diff --git a/qtfs/qtfs/proc.c b/qtfs/qtfs/proc.c
index 8077653192952227585ead0359268a74b0a11477..cc90cd3f6644e1ac94da6589272dfdc0556943f9 100644
--- a/qtfs/qtfs/proc.c
+++ b/qtfs/qtfs/proc.c
@@ -130,7 +130,7 @@ struct dentry *qtfs_proc_lookup(struct inode *parent_inode, struct dentry *child
 	memset(cpath, 0, MAX_PATH_LEN);
 	memset(tmp, 0, MAX_PATH_LEN);
 
-	if (qtfs_fullname(cpath, child_dentry) < 0) {
+	if (qtfs_fullname(cpath, child_dentry, MAX_PATH_LEN) < 0) {
 		qtfs_err("%s: failed to get fullname", __func__);
 		goto remote;
 	}
@@ -193,7 +193,7 @@ const char *qtfs_proc_getlink(struct dentry *dentry,
 	memset(path, 0, MAX_PATH_LEN);
 	memset(tmp, 0, MAX_PATH_LEN);
 
-	if (qtfs_fullname(path, dentry) < 0) {
+	if (qtfs_fullname(path, dentry, MAX_PATH_LEN) < 0) {
 		qtfs_info("[%s]: get path failed", __func__);
 		goto link_remote;
 	}
@@ -254,7 +254,7 @@ int qtfs_proc_getattr(const struct path *path, struct kstat *stat, u32 req_mask,
 	memset(tmp, 0, MAX_PATH_LEN);
 	memset(local_path, 0, MAX_PATH_LEN);
 
-	if (qtfs_fullname(cpath, path->dentry) < 0) {
+	if (qtfs_fullname(cpath, path->dentry, MAX_PATH_LEN) < 0) {
 		qtfs_err("%s: failed to get fullname", __func__);
 		goto remote;
 	}
diff --git a/qtfs/qtfs/qtfs-mod.h b/qtfs/qtfs/qtfs-mod.h
index 6be61fa060206e0a5a3bc24ed7c664f5e405ae70..ed37c6ef7b63c973462d5e8ad3aca6497ec1b7f2 100644
--- a/qtfs/qtfs/qtfs-mod.h
+++ b/qtfs/qtfs/qtfs-mod.h
@@ -111,7 +111,7 @@ struct qtmiss_ops {
 	char str[32];
 };
 
-static inline int qtfs_fullname(char *fullname, struct dentry *d)
+static inline int qtfs_fullname(char *fullname, struct dentry *d, size_t buflen)
 {
 	struct qtfs_fs_info *fsinfo = NULL;
 	int len = 0;
@@ -122,6 +122,11 @@ static inline int qtfs_fullname(char *fullname, struct dentry *d)
 		qtfs_info("%s: get dentry fullname NULL\n", __func__);
 		return -1;
 	}
+	if (buflen < MAX_PATH_LEN) {
+		qtfs_err("%s: failed to get fullname dure to small buflen:%d\n", __func__, buflen);
+		return -1;
+	}
+	
 	name = __getname();
 	if (!name) {
 		return -1;
@@ -158,8 +163,8 @@ static inline int qtfs_fullname(char *fullname, struct dentry *d)
 	return len;
 }
 
-#define QTFS_FULLNAME(fullname, d) \
-	if (qtfs_fullname(fullname, d)<0) { \
+#define QTFS_FULLNAME(fullname, d, buflen) \
+	if (qtfs_fullname(fullname, d, buflen)<0) { \
 		qtfs_err("qtfs fullname failed\n"); \
 		qtfs_conn_put_param(pvar); \
 		return -EINVAL; \
diff --git a/qtfs/qtfs/sb.c b/qtfs/qtfs/sb.c
index 44389f4c7c187855e5ec6ff47795c495808a9ee5..a48f5d31ab7a031acecf98838885cf771b1a20b8 100644
--- a/qtfs/qtfs/sb.c
+++ b/qtfs/qtfs/sb.c
@@ -47,7 +47,7 @@ int qtfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 	req = pvar->conn_ops->get_conn_msg_buf(pvar, QTFS_SEND);
 	rsp = pvar->conn_ops->get_conn_msg_buf(pvar, QTFS_RECV);
 
