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 X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 558CFC282CE for ; Mon, 11 Feb 2019 14:33:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1EAB52081B for ; Mon, 11 Feb 2019 14:33:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1549895636; bh=ieiwnAJO+rS8b6oJr17uZhN4tnm095mIePEvGJ+odlg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Ke5OBrsFCP+2FTkwqgj0FywpyFlUkVVJcs+dEEdH5RspNOSZeSviQo2l2R8cUmd5e egwlODKusRre4JbrRgnANN77HjsQqFLYl1gcnnmU/d/qyPHLOPNWzpyr9RiilrfbF+ lQwQ0Fu1DFvGv2zb9p7oXaCySprHHWqE0gsNDNTA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730762AbfBKOdz (ORCPT ); Mon, 11 Feb 2019 09:33:55 -0500 Received: from mail.kernel.org ([198.145.29.99]:41878 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730759AbfBKOdy (ORCPT ); Mon, 11 Feb 2019 09:33:54 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E5825204EC; Mon, 11 Feb 2019 14:33:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1549895633; bh=ieiwnAJO+rS8b6oJr17uZhN4tnm095mIePEvGJ+odlg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=il5Nof00XrLmGbR9By+XVhNtS7jM4ChxbgI9+DmVcPDb30+iNZVqirHvqhg1jdUf6 SqxPK2hzmUHxCn7xoOvfPvOlrDiBbxlz5xq8ZQVQXNb5RnQLcvJrmDlSjgB3eEK4oi p9Xpw+ubPdlO0qnK9rpzcU4z1T5sNtpGJOfLjHBI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jia-Ju Bai , "David S. Miller" , Sasha Levin Subject: [PATCH 4.20 270/352] isdn: hisax: hfc_pci: Fix a possible concurrency use-after-free bug in HFCPCI_l1hw() Date: Mon, 11 Feb 2019 15:18:17 +0100 Message-Id: <20190211141904.181569597@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190211141846.543045703@linuxfoundation.org> References: <20190211141846.543045703@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 4.20-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit 7418e6520f22a2e35815122fa5a53d5bbfa2c10f ] In drivers/isdn/hisax/hfc_pci.c, the functions hfcpci_interrupt() and HFCPCI_l1hw() may be concurrently executed. HFCPCI_l1hw() line 1173: if (!cs->tx_skb) hfcpci_interrupt() line 942: spin_lock_irqsave(); line 1066: dev_kfree_skb_irq(cs->tx_skb); Thus, a possible concurrency use-after-free bug may occur in HFCPCI_l1hw(). To fix these bugs, the calls to spin_lock_irqsave() and spin_unlock_irqrestore() are added in HFCPCI_l1hw(), to protect the access to cs->tx_skb. Signed-off-by: Jia-Ju Bai Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/isdn/hisax/hfc_pci.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/isdn/hisax/hfc_pci.c b/drivers/isdn/hisax/hfc_pci.c index ea0e4c6de3fb..0109e0e8bcb6 100644 --- a/drivers/isdn/hisax/hfc_pci.c +++ b/drivers/isdn/hisax/hfc_pci.c @@ -1170,11 +1170,13 @@ HFCPCI_l1hw(struct PStack *st, int pr, void *arg) if (cs->debug & L1_DEB_LAPD) debugl1(cs, "-> PH_REQUEST_PULL"); #endif + spin_lock_irqsave(&cs->lock, flags); if (!cs->tx_skb) { test_and_clear_bit(FLG_L1_PULL_REQ, &st->l1.Flags); st->l1.l1l2(st, PH_PULL | CONFIRM, NULL); } else test_and_set_bit(FLG_L1_PULL_REQ, &st->l1.Flags); + spin_unlock_irqrestore(&cs->lock, flags); break; case (HW_RESET | REQUEST): spin_lock_irqsave(&cs->lock, flags); -- 2.19.1