From patchwork Tue Sep 6 13:01:39 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: liuyacan@corp.netease.com X-Patchwork-Id: 12967469 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4D359ECAAD5 for ; Tue, 6 Sep 2022 13:02:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239751AbiIFNCI (ORCPT ); Tue, 6 Sep 2022 09:02:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60112 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239912AbiIFNCF (ORCPT ); Tue, 6 Sep 2022 09:02:05 -0400 Received: from corp-front07-corp.i.nease.net (corp-front07-corp.i.nease.net [59.111.134.157]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 151713E762; Tue, 6 Sep 2022 06:02:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=corp.netease.com; s=s210401; h=Received:From:To:Cc:Subject: Date:Message-Id:MIME-Version:Content-Transfer-Encoding; bh=HN2Mc O4xu5s1yDc9quFJmm947U7zeu6eeNVixn18oFU=; b=fgWu9iEHOPYQpSW0lemeU s2jQpFHrwCbs3gR6OCm+K/BoMLFI6ZnqQBlqCKio0Bzsumn81b6fh7kB/NXtSOCu FKh5hUI423jn46YE3xRXeep50a/LE5hnJhmyssGqlV85BUSy7UIqdsGSUKGNs43A IREOIwGspe60vWIMMICAcQ= Received: from pubt1-k8s74.yq.163.org (unknown [115.238.122.38]) by corp-front07-corp.i.nease.net (Coremail) with SMTP id nRDICgCX6+e1RBdj_dYXAA--.49705S2; Tue, 06 Sep 2022 21:01:41 +0800 (HKT) From: liuyacan@corp.netease.com To: wenjia@linux.ibm.com, davem@davemloft.net, edumazet@google.com, kgraul@linux.ibm.com, kuba@kernel.org Cc: tonylu@linux.alibaba.com, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, liuyacan@corp.netease.com, netdev@vger.kernel.org, pabeni@redhat.com, ubraun@linux.vnet.ibm.com, wintera@linux.ibm.com Subject: [PATCH net v5] net/smc: Fix possible access to freed memory in link clear Date: Tue, 6 Sep 2022 21:01:39 +0800 Message-Id: <20220906130139.830513-1-liuyacan@corp.netease.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 X-CM-TRANSID: nRDICgCX6+e1RBdj_dYXAA--.49705S2 X-Coremail-Antispam: 1UD129KBjvJXoW3ArWUKF15AF18XFy8Gw1kGrg_yoW7trWDpF 47Jr17Cr48Xr1DXF1kCr18Zwn8t3ZFkF1rGrnF9r1rAFn8Gw18tr1Sqry2vFWDJF4qqa4I vw48Jw1xKrs8XaUanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUULYb7IF0VCFI7km07C26c804VAKzcIF0wAFF20E14v26r4j6ryU M7CY07I20VC2zVCF04k26cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2 IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84AC jcxK6xIIjxv20xvEc7CjxVAFwI0_Cr1j6rxdM28EF7xvwVC2z280aVAFwI0_GcCE3s1l84 ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s0DM2kK67ZEXf0FJ3sC6x9vy-n0Xa0_Xr1Utr1k JwI_Jr4ln4vE4IxY62xKV4CY8xCE548m6r4UJryUGwAS0I0E0xvYzxvE52x082IY62kv04 87Mc804VCqF7xvr2I5Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWU JVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0Y48IcxkI7V AKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2kIc2xKxwAKzVCY 07xG64k0F24l7I0Y64k_MxkI7II2jI8vz4vEwIxGrwCF04k20xvY0x0EwIxGrwCF72vEw2 IIxxk0rwCFx2IqxVCFs4IE7xkEbVWUJVW8JwCFI7vE0wC20s026c02F40E14v26r1j6r18 MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr4 1lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1l IxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4 A2jsIEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0pRp6wAUUUUU= X-CM-SenderInfo: 5olx5txfdqquhrush05hwht23hof0z/1tbiBQABCVt7717U9AAJs1 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Yacan Liu After modifying the QP to the Error state, all RX WR would be completed with WC in IB_WC_WR_FLUSH_ERR status. Current implementation does not wait for it is done, but destroy the QP and free the link group directly. So there is a risk that accessing the freed memory in tasklet context. Here is a crash example: BUG: unable to handle page fault for address: ffffffff8f220860 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD f7300e067 P4D f7300e067 PUD f7300f063 PMD 8c4e45063 PTE 800ffff08c9df060 Oops: 0002 [#1] SMP PTI CPU: 1 PID: 0 Comm: swapper/1 Kdump: loaded Tainted: G S OE 5.10.0-0607+ #23 Hardware name: Inspur NF5280M4/YZMB-00689-101, BIOS 4.1.20 07/09/2018 RIP: 0010:native_queued_spin_lock_slowpath+0x176/0x1b0 Code: f3 90 48 8b 32 48 85 f6 74 f6 eb d5 c1 ee 12 83 e0 03 83 ee 01 48 c1 e0 05 48 63 f6 48 05 00 c8 02 00 48 03 04 f5 00 09 98 8e <48> 89 10 8b 42 08 85 c0 75 09 f3 90 8b 42 08 85 c0 74 f7 48 8b 32 RSP: 0018:ffffb3b6c001ebd8 EFLAGS: 00010086 RAX: ffffffff8f220860 RBX: 0000000000000246 RCX: 0000000000080000 RDX: ffff91db1f86c800 RSI: 000000000000173c RDI: ffff91db62bace00 RBP: ffff91db62bacc00 R08: 0000000000000000 R09: c00000010000028b R10: 0000000000055198 R11: ffffb3b6c001ea58 R12: ffff91db80e05010 R13: 000000000000000a R14: 0000000000000006 R15: 0000000000000040 FS: 0000000000000000(0000) GS:ffff91db1f840000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffff8f220860 CR3: 00000001f9580004 CR4: 00000000003706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: _raw_spin_lock_irqsave+0x30/0x40 mlx5_ib_poll_cq+0x4c/0xc50 [mlx5_ib] smc_wr_rx_tasklet_fn+0x56/0xa0 [smc] tasklet_action_common.isra.21+0x66/0x100 __do_softirq+0xd5/0x29c asm_call_irq_on_stack+0x12/0x20 do_softirq_own_stack+0x37/0x40 irq_exit_rcu+0x9d/0xa0 sysvec_call_function_single+0x34/0x80 asm_sysvec_call_function_single+0x12/0x20 Fixes: bd4ad57718cc ("smc: initialize IB transport incl. PD, MR, QP, CQ, event, WR") Signed-off-by: Yacan Liu Reviewed-by: Tony Lu --- Change in v5: -- Move smc_wr_drain_cq() into smc_wr_free_link() Chagen in v4: -- Remove the rx_drain flag because smc_wr_rx_post() may not have been called. -- Remove timeout. Change in v3: -- Tune commit message (Signed-Off tag, Fixes tag). Tune code to avoid column length exceeding. Change in v2: -- Fix some compile warnings and errors. --- net/smc/smc_core.c | 1 + net/smc/smc_core.h | 2 ++ net/smc/smc_wr.c | 5 +++++ net/smc/smc_wr.h | 5 +++++ 4 files changed, 13 insertions(+) diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c index ff49a11f5..ebf56cdf1 100644 --- a/net/smc/smc_core.c +++ b/net/smc/smc_core.c @@ -757,6 +757,7 @@ int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk, lnk->lgr = lgr; smc_lgr_hold(lgr); /* lgr_put in smcr_link_clear() */ lnk->link_idx = link_idx; + lnk->wr_rx_id_compl = 0; smc_ibdev_cnt_inc(lnk); smcr_copy_dev_info_to_link(lnk); atomic_set(&lnk->conn_cnt, 0); diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h index fe8b524ad..285f9bd8e 100644 --- a/net/smc/smc_core.h +++ b/net/smc/smc_core.h @@ -115,8 +115,10 @@ struct smc_link { dma_addr_t wr_rx_dma_addr; /* DMA address of wr_rx_bufs */ dma_addr_t wr_rx_v2_dma_addr; /* DMA address of v2 rx buf*/ u64 wr_rx_id; /* seq # of last recv WR */ + u64 wr_rx_id_compl; /* seq # of last completed WR */ u32 wr_rx_cnt; /* number of WR recv buffers */ unsigned long wr_rx_tstamp; /* jiffies when last buf rx */ + wait_queue_head_t wr_rx_empty_wait; /* wait for RQ empty */ struct ib_reg_wr wr_reg; /* WR register memory region */ wait_queue_head_t wr_reg_wait; /* wait for wr_reg result */ diff --git a/net/smc/smc_wr.c b/net/smc/smc_wr.c index 26f8f240d..b0678a417 100644 --- a/net/smc/smc_wr.c +++ b/net/smc/smc_wr.c @@ -454,6 +454,7 @@ static inline void smc_wr_rx_process_cqes(struct ib_wc wc[], int num) for (i = 0; i < num; i++) { link = wc[i].qp->qp_context; + link->wr_rx_id_compl = wc[i].wr_id; if (wc[i].status == IB_WC_SUCCESS) { link->wr_rx_tstamp = jiffies; smc_wr_rx_demultiplex(&wc[i]); @@ -465,6 +466,8 @@ static inline void smc_wr_rx_process_cqes(struct ib_wc wc[], int num) case IB_WC_RNR_RETRY_EXC_ERR: case IB_WC_WR_FLUSH_ERR: smcr_link_down_cond_sched(link); + if (link->wr_rx_id_compl == link->wr_rx_id) + wake_up(&link->wr_rx_empty_wait); break; default: smc_wr_rx_post(link); /* refill WR RX */ @@ -639,6 +642,7 @@ void smc_wr_free_link(struct smc_link *lnk) return; ibdev = lnk->smcibdev->ibdev; + smc_wr_drain_cq(lnk); smc_wr_wakeup_reg_wait(lnk); smc_wr_wakeup_tx_wait(lnk); @@ -889,6 +893,7 @@ int smc_wr_create_link(struct smc_link *lnk) atomic_set(&lnk->wr_tx_refcnt, 0); init_waitqueue_head(&lnk->wr_reg_wait); atomic_set(&lnk->wr_reg_refcnt, 0); + init_waitqueue_head(&lnk->wr_rx_empty_wait); return rc; dma_unmap: diff --git a/net/smc/smc_wr.h b/net/smc/smc_wr.h index a54e90a11..45e9b894d 100644 --- a/net/smc/smc_wr.h +++ b/net/smc/smc_wr.h @@ -73,6 +73,11 @@ static inline void smc_wr_tx_link_put(struct smc_link *link) wake_up_all(&link->wr_tx_wait); } +static inline void smc_wr_drain_cq(struct smc_link *lnk) +{ + wait_event(lnk->wr_rx_empty_wait, lnk->wr_rx_id_compl == lnk->wr_rx_id); +} + static inline void smc_wr_wakeup_tx_wait(struct smc_link *lnk) { wake_up_all(&lnk->wr_tx_wait);