From: Kaike Wan <kaike.wan@xxxxxxxxx> commit c1abd865bd125015783286b353abb8da51644f59 upstream. The index r_tid_ack is used to indicate the next TID RDMA WRITE request to acknowledge in the ring s_ack_queue[] on the responder side and should be set to a valid index other than its initial value before r_tid_tail is advanced to the next TID RDMA WRITE request and particularly before a TID RDMA ACK is built. Otherwise, a NULL pointer dereference may result: BUG: unable to handle kernel paging request at ffff9a32d27abff8 IP: [<ffffffffc0d87ea6>] hfi1_make_tid_rdma_pkt+0x476/0xcb0 [hfi1] PGD 2749032067 PUD 0 Oops: 0000 1 SMP Modules linked in: osp(OE) ofd(OE) lfsck(OE) ost(OE) mgc(OE) osd_zfs(OE) lquota(OE) lustre(OE) lmv(OE) mdc(OE) lov(OE) fid(OE) fld(OE) ko2iblnd(OE) ptlrpc(OE) obdclass(OE) lnet(OE) libcfs(OE) ib_ipoib(OE) hfi1(OE) rdmavt(OE) nfsv3 nfs_acl rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace fscache ib_isert iscsi_target_mod target_core_mod ib_ucm dm_mirror dm_region_hash dm_log mlx5_ib dm_mod zfs(POE) rpcrdma sunrpc rdma_ucm ib_uverbs opa_vnic ib_iser zunicode(POE) ib_umad zavl(POE) icp(POE) sb_edac intel_powerclamp coretemp rdma_cm intel_rapl iosf_mbi iw_cm libiscsi scsi_transport_iscsi kvm ib_cm iTCO_wdt mxm_wmi iTCO_vendor_support irqbypass crc32_pclmul ghash_clmulni_intel aesni_intel lrw gf128mul glue_helper ablk_helper cryptd zcommon(POE) znvpair(POE) pcspkr spl(OE) mei_me sg mei ioatdma lpc_ich joydev i2c_i801 shpchp ipmi_si ipmi_devintf ipmi_msghandler wmi acpi_power_meter ip_tables xfs libcrc32c sd_mod crc_t10dif crct10dif_generic mgag200 mlx5_core drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ixgbe ahci ttm mlxfw ib_core libahci devlink mdio crct10dif_pclmul crct10dif_common drm ptp libata megaraid_sas crc32c_intel i2c_algo_bit pps_core i2c_core dca [last unloaded: rdmavt] CPU: 15 PID: 68691 Comm: kworker/15:2H Kdump: loaded Tainted: P W OE ------------ 3.10.0-862.2.3.el7_lustre.x86_64 #1 Hardware name: Intel Corporation S2600WTT/S2600WTT, BIOS SE5C610.86B.01.01.0016.033120161139 03/31/2016 Workqueue: hfi0_0 _hfi1_do_tid_send [hfi1] task: ffff9a01f47faf70 ti: ffff9a11776a8000 task.ti: ffff9a11776a8000 RIP: 0010:[<ffffffffc0d87ea6>] [<ffffffffc0d87ea6>] hfi1_make_tid_rdma_pkt+0x476/0xcb0 [hfi1] RSP: 0018:ffff9a11776abd08 EFLAGS: 00010002 RAX: ffff9a32d27abfc0 RBX: ffff99f2d27aa000 RCX: 00000000ffffffff RDX: 0000000000000000 RSI: 0000000000000220 RDI: ffff99f2ffc05300 RBP: ffff9a11776abd88 R08: 000000000001c310 R09: ffffffffc0d87ad4 R10: 0000000000000000 R11: 0000000000000000 R12: ffff9a117a423c00 R13: ffff9a117a423c00 R14: ffff9a03500c0000 R15: ffff9a117a423cb8 FS: 0000000000000000(0000) GS:ffff9a117e9c0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff9a32d27abff8 CR3: 0000002748a0e000 CR4: 00000000001607e0 Call Trace: [<ffffffffc0d88874>] _hfi1_do_tid_send+0x194/0x320 [hfi1] [<ffffffffaf0b2dff>] process_one_work+0x17f/0x440 [<ffffffffaf0b3ac6>] worker_thread+0x126/0x3c0 [<ffffffffaf0b39a0>] ? manage_workers.isra.24+0x2a0/0x2a0 [<ffffffffaf0bae31>] kthread+0xd1/0xe0 [<ffffffffaf0bad60>] ? insert_kthread_work+0x40/0x40 [<ffffffffaf71f5f7>] ret_from_fork_nospec_begin+0x21/0x21 [<ffffffffaf0bad60>] ? insert_kthread_work+0x40/0x40 hfi1 0000:05:00.0: hfi1_0: reserved_op: opcode 0xf2, slot 2, rsv_used 1, rsv_ops 1 Code: 00 00 41 8b 8d d8 02 00 00 89 c8 48 89 45 b0 48 c1 65 b0 06 48 8b 83 a0 01 00 00 48 01 45 b0 48 8b 45 b0 41 80 bd 10 03 00 00 00 <48> 8b 50 38 4c 8d 7a 50 74 45 8b b2 d0 00 00 00 85 f6 0f 85 72 RIP [<ffffffffc0d87ea6>] hfi1_make_tid_rdma_pkt+0x476/0xcb0 [hfi1] RSP <ffff9a11776abd08> CR2: ffff9a32d27abff8 This problem can happen if a RESYNC request is received before r_tid_ack is modified. This patch fixes the issue