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=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 8E970C282C8 for ; Mon, 28 Jan 2019 16:34:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 55AE1204EC for ; Mon, 28 Jan 2019 16:34:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548693242; bh=coPPtY93kHQgqoCp5iWSNXYKSkTXmBl115yEVy2kBaw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=xv9nkHCHVUnVMyFt6mg2JCIw74mBGdTSoPZFI0u1U4pxO/HynGGRi0vIw2noGXDHj 6R7b9koaWRFlvf5Xa7xNwBq6GX5paUTFxd4Ao7gsGtntpPSLiur/JhficLtWWsTjew RVXrtajHYKsUSvYSEuebv2FAkYdXzY/RHfKihAkQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390117AbfA1Q0O (ORCPT ); Mon, 28 Jan 2019 11:26:14 -0500 Received: from mail.kernel.org ([198.145.29.99]:35400 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390135AbfA1Q0N (ORCPT ); Mon, 28 Jan 2019 11:26:13 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 05A1920879; Mon, 28 Jan 2019 16:26:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548692772; bh=coPPtY93kHQgqoCp5iWSNXYKSkTXmBl115yEVy2kBaw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0rqX8rHRFU1aZR3rER5ON9Q9pu0lJ6Dur3BR0qt81O9yw3baxlxKNMDU+UeEWpfqR CVx+rzpNgVvo/m2dqKJ4g3RQuJ90WuR32Qcwjqvdgk7dawYbwsI+TZpdBvTWaHYr86 5HHA3vjb89P76BsRRwKRiDea5BTgUBcNZjpvxgkU= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Jia-Ju Bai , "David S . Miller" , Sasha Levin , netdev@vger.kernel.org Subject: [PATCH AUTOSEL 4.4 74/80] isdn: hisax: hfc_pci: Fix a possible concurrency use-after-free bug in HFCPCI_l1hw() Date: Mon, 28 Jan 2019 11:23:55 -0500 Message-Id: <20190128162401.58841-74-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190128162401.58841-1-sashal@kernel.org> References: <20190128162401.58841-1-sashal@kernel.org> MIME-Version: 1.0 X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Jia-Ju Bai [ 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 90449e1e91e5..1b1453d62fed 100644 --- a/drivers/isdn/hisax/hfc_pci.c +++ b/drivers/isdn/hisax/hfc_pci.c @@ -1169,11 +1169,13 @@ 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