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 15738C433F5 for ; Fri, 10 Dec 2021 11:32:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237408AbhLJLfz (ORCPT ); Fri, 10 Dec 2021 06:35:55 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43194 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234921AbhLJLfy (ORCPT ); Fri, 10 Dec 2021 06:35:54 -0500 Received: from sin.source.kernel.org (sin.source.kernel.org [IPv6:2604:1380:40e1:4800::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 149ACC061746 for ; Fri, 10 Dec 2021 03:32:20 -0800 (PST) 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 sin.source.kernel.org (Postfix) with ESMTPS id 612C0CE24EF for ; Fri, 10 Dec 2021 11:32:18 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0E6EBC00446; Fri, 10 Dec 2021 11:32:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1639135936; bh=WiX0wLRtnCCxcBCTEZjwRgdM4kRKy+1rJBhaRmvXsYU=; h=Subject:To:Cc:From:Date:From; b=sf+yUhLecasEQNSGkjekXLN4TRT39HdYnk4eq1TYeScYmb3bsEtY0YCRguAIbysA4 bcvB9Koj1MNbV7O+yYwlAJPZIbNbBXjlct8WyWZdLeTIkqFdUTGgqUM/qq1W1JzBxB KgQhU4Fnle7XFRfGTvr2tXNw9TW3LMcyflWEeSsw= Subject: FAILED: patch "[PATCH] can: pch_can: pch_can_rx_normal: fix use after free" failed to apply to 4.9-stable tree To: mailhol.vincent@wanadoo.fr, mkl@pengutronix.de Cc: From: Date: Fri, 10 Dec 2021 12:32:05 +0100 Message-ID: <1639135925156182@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 94cddf1e9227a171b27292509d59691819c458db Mon Sep 17 00:00:00 2001 From: Vincent Mailhol Date: Tue, 23 Nov 2021 20:16:54 +0900 Subject: [PATCH] can: pch_can: pch_can_rx_normal: fix use after free After calling netif_receive_skb(skb), dereferencing skb is unsafe. Especially, the can_frame cf which aliases skb memory is dereferenced just after the call netif_receive_skb(skb). Reordering the lines solves the issue. Fixes: b21d18b51b31 ("can: Topcliff: Add PCH_CAN driver.") Link: https://lore.kernel.org/all/20211123111654.621610-1-mailhol.vincent@wanadoo.fr Cc: stable@vger.kernel.org Signed-off-by: Vincent Mailhol Signed-off-by: Marc Kleine-Budde diff --git a/drivers/net/can/pch_can.c b/drivers/net/can/pch_can.c index 92a54a5fd4c5..964c8a09226a 100644 --- a/drivers/net/can/pch_can.c +++ b/drivers/net/can/pch_can.c @@ -692,11 +692,11 @@ static int pch_can_rx_normal(struct net_device *ndev, u32 obj_num, int quota) cf->data[i + 1] = data_reg >> 8; } - netif_receive_skb(skb); rcv_pkts++; stats->rx_packets++; quota--; stats->rx_bytes += cf->len; + netif_receive_skb(skb); pch_fifo_thresh(priv, obj_num); obj_num++;