-	QTFS_FULLNAME(req->path, dentry);
+	QTFS_FULLNAME(req->path, dentry, sizeof(req->path));
 	rsp = qtfs_remote_run(pvar, QTFS_REQ_STATFS, QTFS_SEND_SIZE(struct qtreq_statfs, req->path));
 	if (IS_ERR_OR_NULL(rsp)) {
 		qtfs_conn_put_param(pvar);
@@ -139,7 +139,7 @@ int qtfs_readdir(struct file *filp, struct dir_context *ctx)
 
 	req = pvar->conn_ops->get_conn_msg_buf(pvar, QTFS_SEND);
 	rsp = pvar->conn_ops->get_conn_msg_buf(pvar, QTFS_RECV);
-	QTFS_FULLNAME(req->path, filp->f_path.dentry);
+	QTFS_FULLNAME(req->path, filp->f_path.dentry, sizeof(req->path));
 	req->count = sizeof(rsp->dirent);
 	req->pos = ctx->pos;
 
@@ -196,7 +196,7 @@ int qtfs_open(struct inode *inode, struct file *file)
 	}
 
 	req = pvar->conn_ops->get_conn_msg_buf(pvar, QTFS_SEND);
-	QTFS_FULLNAME(req->path, file->f_path.dentry);
+	QTFS_FULLNAME(req->path, file->f_path.dentry, sizeof(req->path));
 
 	req->flags = file->f_flags;
 	req->mode = file->f_mode;
@@ -620,7 +620,7 @@ long qtfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 			if (!fullname)
 				return -ENOMEM;
 			memset(fullname, 0, MAX_PATH_LEN);
-			qtfs_fullname(fullname, filp->f_path.dentry);
+			qtfs_fullname(fullname, filp->f_path.dentry, MAX_PATH_LEN);
 			qtfs_err("qtfs ioctl get not support cmd:%d file:%s TCGETS:%d", cmd, fullname, TCGETS);
 			kfree(fullname);
 			return -EOPNOTSUPP;
@@ -862,7 +862,7 @@ int qtfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 	}
 
 	req = pvar->conn_ops->get_conn_msg_buf(pvar, QTFS_SEND);
-	QTFS_FULLNAME(req->path, dentry);
+	QTFS_FULLNAME(req->path, dentry, sizeof(req->path));
 
 	req->mode = mode;
 	rsp = qtfs_remote_run(pvar, QTFS_REQ_MKDIR, QTFS_SEND_SIZE(struct qtreq_mkdir, req->path));
@@ -902,7 +902,7 @@ int qtfs_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool exc
 	}
 
 	req = pvar->conn_ops->get_conn_msg_buf(pvar, QTFS_SEND);
-	QTFS_FULLNAME(req->path, dentry);
+	QTFS_FULLNAME(req->path, dentry, sizeof(req->path));
 
 	req->mode = mode;
 	req->excl = excl;
@@ -946,7 +946,7 @@ int qtfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev
 	}
 
 	req = pvar->conn_ops->get_conn_msg_buf(pvar, QTFS_SEND);
-	QTFS_FULLNAME(req->path, dentry);
+	QTFS_FULLNAME(req->path, dentry, sizeof(req->path));
 
 	req->mode = mode;
 	req->dev = dev;
@@ -1048,7 +1048,7 @@ struct dentry *qtfs_lookup(struct inode *parent_inode, struct dentry *child_dent
 	}
 
 	req = pvar->conn_ops->get_conn_msg_buf(pvar, QTFS_SEND);
-	ret = qtfs_fullname(req->fullname, child_dentry);
+	ret = qtfs_fullname(req->fullname, child_dentry, sizeof(req->fullname));
 	if (ret < 0) {
 		qtfs_err("qtfs lookup get fullname failed, too many path layers, <%s>!", req->fullname);
 		goto err_end;
@@ -1092,7 +1092,7 @@ int qtfs_rmdir(struct inode *dir, struct dentry *dentry)
 	}
 
