From ef8476bd27b3de319199b8f330f4a484978241cc Mon Sep 17 00:00:00 2001
From: Sandy Xu <sandy@juicedata.io>
Date: Wed, 30 Mar 2022 18:00:50 +0800
Subject: [PATCH 1/2] meta: forbid empty name for dentry

---
 pkg/meta/base.go | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/pkg/meta/base.go b/pkg/meta/base.go
index 79650d9ca45d..663fc43fa91e 100644
--- a/pkg/meta/base.go
+++ b/pkg/meta/base.go
@@ -591,6 +591,9 @@ func (m *baseMeta) Mknod(ctx Context, parent Ino, name string, _type uint8, mode
 	if m.conf.ReadOnly {
 		return syscall.EROFS
 	}
+	if name == "" {
+		return syscall.ENOENT
+	}
 
 	defer timeit(time.Now())
 	if m.checkQuota(4<<10, 1) {
@@ -631,6 +634,9 @@ func (m *baseMeta) Link(ctx Context, inode, parent Ino, name string, attr *Attr)
 	if m.conf.ReadOnly {
 		return syscall.EROFS
 	}
+	if name == "" {
+		return syscall.ENOENT
+	}
 
 	defer timeit(time.Now())
 	parent = m.checkRoot(parent)
@@ -696,6 +702,9 @@ func (m *baseMeta) Rename(ctx Context, parentSrc Ino, nameSrc string, parentDst
 	if m.conf.ReadOnly {
 		return syscall.EROFS
 	}
+	if nameDst == "" {
+		return syscall.ENOENT
+	}
 	switch flags {
 	case 0, RenameNoReplace, RenameExchange:
 	case RenameWhiteout, RenameNoReplace | RenameWhiteout:

From 9e5d18000a73d20df168cd57ee74201b6b66acf1 Mon Sep 17 00:00:00 2001
From: Sandy Xu <sandy@juicedata.io>
Date: Wed, 30 Mar 2022 21:14:41 +0800
Subject: [PATCH 2/2] meta: readdir skips entry with empty name

---
 pkg/meta/redis.go | 8 ++++++--
 pkg/meta/sql.go   | 4 ++++
 pkg/meta/tkv.go   | 8 ++++++--
 3 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/pkg/meta/redis.go b/pkg/meta/redis.go
index fe8893462ca4..9bf140da019e 100644
--- a/pkg/meta/redis.go
+++ b/pkg/meta/redis.go
@@ -1577,9 +1577,13 @@ func (r *redisMeta) doReaddir(ctx Context, inode Ino, plus uint8, entries *[]*En
 		newEntries := make([]Entry, len(keys)/2)
 		newAttrs := make([]Attr, len(keys)/2)
 		for i := 0; i < len(keys); i += 2 {
-			typ, inode := r.parseEntry([]byte(keys[i+1]))
+			typ, ino := r.parseEntry([]byte(keys[i+1]))
+			if keys[i] == "" {
+				logger.Errorf("Corrupt entry with empty name: inode %d parent %d", ino, inode)
+				continue
+			}
 			ent := &newEntries[i/2]
-			ent.Inode = inode
+			ent.Inode = ino
 			ent.Name = []byte(keys[i])
 			ent.Attr = &newAttrs[i/2]
 			ent.Attr.Typ = typ
diff --git a/pkg/meta/sql.go b/pkg/meta/sql.go
index 30b2dbf84367..d1523504945f 100644
--- a/pkg/meta/sql.go
+++ b/pkg/meta/sql.go
@@ -1589,6 +1589,10 @@ func (m *dbMeta) doReaddir(ctx Context, inode Ino, plus uint8, entries *[]*Entry
 		return errno(err)
 	}
 	for _, n := range nodes {
+		if n.Name == "" {
+			logger.Errorf("Corrupt entry with empty name: inode %d parent %d", n.Inode, inode)
+			continue
+		}
 		entry := &Entry{
 			Inode: n.Inode,
 			Name:  []byte(n.Name),
diff --git a/pkg/meta/tkv.go b/pkg/meta/tkv.go
index 0bd1a6551ae0..f9d1d3a1a781 100644
--- a/pkg/meta/tkv.go
+++ b/pkg/meta/tkv.go
@@ -1426,9 +1426,13 @@ func (m *kvMeta) doReaddir(ctx Context, inode Ino, plus uint8, entries *[]*Entry
 	}
 	prefix := len(m.entryKey(inode, ""))
 	for name, buf := range vals {
-		typ, inode := m.parseEntry(buf)
+		typ, ino := m.parseEntry(buf)
+		if len(name) == prefix {
+			logger.Errorf("Corrupt entry with empty name: inode %d parent %d", ino, inode)
+			continue
+		}
 		*entries = append(*entries, &Entry{
-			Inode: inode,
+			Inode: ino,
 			Name:  []byte(name)[prefix:],
 			Attr:  &Attr{Typ: typ},
 		})