diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
index f09afbdde58a..cb779d217234 100644
--- a/fs/ksmbd/smb2pdu.c
+++ b/fs/ksmbd/smb2pdu.c
@@ -7448,13 +7448,16 @@ static int fsctl_query_allocated_ranges(struct ksmbd_work *work, u64 id,
 	if (in_count == 0)
 		return -EINVAL;
 
+	start = le64_to_cpu(qar_req->file_offset);
+	length = le64_to_cpu(qar_req->length);
+
+	if (start < 0 || length < 0)
+		return -EINVAL;
+
 	fp = ksmbd_lookup_fd_fast(work, id);
 	if (!fp)
 		return -ENOENT;
 
-	start = le64_to_cpu(qar_req->file_offset);
-	length = le64_to_cpu(qar_req->length);
-
 	ret = ksmbd_vfs_fqar_lseek(fp, start, length,
 				   qar_rsp, in_count, out_count);
 	if (ret && ret != -E2BIG)