MyFavMirrors/minio
1
0
Fork 0
mirror of https://github.com/minio/minio.git synced 2025-01-11 15:03:22 -05:00
Code Issues Packages Projects Releases Wiki Activity

Fix panic on double unfreezeServices (#18177)

Browse Source 
Calling unfreezeServices twice results in panic:

```
panic: "POST /minio/peer/v32/signalservice?signal=4&sub-sys=": close of nil channel
goroutine 14703 [running]:
runtime/debug.Stack()
	runtime/debug/stack.go:24 +0x65
github.com/minio/minio/cmd.setCriticalErrorHandler.func1.1()
	github.com/minio/minio/cmd/generic-handlers.go:549 +0x8e
panic({0x27c3020, 0x4c9b370})
	runtime/panic.go:884 +0x212
github.com/minio/minio/cmd.unfreezeServices()
	github.com/minio/minio/cmd/service.go:112 +0xc7
github.com/minio/minio/cmd.(*peerRESTServer).SignalServiceHandler(0x0?, {0x4cb6af0, 0xc010b96420}, 0xc01affab00)
	github.com/minio/minio/cmd/peer-rest-server.go:837 +0x13a
net/http.HandlerFunc.ServeHTTP(...)
```

If the function was called a second time `val` would not be nil, but the returned channel `ch` would be, causing the panic.

Check the channel isn't nil and also use Swap for an atomic swap instead of 2 separate operations (though we are in a mutex).
This commit is contained in:
Klaus Post 2023-10-06 06:51:50 -07:00 committed by GitHub
parent 9dc29d7687
commit 0de2b9a1b2
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 5 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
cmd/service.go
View File

@ -104,11 +104,11 @@ func unfreezeServices() {
// Close when we reach 0
globalServiceFreezeCnt--
if globalServiceFreezeCnt <= 0 {
// Ensure we only close once.
if val := globalServiceFreeze.Load(); val != nil {
var _ch chan struct{}
if ch, ok := val.(chan struct{}); ok {
globalServiceFreeze.Store(_ch)
// Set to a nil channel.
var _ch chan struct{}
if val := globalServiceFreeze.Swap(_ch); val != nil {
if ch, ok := val.(chan struct{}); ok && ch != nil {
// Close previous non-nil channel.
close(ch)
}
}