Deny modifications of "invisible" deleted files

Author: vitalif

README.md

@@ -51,6 +51,8 @@ List of non-POSIX behaviors/limitations for GeeseFS:
   - file modification time can't be set by user (for example with `cp --preserve`, `rsync -a` or utimes(2))
 * Does not support hard links
 * Does not support locking
+* Does not support "invisible" deleted files. If an app keeps an opened file descriptor
+  after deleting the file it will get ENOENT errors from FS operations
 
 In addition to the items above:
 * Default file size limit is 1.03 TB, achieved by splitting the file into 1000x 5MB parts,

internal/dir.go

@@ -685,7 +685,7 @@ func (dh *DirHandle) ReadDir(internalOffset int, offset fuseops.DirOffset) (en *
 		childTmp := parent.dir.Children[i]
 		if childTmp.AttrTime.Before(parent.dir.refreshStartTime) &&
 			atomic.LoadInt32(&childTmp.fileHandles) == 0 &&
-			atomic.LoadInt32(&childTmp.CacheState) == ST_CACHED &&
+			atomic.LoadInt32(&childTmp.CacheState) <= ST_DEAD &&
 			(!childTmp.isDir() || atomic.LoadInt64(&childTmp.dir.ModifiedChildren) == 0) {
 			childTmp.mu.Lock()
 			notifications = append(notifications, &fuseops.NotifyDelete{
@@ -1043,7 +1043,7 @@ func (inode *Inode) SendDelete() {
 		}
 		forget := false
 		if inode.CacheState == ST_DELETED {
-			inode.SetCacheState(ST_CACHED)
+			inode.SetCacheState(ST_DEAD)
 			// We don't remove directories until all children are deleted
 			// So that we don't revive the directory after removing it
 			// by fetching a list of files not all of which are actually deleted
@@ -1313,14 +1313,21 @@ func (inode *Inode) doUnlink() {
 	} else if inode.CacheState != ST_CREATED || inode.IsFlushing > 0 {
 		// resetCache will clear all buffers and abort the multipart upload
 		inode.resetCache()
-		inode.SetCacheState(ST_DELETED)
-		if parent.dir.DeletedChildren == nil {
-			parent.dir.DeletedChildren = make(map[string]*Inode)
+		if parent.dir.DeletedChildren == nil || parent.dir.DeletedChildren[inode.Name] == nil {
+			inode.SetCacheState(ST_DELETED)
+			if parent.dir.DeletedChildren == nil {
+				parent.dir.DeletedChildren = make(map[string]*Inode)
+			}
+			parent.dir.DeletedChildren[inode.Name] = inode
+		} else {
+			// A deleted file is already present, we can just reset the cache
+			inode.SetCacheState(ST_DEAD)
 		}
-		parent.dir.DeletedChildren[inode.Name] = inode
 	} else {
 		inode.resetCache()
+		inode.SetCacheState(ST_DEAD)
 	}
+	inode.Attributes.Size = 0
 
 	parent.removeChildUnlocked(inode)
 }
@@ -1522,7 +1529,9 @@ func renameInCache(fromInode *Inode, newParent *Inode, to string) {
 			if parent.dir.DeletedChildren == nil {
 				parent.dir.DeletedChildren = make(map[string]*Inode)
 			}
-			parent.dir.DeletedChildren[fromInode.Name] = fromInode
+			if parent.dir.DeletedChildren[fromInode.Name] == nil {
+				parent.dir.DeletedChildren[fromInode.Name] = fromInode
+			}
 			fromInode.renamingTo = false
 		} else {
 			parent.addModified(-1)
@@ -1538,7 +1547,9 @@ func renameInCache(fromInode *Inode, newParent *Inode, to string) {
 		if parent.dir.DeletedChildren == nil {
 			parent.dir.DeletedChildren = make(map[string]*Inode)
 		}
-		parent.dir.DeletedChildren[fromInode.Name] = fromInode
+		if parent.dir.DeletedChildren[fromInode.Name] == nil {
+			parent.dir.DeletedChildren[fromInode.Name] = fromInode
+		}
 		if fromInode.CacheState == ST_CACHED {
 			// Was not modified and we remove it from current parent => add modified
 			parent.addModified(1)
@@ -1637,7 +1648,7 @@ func (parent *Inode) insertSubTree(path string, obj *BlobItemOutput, dirs map[*I
 			}
 		} else if !inode.isDir() {
 			// replace unmodified file item with a directory
-			if atomic.LoadInt32(&inode.CacheState) == ST_CACHED {
+			if atomic.LoadInt32(&inode.CacheState) <= ST_DEAD {
 				inode.mu.Lock()
 				atomic.StoreInt32(&inode.refreshed, -1)
 				parent.removeChildUnlocked(inode)

