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=-13.1 required=3.0 tests=BAYES_00,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,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 572E2C433E2 for ; Tue, 21 Jul 2020 15:19:19 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 249C4206E3 for ; Tue, 21 Jul 2020 15:19:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="gpS8V+DE" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 249C4206E3 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=163.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:48732 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jxu34-0001eG-Ch for qemu-devel@archiver.kernel.org; Tue, 21 Jul 2020 11:19:18 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:50310) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jxu1s-0000CD-3x for qemu-devel@nongnu.org; Tue, 21 Jul 2020 11:18:04 -0400 Received: from mail-m975.mail.163.com ([123.126.97.5]:37908) by eggs.gnu.org with esmtps (TLS1.2:DHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jxu1k-0004c0-FH for qemu-devel@nongnu.org; Tue, 21 Jul 2020 11:18:01 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id; bh=LX1r6UYEMMR99TVv0H qbAyZ6SpgW/oGQ1MXAJ8cuMGk=; b=gpS8V+DEkckV6jNUgPtricDy2idilNVDEZ tpIgHZmVrVBlw1FUr0+mg1i3Ru2yCGBfXdi4RTOZOjm5SgXU1Y+cqH15sm5YonAs 6gaf1TtCKw7eAb5LUlolPDr7kaZgkwL5EZjzmY3C/khKqS7QhDmYp1wU5Ffcte9h /x35fOIxQ= Received: from localhost.localdomain (unknown [115.199.195.7]) by smtp5 (Coremail) with SMTP id HdxpCgBXEwsPBxdfdT58Dg--.162S4; Tue, 21 Jul 2020 23:17:37 +0800 (CST) From: Li Qiang To: dmitry.fleytman@gmail.com, jasowang@redhat.com, pbonzini@redhat.com Subject: [PATCH v3] e1000e: using bottom half to send packets Date: Tue, 21 Jul 2020 08:17:28 -0700 Message-Id: <20200721151728.112395-1-liq3ea@163.com> X-Mailer: git-send-email 2.17.1 X-CM-TRANSID: HdxpCgBXEwsPBxdfdT58Dg--.162S4 X-Coremail-Antispam: 1Uf129KBjvJXoWxtw4DJr47tw1fGFy8Jr4ruFg_yoW3Kr1xpa 97GwsxXr15Gry3Ars7Wry5Jr15Xr48J397Wr4Uu34FqFZ3A34DJr10ga1UZFZxZa9FvrZY kF45tr9F9rWDXw7anT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x07UDb1nUUUUU= X-Originating-IP: [115.199.195.7] X-CM-SenderInfo: 5oltjvrd6rljoofrz/1tbitBFobVSIh+n63wAAs3 Received-SPF: pass client-ip=123.126.97.5; envelope-from=liq3ea@163.com; helo=mail-m975.mail.163.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/07/21 11:17:45 X-ACL-Warn: Detected OS = Linux 3.1-3.10 X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: alxndr@bu.edu, Li Qiang , liq3ea@gmail.com, qemu-devel@nongnu.org, ppandit@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Alexander Bulekov reported a UAF bug related e1000e packets send. -->https://bugs.launchpad.net/qemu/+bug/1886362 This is because the guest trigger a e1000e packet send and set the data's address to e1000e's MMIO address. So when the e1000e do DMA it will write the MMIO again and trigger re-entrancy and finally causes this UAF. Paolo suggested to use a bottom half whenever MMIO is doing complicate things in here: -->https://lists.nongnu.org/archive/html/qemu-devel/2020-07/msg03342.html Reference here: 'The easiest solution is to delay processing of descriptors to a bottom half whenever MMIO is doing something complicated. This is also better for latency because it will free the vCPU thread more quickly and leave the work to the I/O thread.' This patch fixes this UAF. Reported-by: Alexander Bulekov Signed-off-by: Li Qiang --- Change since v2: 1. Add comments for the