From patchwork Mon Sep 23 10:11:12 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Krishnamraju Eraparaju X-Patchwork-Id: 11156555 X-Patchwork-Delegate: jgg@ziepe.ca Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id CD8C2112B for ; Mon, 23 Sep 2019 10:11:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B5E0120865 for ; Mon, 23 Sep 2019 10:11:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728994AbfIWKLW (ORCPT ); Mon, 23 Sep 2019 06:11:22 -0400 Received: from stargate.chelsio.com ([12.32.117.8]:23447 "EHLO stargate.chelsio.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728748AbfIWKLW (ORCPT ); Mon, 23 Sep 2019 06:11:22 -0400 Received: from localhost (budha.blr.asicdesigners.com [10.193.185.4]) by stargate.chelsio.com (8.13.8/8.13.8) with ESMTP id x8NABGT5010803; Mon, 23 Sep 2019 03:11:18 -0700 From: Krishnamraju Eraparaju To: jgg@ziepe.ca, bmt@zurich.ibm.com Cc: linux-rdma@vger.kernel.org, bharat@chelsio.com, nirranjan@chelsio.com, Krishnamraju Eraparaju Subject: [PATCH for-next] RDMA/siw: fixes serialization issue in write_space Date: Mon, 23 Sep 2019 15:41:12 +0530 Message-Id: <20190923101112.32685-1-krishna2@chelsio.com> X-Mailer: git-send-email 2.23.0.rc0 MIME-Version: 1.0 Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org In siw_qp_llp_write_space(), 'sock' members should be accessed with sk_callback_lock held, otherwise, it could race with siw_sk_restore_upcalls(). And this could cause "NULL deref" panic. Below panic is due to the NULL cep returned from sk_to_cep(sk): [14524.030863] Call Trace: [14524.030868] siw_qp_llp_write_space+0x11/0x40 [siw] [14524.030873] tcp_check_space+0x4c/0xf0 [14524.030877] tcp_rcv_established+0x52b/0x630 [14524.030880] tcp_v4_do_rcv+0xf4/0x1e0 [14524.030882] tcp_v4_rcv+0x9b8/0xab0 [14524.030886] ip_protocol_deliver_rcu+0x2c/0x1c0 [14524.030889] ip_local_deliver_finish+0x44/0x50 [14524.030891] ip_local_deliver+0x6b/0xf0 [14524.030893] ? ip_protocol_deliver_rcu+0x1c0/0x1c0 [14524.030896] ip_rcv+0x52/0xd0 [14524.030898] ? ip_rcv_finish_core.isra.14+0x390/0x390 [14524.030903] __netif_receive_skb_one_core+0x83/0xa0 [14524.030906] netif_receive_skb_internal+0x73/0xb0 [14524.030909] napi_gro_frags+0x1ff/0x2b0 [14524.030922] t4_ethrx_handler+0x4a7/0x740 [cxgb4] [14524.030930] process_responses+0x2c9/0x590 [cxgb4] [14524.030937] ? t4_sge_intr_msix+0x1d/0x30 [cxgb4] [14524.030941] ? handle_irq_event_percpu+0x51/0x70 [14524.030943] ? handle_irq_event+0x41/0x60 [14524.030946] ? handle_edge_irq+0x97/0x1a0 [14524.030952] napi_rx_handler+0x14/0xe0 [cxgb4] [14524.030955] net_rx_action+0x2af/0x410 [14524.030962] __do_softirq+0xda/0x2a8 [14524.030965] do_softirq_own_stack+0x2a/0x40 [14524.030967] [14524.030969] do_softirq+0x50/0x60 [14524.030972] __local_bh_enable_ip+0x50/0x60 [14524.030974] ip_finish_output2+0x18f/0x520 [14524.030977] ip_output+0x6e/0xf0 [14524.030979] ? __ip_finish_output+0x1f0/0x1f0 [14524.030982] __ip_queue_xmit+0x14f/0x3d0 [14524.030986] ? __slab_alloc+0x4b/0x58 [14524.030990] __tcp_transmit_skb+0x57d/0xa60 [14524.030992] tcp_write_xmit+0x23b/0xfd0 [14524.030995] __tcp_push_pending_frames+0x2e/0xf0 [14524.030998] tcp_sendmsg_locked+0x939/0xd50 [14524.031001] tcp_sendmsg+0x27/0x40 [14524.031004] sock_sendmsg+0x57/0x80 [14524.031009] siw_tx_hdt+0x894/0xb20 [siw] [14524.031015] ? find_busiest_group+0x3e/0x5b0 [14524.031019] ? common_interrupt+0xa/0xf [14524.031021] ? common_interrupt+0xa/0xf [14524.031023] ? common_interrupt+0xa/0xf [14524.031028] siw_qp_sq_process+0xf1/0xe60 [siw] [14524.031031] ? __wake_up_common_lock+0x87/0xc0 [14524.031035] siw_sq_resume+0x33/0xe0 [siw] [14524.031039] siw_run_sq+0xac/0x190 [siw] [14524.031041] ? remove_wait_queue+0x60/0x60 [14524.031045] kthread+0xf8/0x130 [14524.031049] ? siw_sq_resume+0xe0/0xe0 [siw] [14524.031051] ? kthread_bind+0x10/0x10 [14524.031053] ret_from_fork+0x35/0x40 Fixes: f29dd55b0236 (rdma/siw: queue pair methods) Signed-off-by: Krishnamraju Eraparaju Reviewed-by: Bernard Metzler --- drivers/infiniband/sw/siw/siw_qp.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/drivers/infiniband/sw/siw/siw_qp.c b/drivers/infiniband/sw/siw/siw_qp.c index 430314c8abd9..52d402f39df9 100644 --- a/drivers/infiniband/sw/siw/siw_qp.c +++ b/drivers/infiniband/sw/siw/siw_qp.c @@ -182,12 +182,19 @@ void siw_qp_llp_close(struct siw_qp *qp) */ void siw_qp_llp_write_space(struct sock *sk) { - struct siw_cep *cep = sk_to_cep(sk); + struct siw_cep *cep; - cep->sk_write_space(sk); + read_lock(&sk->sk_callback_lock); + + cep = sk_to_cep(sk); + if (cep) { + cep->sk_write_space(sk); - if (!test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) - (void)siw_sq_start(cep->qp); + if (!test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) + (void)siw_sq_start(cep->qp); + } + + read_unlock(&sk->sk_callback_lock); } static int siw_qp_readq_init(struct siw_qp *qp, int irq_size, int orq_size)