
0
Fork 0
mirror of https://github.com/fluencelabs/tendermint synced 2025-06-12 21:01:21 +00:00
Code Issues Projects Releases Wiki Activity

rpc: protect subscription access from race condition (#3910)

Browse Source 
When using the RPC client in my test suite (with -race enabled), I do a lot of Subscribe/Unsubscribe operations, at some point (randomly) the race detector returns the following warning:

WARNING: DATA RACE
Read at 0x00c0009dbe30 by goroutine 31:
runtime.mapiterinit()
/usr/local/go/src/runtime/map.go:804 +0x0
github.com/tendermint/tendermint/rpc/client.(*WSEvents).redoSubscriptionsAfter()
/go/pkg/mod/github.com/tendermint/tendermint@v0.31.5/rpc/client/httpclient.go:364 +0xc0
github.com/tendermint/tendermint/rpc/client.(*WSEvents).eventListener()
/go/pkg/mod/github.com/tendermint/tendermint@v0.31.5/rpc/client/httpclient.go:393 +0x3c6 

Turns out that the redoSubscriptionAfter is not protecting the access to subscriptions.

The following change protects the read access to the subscription map behind the mutex
This commit is contained in:
Gustavo Chaín
2019-08-22 11:23:07 +02:00
committed by Anton Kaliaev
parent eec6d33e14
commit 7b2d018f84
2 changed files with 3 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
rpc/client/httpclient.go
View File

@ -453,6 +453,8 @@ func (w *WSEvents) UnsubscribeAll(ctx context.Context, subscriber string) error
func (w *WSEvents) redoSubscriptionsAfter(d time.Duration) {
time.Sleep(d)
w.mtx.RLock()
defer w.mtx.RUnlock()
for q := range w.subscriptions {
err := w.ws.Subscribe(context.Background(), q)
if err != nil {