From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B4532C433EF for ; Mon, 13 Jun 2022 14:32:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1383670AbiFMObv (ORCPT ); Mon, 13 Jun 2022 10:31:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35220 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1385105AbiFMOai (ORCPT ); Mon, 13 Jun 2022 10:30:38 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7A8EDA86A5; Mon, 13 Jun 2022 04:48:35 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 92360612AC; Mon, 13 Jun 2022 11:48:01 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 77806C3411C; Mon, 13 Jun 2022 11:48:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1655120881; bh=xiYEgWBVMCuIUkmI5EK4524c4rH/1oU6YNVnXbs2OsU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CewKg/IPdo05yYZhMRum+2tIyjM380BAQY1OwLXVbbdV1I87Ki+oWDuC/L1Ivbj0k 1Z/hrjQ5oPP8D+iXQFKCVcWUrLIJzmQmv3xRXsBYFzBaWx0X9hSmS1iegkGpyc0FXN GmUdG5dWc6X/9EFmmSSvQzNMgYfGcfymKX6YqPtA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, kernel test robot , Dan Carpenter , Taehee Yoo , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.17 169/298] amt: fix possible null-ptr-deref in amt_rcv() Date: Mon, 13 Jun 2022 12:11:03 +0200 Message-Id: <20220613094930.057866332@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220613094924.913340374@linuxfoundation.org> References: <20220613094924.913340374@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Taehee Yoo [ Upstream commit d16207f92a4a823c48b4ea953ad51f4483456768 ] When amt interface receives amt message, it tries to obtain amt private data from sock. If there is no amt private data, it frees an skb immediately. After kfree_skb(), it increases the rx_dropped stats. But in order to use rx_dropped, amt private data is needed. So, it makes amt_rcv() to do not increase rx_dropped stats when it can not obtain amt private data. Reported-by: kernel test robot Reported-by: Dan Carpenter Fixes: 1a1a0e80e005 ("amt: fix possible memory leak in amt_rcv()") Signed-off-by: Taehee Yoo Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/amt.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/amt.c b/drivers/net/amt.c index d8c47c4e6559..e239c0262d56 100644 --- a/drivers/net/amt.c +++ b/drivers/net/amt.c @@ -2698,7 +2698,8 @@ static int amt_rcv(struct sock *sk, struct sk_buff *skb) amt = rcu_dereference_sk_user_data(sk); if (!amt) { err = true; - goto drop; + kfree_skb(skb); + goto out; } skb->dev = amt->dev; -- 2.35.1