by making sure that r_tid_ack is set to a valid value before a TID RDMA ACK is built. Functions are defined to simplify the code. Fixes: 07b923701e38 ("IB/hfi1: Add functions to receive TID RDMA WRITE request") Fixes: 7cf0ad679de4 ("IB/hfi1: Add a function to receive TID RDMA RESYNC packet") Link: https://lore.kernel.org/r/20191025195830.106825.44022.stgit@xxxxxxxxxxxxxxxxxxxx Cc: <stable@xxxxxxxxxxxxxxx> Reviewed-by: Mike Marciniszyn <mike.marciniszyn@xxxxxxxxx> Reviewed-by: Dennis Dalessandro <dennis.dalessandro@xxxxxxxxx> Signed-off-by: Kaike Wan <kaike.wan@xxxxxxxxx> Signed-off-by: Dennis Dalessandro <dennis.dalessandro@xxxxxxxxx> Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/infiniband/hw/hfi1/tid_rdma.c | 44 ++++++++++++++++++++-------------- 1 file changed, 27 insertions(+), 17 deletions(-) --- a/drivers/infiniband/hw/hfi1/tid_rdma.c +++ b/drivers/infiniband/hw/hfi1/tid_rdma.c @@ -136,6 +136,26 @@ static void update_r_next_psn_fecn(struc struct tid_rdma_flow *flow, bool fecn); +static void validate_r_tid_ack(struct hfi1_qp_priv *priv) +{ + if (priv->r_tid_ack == HFI1_QP_WQE_INVALID) + priv->r_tid_ack = priv->r_tid_tail; +} + +static void tid_rdma_schedule_ack(struct rvt_qp *qp) +{ + struct hfi1_qp_priv *priv = qp->priv; + + priv->s_flags |= RVT_S_ACK_PENDING; + hfi1_schedule_tid_send(qp); +} + +static void tid_rdma_trigger_ack(struct rvt_qp *qp) +{ + validate_r_tid_ack(qp->priv); + tid_rdma_schedule_ack(qp); +} + static u64 tid_rdma_opfn_encode(struct tid_rdma_params *p) { return @@ -2997,10 +3017,7 @@ nak_psn: qpriv->s_nak_state = IB_NAK_PSN_ERROR; /* We are NAK'ing the next expected PSN */ qpriv->s_nak_psn = mask_psn(flow->flow_state.r_next_psn); - qpriv->s_flags |= RVT_S_ACK_PENDING; - if (qpriv->r_tid_ack == HFI1_QP_WQE_INVALID) - qpriv->r_tid_ack = qpriv->r_tid_tail; - hfi1_schedule_tid_send(qp); + tid_rdma_trigger_ack(qp); } goto unlock; } @@ -3518,7 +3535,7 @@ static void hfi1_tid_write_alloc_resourc /* * If overtaking req->acked_tail, send an RNR NAK. Because the * QP is not queued in this case, and the issue can only be - * caused due a delay in scheduling the second leg which we + * caused by a delay in scheduling the second leg which we * cannot estimate, we use a rather arbitrary RNR timeout of * (MAX_FLOWS / 2) segments */ @@ -3526,8 +3543,7 @@ static void hfi1_tid_write_alloc_resourc MAX_FLOWS)) { ret = -EAGAIN; to_seg = MAX_FLOWS >> 1; - qpriv->s_flags |= RVT_S_ACK_PENDING; - hfi1_schedule_tid_send(qp); + tid_rdma_trigger_ack(qp); break; } @@ -4327,8 +4343,7 @@ void hfi1_rc_rcv_tid_rdma_write_data(str trace_hfi1_tid_req_rcv_write_data(qp, 0, e->opcode, e->psn, e->lpsn, req); trace_hfi1_tid_write_rsp_rcv_data(qp); - if (priv->r_tid_ack == HFI1_QP_WQE_INVALID) - priv->r_tid_ack = priv->r_tid_tail; + validate_r_tid_ack(priv); if (opcode == TID_OP(WRITE_DATA_LAST)) { release_rdma_sge_mr(e); @@ -4367,8 +4382,7 @@ void hfi1_rc_rcv_tid_rdma_write_data(str } done: - priv->s_flags |= RVT_S_ACK_PENDING; - hfi1_schedule_tid_send(qp); + tid_rdma_schedule_ack(qp); exit: priv->r_next_psn_kdeth = flow->flow_state.r_next_psn; if (fecn) @@ -4380,10 +4394,7 @@ send_nak: if (!priv->s_nak_state) { priv->s_nak_state = IB_NAK_PSN_ERROR; priv->s_nak_psn = flow->flow_state.r_next_psn; - priv->s_flags |= RVT_S_ACK_PENDING; - if (priv->r_tid_ack == HFI1_QP_WQE_INVALID) - priv->r_tid_ack = priv->r_tid_tail; - hfi1_schedule_tid_send(qp); + tid_rdma_trigger_ack(qp); } goto done; } @@ -4931,8 +4942,7 @@ void hfi1_rc_rcv_tid_rdma_resync(struct qpriv->resync = true; /* RESYNC request always gets a TID RDMA ACK. */ qpriv->s_nak_state = 0; - qpriv->s_flags |= RVT_S_ACK_PENDING; - hfi1_schedule_tid_send(qp); + tid_rdma_trigger_ack(qp); bail: if (fecn) qp->s_flags |= RVT_S_ECN;