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=-8.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,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 4FB01C04AB3 for ; Wed, 29 May 2019 08:47:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 26D1420B1F for ; Wed, 29 May 2019 08:47:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="kzwVn+48" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726365AbfE2Ir4 (ORCPT ); Wed, 29 May 2019 04:47:56 -0400 Received: from mail-pf1-f195.google.com ([209.85.210.195]:44041 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726441AbfE2Irv (ORCPT ); Wed, 29 May 2019 04:47:51 -0400 Received: by mail-pf1-f195.google.com with SMTP id g9so1161565pfo.11; Wed, 29 May 2019 01:47:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=TgWBMzeoaoEO+5BjILyNWDtEoQ8YNu+FEzYYyIocJk8=; b=kzwVn+489j0EgyGtZJe7IBnMsoNMIAlsRcGhFOoe7UqlQNpgfLcFvu5VE16cEHkHaM ACvNDjzN8h/hZIPbOqc/H1ppKdLdnxwOEF/vBfGTJt3EDJn/8YmInhqonNTSbVHPast2 YkAf5ZyDYXv4r5jkHpT0vb5bx5810IEMkgG+hNPhpyq/xFLN4xuzdl/tpXosEVafooYv KKT2b8w4DpNZOVZo2qyfO+KtsgpPJgMiKNuDj7FT130tqOb5k6WisbqhBWXNjYJQFG3O nJQdMmNTl/UBeGW3TLSITdeIFQqIz5f7gJz0H2Vm3TzkVFpf0DM/61Pcz9Rz/Kt2dVro /EGA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=TgWBMzeoaoEO+5BjILyNWDtEoQ8YNu+FEzYYyIocJk8=; b=gHavSPLBiu9mAdCh0uKEEdHuzNtPe1XYMqrCkET9754T9lQFELmpDErqg0FFPs7V/c 49Tm6sW9femEkAKDeeoUDbDW2W01jzeA0FuwSg9bGgbpTFjuVRZPpHVPzf0QWEJCR9jQ AEoggDjdyHfVsUFjSRSRfbPbAtnYChfy70vq+A+PppRs/jFbKlp/N26jruwXFeqVhErU X2hgSU+RfyQ6giheLKMCpB11V6vhbi/Ukav/a227w296X8QmqXrcxgUM//B+PyJrasCU SREPLRCOjfrpvYIfwI//QtE0fQZEJ9NynUqP0tFZDxAcSmLZeUBz2I4p/KljiSy0QnE6 vkQw== X-Gm-Message-State: APjAAAUJeCRChVDeBlR0t8thR7Ka7IbvJ/SX97WEpu0fGBjLlrMGYPFp vp+AQ+PvXjmDzYyyNshBHTU= X-Google-Smtp-Source: APXvYqxE59mLhsE+Vd7Je+BFBDHnGy0F4hye4KgMKoXaxr51JgDgxDrpr5A6jhtiE/qAk+9FLSSoDw== X-Received: by 2002:a62:ee04:: with SMTP id e4mr33779311pfi.232.1559119671409; Wed, 29 May 2019 01:47:51 -0700 (PDT) Received: from xy-data.openstacklocal (ecs-159-138-22-150.compute.hwclouds-dns.com. [159.138.22.150]) by smtp.gmail.com with ESMTPSA id 24sm3191491pgn.32.2019.05.29.01.47.49 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 29 May 2019 01:47:50 -0700 (PDT) From: Young Xiao <92siuyang@gmail.com> To: isdn@linux-pingi.de, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Young Xiao <92siuyang@gmail.com> Subject: [PATCH] isdn: hisax: isac: fix a possible concurrency use-after-free bug in ISAC_l1hw() Date: Wed, 29 May 2019 16:48:59 +0800 Message-Id: <1559119739-27588-1-git-send-email-92siuyang@gmail.com> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In drivers/isdn/hisax/isac.c, the function isac_interrupt() and ISAC_l1hw() may be concurrently executed. ISAC_l1hw() line 499: if (!cs->tx_skb) isac_interrupt() line 250: dev_kfree_skb_irq(cs->tx_skb); Thus, a possible concurrency use-after-free bug may occur in ISAC_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. See commit 7418e6520f22 ("isdn: hisax: hfc_pci: Fix a possible concurrency use-after-free bug in HFCPCI_l1hw()") for details. Signed-off-by: Young Xiao <92siuyang@gmail.com> --- drivers/isdn/hisax/isac.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/isdn/hisax/isac.c b/drivers/isdn/hisax/isac.c index bd40e06..60dd805 100644 --- a/drivers/isdn/hisax/isac.c +++ b/drivers/isdn/hisax/isac.c @@ -496,11 +496,13 @@ ISAC_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); -- 2.7.4