diff --git a/fs/smb/server/vfs.c b/fs/smb/server/vfs.c
index 25e8004a5905..cf1b241a1578 100644
--- a/fs/smb/server/vfs.c
+++ b/fs/smb/server/vfs.c
@@ -440,6 +440,13 @@ static int ksmbd_vfs_stream_write(struct ksmbd_file *fp, char *buf, loff_t *pos,
 		goto out;
 	}
 
+	if (v_len <= *pos) {
+		pr_err("stream write position %lld is out of bounds (stream length: %zd)\n",
+				*pos, v_len);
+		err = -EINVAL;
+		goto out;
+	}
+
 	if (v_len < size) {
 		wbuf = kvzalloc(size, GFP_KERNEL);
 		if (!wbuf) {