vfs: fix deadlock under concurrent truncate and releases (#3457)

juicedata · Apr 10, 2023 · 20630b8 · 20630b8
1 parent 5244ced
commit 20630b8
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Showing 2 changed files with 10 additions and 1 deletion.
diff --git a/pkg/vfs/handle.go b/pkg/vfs/handle.go
@@ -166,7 +166,14 @@ func (v *VFS) newHandle(inode Ino) *handle {
 func (v *VFS) findAllHandles(inode Ino) []*handle {
 	v.hanleM.Lock()
 	defer v.hanleM.Unlock()
-	return v.handles[inode]
+	hs := v.handles[inode]
+	if len(hs) <= 1 {
+		return hs
+	}
+	// copy hs so it will not be modified by releaseHandle
+	hs2 := make([]*handle, len(hs))
+	copy(hs2, hs)
+	return hs2
 }
 
 func (v *VFS) findHandle(inode Ino, fh uint64) *handle {

diff --git a/pkg/vfs/vfs.go b/pkg/vfs/vfs.go
@@ -19,6 +19,7 @@ package vfs
 import (
 	"encoding/json"
 	"runtime"
+	"sort"
 	"sync"
 	"syscall"
 	"time"
@@ -438,6 +439,7 @@ func (v *VFS) Truncate(ctx Context, ino Ino, size int64, opened uint8, attr *Att
 		return
 	}
 	hs := v.findAllHandles(ino)
+	sort.Slice(hs, func(i, j int) bool { return hs[i].fh < hs[j].fh })
 	for _, h := range hs {
 		if !h.Wlock(ctx) {
 			err = syscall.EINTR