 	req = pvar->conn_ops->get_conn_msg_buf(pvar, QTFS_SEND);
-	QTFS_FULLNAME(req->path, dentry);
+	QTFS_FULLNAME(req->path, dentry, sizeof(req->path));
 
 	rsp = qtfs_remote_run(pvar, QTFS_REQ_RMDIR, QTFS_SEND_SIZE(struct qtreq_rmdir, req->path));
 	if (IS_ERR_OR_NULL(rsp)) {
@@ -1128,7 +1128,7 @@ int qtfs_unlink(struct inode *dir, struct dentry *dentry)
 	}
 
 	req = pvar->conn_ops->get_conn_msg_buf(pvar, QTFS_SEND);
-	QTFS_FULLNAME(req->path, dentry);
+	QTFS_FULLNAME(req->path, dentry, sizeof(req->path));
 	qtfs_info("qtfs unlink %s.\n", req->path);
 
 	rsp = qtfs_remote_run(pvar, QTFS_REQ_UNLINK, QTFS_SEND_SIZE(struct qtreq_unlink, req->path));
@@ -1164,9 +1164,9 @@ int qtfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_d
 	}
 
 	req = pvar->conn_ops->get_conn_msg_buf(pvar, QTFS_SEND);
-	QTFS_FULLNAME(req->path, old_dentry);
+	QTFS_FULLNAME(req->path, old_dentry, sizeof(req->path));
 	req->d.oldlen = strlen(req->path) + 1;
-	QTFS_FULLNAME(req->path + req->d.oldlen, new_dentry);
+	QTFS_FULLNAME(req->path + req->d.oldlen, new_dentry, sizeof(req->path) - req->d.oldlen);
 	req->d.newlen = strlen(req->path + req->d.oldlen) + 1;
 	rsp = qtfs_remote_run(pvar, QTFS_REQ_LINK, sizeof(struct qtreq_link) - sizeof(req->path) + req->d.newlen + req->d.oldlen);
 	if (IS_ERR_OR_NULL(rsp)) {
@@ -1209,7 +1209,7 @@ int qtfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
 	}
 
 	req = pvar->conn_ops->get_conn_msg_buf(pvar, QTFS_SEND);
-	QTFS_FULLNAME(req->path, dentry);
+	QTFS_FULLNAME(req->path, dentry, sizeof(req->path));
 	req->d.newlen = strlen(req->path) + 1;
 	if (req->d.newlen + strlen(symname) + 1 > sizeof(req->path)) {
 		qtfs_conn_put_param(pvar);
@@ -1259,7 +1259,7 @@ int qtfs_getattr(const struct path *path, struct kstat *stat, u32 req_mask, unsi
 	}
 
 	req = pvar->conn_ops->get_conn_msg_buf(pvar, QTFS_SEND);
-	QTFS_FULLNAME(req->path, path->dentry);
+	QTFS_FULLNAME(req->path, path->dentry, sizeof(req->path));
 	req->request_mask = req_mask;
 	req->query_flags = flags;
 	mnt_path = qtfs_mountpoint_path_init(path->dentry, (struct path*)path, req->path);
@@ -1308,7 +1308,7 @@ int qtfs_setattr(struct dentry *dentry, struct iattr *attr)
 	}
 
 	req = pvar->conn_ops->get_conn_msg_buf(pvar, QTFS_SEND);
-	QTFS_FULLNAME(req->path, dentry);
+	QTFS_FULLNAME(req->path, dentry, sizeof(req->path));
 	req->attr = *attr;
 	req->attr.ia_file = NULL;
 	qtfs_info("iattr iavalid:%u mode:0x%o size:%lld file:0x%lx\n",
@@ -1355,7 +1355,7 @@ const char *qtfs_getlink(struct dentry *dentry,
 	}
 
 	req = pvar->conn_ops->get_conn_msg_buf(pvar, QTFS_SEND);
-	if (qtfs_fullname(req->path, dentry) < 0) {
+	if (qtfs_fullname(req->path, dentry, sizeof(req->path)) < 0) {
 		qtfs_err("qtfs fullname failed\n");
 		qtfs_conn_put_param(pvar);
 		return ERR_PTR(-EINVAL);
@@ -1416,14 +1416,14 @@ int qtfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	}
 
