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 029BEC388F3 for ; Tue, 10 May 2022 13:44:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245490AbiEJNrr (ORCPT ); Tue, 10 May 2022 09:47:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56970 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243993AbiEJNcZ (ORCPT ); Tue, 10 May 2022 09:32:25 -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 122BB1B5FAE; Tue, 10 May 2022 06:23:59 -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 88AC76175F; Tue, 10 May 2022 13:23:58 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 95EA2C385C2; Tue, 10 May 2022 13:23:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1652189038; bh=uZMOLfy6eiL9LYCuuMPoUD+KDOWsUnsgqeVOwCZTtgk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eYo1TvmkiyMz5fvI5VzX2fgq2XuW5lUQT3G7gQmtj3/1iXTIWkZM+5dSpXvQDAdR8 XcEXgCYzwKRaY4PB07TjT0xOotc6yeh46ja0CGB+OunxY/F+y0P/3looqCuUd6sAXv xFSQ66/8tEVh5xdDhsg/CBjUa8mUzahxge1db4kE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Chengfeng Ye , Takashi Sakamoto , Takashi Iwai Subject: [PATCH 5.4 06/52] firewire: fix potential uaf in outbound_phy_packet_callback() Date: Tue, 10 May 2022 15:07:35 +0200 Message-Id: <20220510130730.044041189@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220510130729.852544477@linuxfoundation.org> References: <20220510130729.852544477@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: linux-kernel@vger.kernel.org From: Chengfeng Ye commit b7c81f80246fac44077166f3e07103affe6db8ff upstream. &e->event and e point to the same address, and &e->event could be freed in queue_event. So there is a potential uaf issue if we dereference e after calling queue_event(). Fix this by adding a temporary variable to maintain e->client in advance, this can avoid the potential uaf issue. Cc: Signed-off-by: Chengfeng Ye Signed-off-by: Takashi Sakamoto Link: https://lore.kernel.org/r/20220409041243.603210-2-o-takashi@sakamocchi.jp Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- drivers/firewire/core-cdev.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/firewire/core-cdev.c +++ b/drivers/firewire/core-cdev.c @@ -1482,6 +1482,7 @@ static void outbound_phy_packet_callback { struct outbound_phy_packet_event *e = container_of(packet, struct outbound_phy_packet_event, p); + struct client *e_client; switch (status) { /* expected: */ @@ -1498,9 +1499,10 @@ static void outbound_phy_packet_callback } e->phy_packet.data[0] = packet->timestamp; + e_client = e->client; queue_event(e->client, &e->event, &e->phy_packet, sizeof(e->phy_packet) + e->phy_packet.length, NULL, 0); - client_put(e->client); + client_put(e_client); } static int ioctl_send_phy_packet(struct client *client, union ioctl_arg *arg)