tx bh schdule when VM resumes 2. Leave the set ics code in 'e1000e_start_xmit' 3. Cancel the tx bh and reset tx_waiting in e1000e_core_reset Change since v1: Per Jason's review here: -- https://lists.nongnu.org/archive/html/qemu-devel/2020-07/msg05368.html 1. Cancel and schedule the tx bh when VM is stopped or resume 2. Add a tx_burst for e1000e configuration to throttle the bh execution 3. Add a tx_waiting to record whether the bh is pending or not Don't use BQL in the tx_bh handler as when tx_bh is executed, the BQL is acquired. hw/net/e1000e.c | 6 +++ hw/net/e1000e_core.c | 107 +++++++++++++++++++++++++++++++++++-------- hw/net/e1000e_core.h | 8 ++++ 3 files changed, 101 insertions(+), 20 deletions(-) diff --git a/hw/net/e1000e.c b/hw/net/e1000e.c index fda34518c9..24e35a78bf 100644 --- a/hw/net/e1000e.c +++ b/hw/net/e1000e.c @@ -77,10 +77,14 @@ typedef struct E1000EState { bool disable_vnet; + int32_t tx_burst; + E1000ECore core; } E1000EState; +#define TX_BURST 256 + #define E1000E_MMIO_IDX 0 #define E1000E_FLASH_IDX 1 #define E1000E_IO_IDX 2 @@ -263,6 +267,7 @@ static void e1000e_core_realize(E1000EState *s) { s->core.owner = &s->parent_obj; s->core.owner_nic = s->nic; + s->core.tx_burst = s->tx_burst; } static void @@ -665,6 +670,7 @@ static Property e1000e_properties[] = { e1000e_prop_subsys_ven, uint16_t), DEFINE_PROP_SIGNED("subsys", E1000EState, subsys, 0, e1000e_prop_subsys, uint16_t), + DEFINE_PROP_INT32("x-txburst", E1000EState, tx_burst, TX_BURST), DEFINE_PROP_END_OF_LIST(), }; diff --git a/hw/net/e1000e_core.c b/hw/net/e1000e_core.c index bcd186cac5..2fdfc23204 100644 --- a/hw/net/e1000e_core.c +++ b/hw/net/e1000e_core.c @@ -910,18 +910,17 @@ e1000e_rx_ring_init(E1000ECore *core, E1000E_RxRing *rxr, int idx) } static void -e1000e_start_xmit(E1000ECore *core, const E1000E_TxRing *txr) +e1000e_start_xmit(struct e1000e_tx *q) { + E1000ECore *core = q->core; dma_addr_t base; struct e1000_tx_desc desc; - bool ide = false; - const E1000E_RingInfo *txi = txr->i; - uint32_t cause = E1000_ICS_TXQE; + const E1000E_RingInfo *txi; + E1000E_TxRing txr; + int32_t num_packets = 0; - if (!(core->mac[TCTL] & E1000_TCTL_EN)) { - trace_e1000e_tx_disabled(); - return; - } + e1000e_tx_ring_init(core, &txr, q - &core->tx[0]); + txi = txr.i; while (!e1000e_ring_empty(core, txi)) { base = e1000e_ring_head_descr(core, txi); @@ -931,14 +930,24 @@ e1000e_start_xmit(E1000ECore *core, const E1000E_TxRing *txr) trace_e1000e_tx_descr((void *)(intptr_t)desc.buffer_addr, desc.lower.data, desc.upper.data); - e1000e_process_tx_desc(core, txr->tx, &desc, txi->idx); - cause |= e1000e_txdesc_writeback(core, base, &desc, &ide, txi->idx); + e1000e_process_tx_desc(core, txr.tx, &desc, txi->idx); + q->cause |= e1000e_txdesc_writeback(core, base, &desc, + &q->ide, txi->idx); e1000e_ring_advance(core, txi, 1); + if (++num_packets >= core->tx_burst) { + break; + } + } + + if (num_packets >= core->tx_burst) { + qemu_bh_schedule(q->tx_bh); + q->tx_waiting = 1; + return; } - if (!ide || !e1000e_intrmgr_delay_tx_causes(core, &cause)) { - e1000e_set_interrupt_cause(core, cause); + if (!q->ide || !e1000e_intrmgr_delay_tx_causes(core, &q->cause)) { + e1000e_set_interrupt_cause(core, q->cause); } } @@ -2423,32 +2432,41 @@ e1000e_set_dbal(E1000ECore *core, int index, uint32_t val) static void e1000e_set_tctl(E1000ECore *core, int index, uint32_t val) { - E1000E_TxRing txr; core->mac[index] = val; if (core->mac[TARC0] & E1000_TARC_ENABLE) { - e1000e_tx_ring_init(core, &txr, 