 	req = pvar->conn_ops->get_conn_msg_buf(pvar, QTFS_SEND);
-	req->d.oldlen = qtfs_fullname(req->path, old_dentry);
+	req->d.oldlen = qtfs_fullname(req->path, old_dentry, sizeof(req->path));
 	if (req->d.oldlen < 0) {
 		qtfs_err("qtfs fullname failed\n");
 		qtfs_conn_put_param(pvar);
 		return -EINVAL;
 	}
 	req->d.oldlen += 1;
-	req->d.newlen = qtfs_fullname(&req->path[req->d.oldlen], new_dentry);
+	req->d.newlen = qtfs_fullname(&req->path[req->d.oldlen], new_dentry, sizeof(req->path) - req->d.oldlen);
 	if (req->d.newlen < 0) {
 		qtfs_err("qtfs fullname failed\n");
 		qtfs_conn_put_param(pvar);
diff --git a/qtfs/qtfs/syscall.c b/qtfs/qtfs/syscall.c
index 5d4d38b2f615d9208393500fd734f361fd925b19..64c26923d2e2cb5b54837b27a0967ba74d23b387 100644
--- a/qtfs/qtfs/syscall.c
+++ b/qtfs/qtfs/syscall.c
@@ -137,7 +137,7 @@ int qtfs_epoll_ctl_remote(int op, int fd, struct epoll_event __user * event)
 			goto end;
 		}
 		memset(fullname, 0, MAX_PATH_LEN);
-		if (qtfs_fullname(fullname, file->f_path.dentry) < 0) {
+		if (qtfs_fullname(fullname, file->f_path.dentry, MAX_PATH_LEN) < 0) {
 			qtfs_err("qtfs fullname failed\n");
 			kfree(fullname);
 			ret = -1;
@@ -246,7 +246,7 @@ int qtfs_dir_to_qtdir(char *dir, char *qtdir)
 	if (strcmp(path.mnt->mnt_sb->s_type->name, QTFS_FSTYPE_NAME)) {
 		strcpy(qtdir, dir);
 	} else {
-		ret = qtfs_fullname(qtdir, path.dentry);
+		ret = qtfs_fullname(qtdir, path.dentry, len);
 	}
 	path_put(&path);
 	return ret;
diff --git a/qtfs/qtfs/xattr.c b/qtfs/qtfs/xattr.c
index 2dfb9fd48d91f28bd762becfcec0857442f8ab79..1ad484af87bc4baffcd687ba5fc6aaab7f564f7e 100644
--- a/qtfs/qtfs/xattr.c
+++ b/qtfs/qtfs/xattr.c
@@ -39,7 +39,7 @@ ssize_t qtfs_xattr_list(struct dentry *dentry, char *buffer, size_t buffer_size)
 	}
 
 	req = pvar->conn_ops->get_conn_msg_buf(pvar, QTFS_SEND);
-	if (qtfs_fullname(req->path, dentry) < 0) {
+	if (qtfs_fullname(req->path, dentry, sizeof(req->path)) < 0) {
 		qtfs_err("qtfs fullname failed");
 		qtfs_conn_put_param(pvar);
 		return 0;
@@ -142,7 +142,7 @@ static int qtfs_xattr_set(const struct xattr_handler *handler,
 		return -ENOENT;
 	}
 	req = pvar->conn_ops->get_conn_msg_buf(pvar, QTFS_SEND);
-	if (qtfs_fullname(req->buf, dentry) < 0) {
+	if (qtfs_fullname(req->buf, dentry, sizeof(req->buf)) < 0) {
 		qtfs_err("xattr set get fullname failed.");
 		qtfs_conn_put_param(pvar);
 		return -EFAULT;
@@ -197,7 +197,7 @@ static int qtfs_xattr_get(const struct xattr_handler *handler,
 	}
 
 	req = pvar->conn_ops->get_conn_msg_buf(pvar, QTFS_SEND);
-	if (qtfs_fullname(req->path, dentry) < 0) {
+	if (qtfs_fullname(req->path, dentry, sizeof(req->path)) < 0) {
 		qtfs_err("qtfs fullname failed");
 		qtfs_conn_put_param(pvar);
 		return 0;