internal/file.go

@@ -457,6 +457,13 @@ func (fh *FileHandle) WriteFile(offset int64, data []byte, copyData bool) (err e
 
 	fh.inode.mu.Lock()
 
+	if fh.inode.CacheState == ST_DELETED || fh.inode.CacheState == ST_DEAD {
+		// Oops, it's a deleted file. We don't support changing invisible files
+		fh.inode.fs.bufferPool.Use(-int64(len(data)), false)
+		fh.inode.mu.Unlock()
+		return fuse.ENOENT
+	}
+
 	fh.inode.checkPauseWriters()
 
 	if fh.inode.Attributes.Size < end {
@@ -1161,7 +1168,7 @@ func (fh *FileHandle) Release() {
 	if n == -1 {
 		panic(fmt.Sprintf("Released more file handles than acquired, n = %v", n))
 	}
-	if n == 0 && atomic.LoadInt32(&fh.inode.CacheState) == ST_CACHED {
+	if n == 0 && atomic.LoadInt32(&fh.inode.CacheState) <= ST_DEAD {
 		fh.inode.Parent.addModified(-1)
 	}
 	fh.inode.fs.WakeupFlusher()
@@ -2085,7 +2092,7 @@ func (inode *Inode) SyncFile() (err error) {
 	for {
 		inode.mu.Lock()
 		inode.forceFlush = false
-		if inode.CacheState == ST_CACHED {
+		if inode.CacheState <= ST_DEAD {
 			inode.mu.Unlock()
 			break
 		}

internal/goofys.go

@@ -1733,6 +1733,11 @@ func (fs *Goofys) SetInodeAttributes(
 
 	if op.Size != nil || op.Mode != nil || op.Mtime != nil || op.Uid != nil || op.Gid != nil {
 		inode.mu.Lock()
+		if inode.CacheState == ST_DELETED || inode.CacheState == ST_DEAD {
+			// Oops, it's a deleted file. We don't support changing invisible files
+			inode.mu.Unlock()
+			return fuse.ENOENT
+		}
 	}
 
 	modified := false

internal/handles.go

@@ -38,9 +38,10 @@ import (
 
 const (
 	ST_CACHED int32 = 0
-	ST_CREATED int32 = 1
-	ST_MODIFIED int32 = 2
-	ST_DELETED int32 = 3
+	ST_DEAD int32 = 1
+	ST_CREATED int32 = 2
+	ST_MODIFIED int32 = 3
+	ST_DELETED int32 = 4
 )
 
 type InodeAttributes struct {
@@ -611,6 +612,11 @@ func (inode *Inode) SetXattr(name string, value []byte, flags uint32) error {
 	inode.mu.Lock()
 	defer inode.mu.Unlock()
 
+	if inode.CacheState == ST_DELETED || inode.CacheState == ST_DEAD {
+		// Oops, it's a deleted file. We don't support changing invisible files
+		return fuse.ENOENT
+	}
+
 	meta, name, err := inode.getXattrMap(name, true)
 	if err != nil {
 		return err
@@ -644,6 +650,11 @@ func (inode *Inode) RemoveXattr(name string) error {
 	inode.mu.Lock()
 	defer inode.mu.Unlock()
 
+	if inode.CacheState == ST_DELETED || inode.CacheState == ST_DEAD {
+		// Oops, it's a deleted file. We don't support changing invisible files
+		return fuse.ENOENT
+	}
+
 	meta, name, err := inode.getXattrMap(name, true)
 	if err != nil {
 		return err