0); - e1000e_start_xmit(core, &txr); + if (core->tx[0].tx_waiting) { + return; + } + core->tx[0].tx_waiting = 1; + if (!core->vm_running) { + return; + } + qemu_bh_schedule(core->tx[0].tx_bh); } if (core->mac[TARC1] & E1000_TARC_ENABLE) { - e1000e_tx_ring_init(core, &txr, 1); - e1000e_start_xmit(core, &txr); + if (core->tx[1].tx_waiting) { + return; + } + core->tx[1].tx_waiting = 1; + if (!core->vm_running) { + return; + } + qemu_bh_schedule(core->tx[1].tx_bh); } } static void e1000e_set_tdt(E1000ECore *core, int index, uint32_t val) { - E1000E_TxRing txr; int qidx = e1000e_mq_queue_idx(TDT, index); uint32_t tarc_reg = (qidx == 0) ? TARC0 : TARC1; core->mac[index] = val & 0xffff; if (core->mac[tarc_reg] & E1000_TARC_ENABLE) { - e1000e_tx_ring_init(core, &txr, qidx); - e1000e_start_xmit(core, &txr); + qemu_bh_schedule(core->tx[qidx].tx_bh); } } @@ -3315,11 +3333,52 @@ e1000e_vm_state_change(void *opaque, int running, RunState state) trace_e1000e_vm_state_running(); e1000e_intrmgr_resume(core); e1000e_autoneg_resume(core); + core->vm_running = 1; + + for (int i = 0; i < E1000E_NUM_QUEUES; i++) { + /* + * Schedule tx bh unconditionally to make sure + * tx work after live migration since we don't + * migrate tx_waiting. + */ + qemu_bh_schedule(core->tx[i].tx_bh); + } + } else { trace_e1000e_vm_state_stopped(); + + for (int i = 0; i < E1000E_NUM_QUEUES; i++) { + qemu_bh_cancel(core->tx[i].tx_bh); + } + e1000e_autoneg_pause(core); e1000e_intrmgr_pause(core); + core->vm_running = 0; + } +} + + +static void e1000e_core_tx_bh(void *opaque) +{ + struct e1000e_tx *q = opaque; + E1000ECore *core = q->core; + + if (!core->vm_running) { + assert(q->tx_waiting); + return; + } + + q->tx_waiting = 0; + + if (!(core->mac[TCTL] & E1000_TCTL_EN)) { + trace_e1000e_tx_disabled(); + return; } + + q->cause = E1000_ICS_TXQE; + q->ide = false; + + e1000e_start_xmit(q); } void @@ -3334,12 +3393,15 @@ e1000e_core_pci_realize(E1000ECore *core, e1000e_autoneg_timer, core); e1000e_intrmgr_pci_realize(core); + core->vm_running = runstate_is_running(); core->vmstate = qemu_add_vm_change_state_handler(e1000e_vm_state_change, core); for (i = 0; i < E1000E_NUM_QUEUES; i++) { net_tx_pkt_init(&core->tx[i].tx_pkt, core->owner, E1000E_MAX_TX_FRAGS, core->has_vnet); + core->tx[i].core = core; + core->tx[i].tx_bh = qemu_bh_new(e1000e_core_tx_bh, &core->tx[i]); } net_rx_pkt_init(&core->rx_pkt, core->has_vnet); @@ -3367,6 +3429,9 @@ e1000e_core_pci_uninit(E1000ECore *core) for (i = 0; i < E1000E_NUM_QUEUES; i++) { net_tx_pkt_reset(core->tx[i].tx_pkt); net_tx_pkt_uninit(core->tx[i].tx_pkt); + qemu_bh_cancel(core->tx[i].tx_bh); + qemu_bh_delete(core->tx[i].tx_bh); + core->tx[i].tx_bh = NULL; } net_rx_pkt_uninit(core->rx_pkt); @@ -3480,6 +3545,8 @@ e1000e_core_reset(E1000ECore *core) net_tx_pkt_reset(core->tx[i].tx_pkt); memset(&core->tx[i].props, 0, sizeof(core->tx[i].props)); core->tx[i].skip_cp = false; + qemu_bh_cancel(core->tx[i].tx_bh); + core->tx[i].tx_waiting = 0; } } diff --git a/hw/net/e1000e_core.h b/hw/net/e1000e_core.h index aee32f7e48..0c16dce3a6 100644 --- a/hw/net/e1000e_core.h +++ b/hw/net/e1000e_core.h @@ -77,10 +77,18 @@ struct E1000Core { unsigned char sum_needed; bool cptse; struct NetTxPkt *tx_pkt; + QEMUBH *tx_bh; + uint32_t tx_waiting; + uint32_t cause; + bool ide; + E1000ECore *core; } tx[E1000E_NUM_QUEUES]; struct NetRxPkt *rx_pkt; + int32_t tx_burst; + + bool vm_running; bool has_vnet; int max_queue_num; -- 2.17.1