> On Apr 28, 2023, at 12:53 AM, Nilesh Javali <njavali@xxxxxxxxxxx> wrote:
>
> From: Quinn Tran <qutran@xxxxxxxxxxx>
>
> System crash, where driver is accessing scsi layer's
> memory (scsi_cmnd->device->host) to search for a well known internal
> pointer (vha). The scsi_cmnd was released back to upper layer which
> could be freed, but the driver is still accessing it.
>
> 7 [ffffa8e8d2c3f8d0] page_fault at ffffffff86c010fe
> [exception RIP: __qla2x00_eh_wait_for_pending_commands+240]
> RIP: ffffffffc0642350 RSP: ffffa8e8d2c3f988 RFLAGS: 00010286
> RAX: 0000000000000165 RBX: 0000000000000002 RCX: 00000000000036d8
> RDX: 0000000000000000 RSI: ffff9c5c56535188 RDI: 0000000000000286
> RBP: ffff9c5bf7aa4a58 R8: ffff9c589aecdb70 R9: 00000000000003d1
> R10: 0000000000000001 R11: 0000000000380000 R12: ffff9c5c5392bc78
> R13: ffff9c57044ff5c0 R14: ffff9c56b5a3aa00 R15: 00000000000006db
> ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018
> 8 [ffffa8e8d2c3f9c8] qla2x00_eh_wait_for_pending_commands at ffffffffc0646dd5 [qla2xxx]
> 9 [ffffa8e8d2c3fa00] __qla2x00_async_tm_cmd at ffffffffc0658094 [qla2xxx]
>
> Remove access of freed memory. Currently the driver was checking to see if
> scsi_done was called by seeing if the sp->type has changed. Instead,
> check to see if the command has left the oustanding_cmds[] array as
> sign of scsi_done was called.
>
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Quinn Tran <qutran@xxxxxxxxxxx>
> Signed-off-by: Nilesh Javali <njavali@xxxxxxxxxxx>
> ---
> drivers/scsi/qla2xxx/qla_isr.c | 38 ++++++++--
> drivers/scsi/qla2xxx/qla_os.c | 130 ++++++++++++++++-----------------
> 2 files changed, 95 insertions(+), 73 deletions(-)
>
> diff --git a/drivers/scsi/qla2xxx/qla_isr.c b/drivers/scsi/qla2xxx/qla_isr.c
> index f3107508cf12..a07c010b0843 100644
> --- a/drivers/scsi/qla2xxx/qla_isr.c
> +++ b/drivers/scsi/qla2xxx/qla_isr.c
> @@ -1862,9 +1862,9 @@ qla2x00_process_completed_request(struct scsi_qla_host *vha,
> }
> }
>
> -srb_t *
> -qla2x00_get_sp_from_handle(scsi_qla_host_t *vha, const char *func,
> - struct req_que *req, void *iocb)
> +static srb_t *
> +qla_get_sp_from_handle(scsi_qla_host_t *vha, const char *func,
> + struct req_que *req, void *iocb, u16 *ret_index)
> {
> struct qla_hw_data *ha = vha->hw;
> sts_entry_t *pkt = iocb;
> @@ -1899,12 +1899,25 @@ qla2x00_get_sp_from_handle(scsi_qla_host_t *vha, const char *func,
> return NULL;
> }
>
> - req->outstanding_cmds[index] = NULL;
> -
> + *ret_index = index;
> qla_put_fw_resources(sp->qpair, &sp->iores);
> return sp;
> }
>
> +srb_t *
> +qla2x00_get_sp_from_handle(scsi_qla_host_t *vha, const char *func,
> + struct req_que *req, void *iocb)
> +{
> + uint16_t index;
> + srb_t *sp;
> +
> + sp = qla_get_sp_from_handle(vha, func, req, iocb, &index);
> + if (sp)
> + req->outstanding_cmds[index] = NULL;
> +
> + return sp;
> +}
> +
> static void
> qla2x00_mbx_iocb_entry(scsi_qla_host_t *vha, struct req_que *req,
> struct mbx_entry *mbx)
> @@ -3237,13 +3250,13 @@ qla2x00_status_entry(scsi_qla_host_t *vha, struct rsp_que *rsp, void *pkt)
> return;
> }
>
> - req->outstanding_cmds[handle] = NULL;
> cp = GET_CMD_SP(sp);
> if (cp == NULL) {
> ql_dbg(ql_dbg_io, vha, 0x3018,
> "Command already returned (0x%x/%p).\n",
> sts->handle, sp);
>
> + req->outstanding_cmds[handle] = NULL;
> return;
> }
>
> @@ -3514,6 +3527,9 @@ qla2x00_status_entry(scsi_qla_host_t *vha, struct rsp_que *rsp, void *pkt)
>
> if (rsp->status_srb == NULL)
> sp->done(sp, res);
> +
> + /* for io's, clearing of outstanding_cmds[handle] means scsi_done was called */
> + req->outstanding_cmds[handle] = NULL;
> }
>
> /**
> @@ -3590,6 +3606,7 @@ qla2x00_error_entry(scsi_qla_host_t *vha, struct rsp_que *rsp, sts_entry_t *pkt)
> uint16_t que = MSW(pkt->handle);
> struct req_que *req = NULL;
> int res = DID_ERROR << 16;
> + u16 index;
>
> ql_dbg(ql_dbg_async, vha, 0x502a,
> "iocb type %xh with error status %xh, handle %xh, rspq id %d\n",
> @@ -3608,7 +3625,6 @@ qla2x00_error_entry(scsi_qla_host_t *vha, struct rsp_que *rsp, sts_entry_t *pkt)
>
> switch (pkt->entry_type) {
> case NOTIFY_ACK_TYPE:
> - case STATUS_TYPE:
> case STATUS_CONT_TYPE:
> case LOGINOUT_PORT_IOCB_TYPE:
> case CT_IOCB_TYPE:
> @@ -3628,6 +3644,14 @@ qla2x00_error_entry(scsi_qla_host_t *vha, struct rsp_que *rsp, sts_entry_t *pkt)
> case CTIO_TYPE7:
> case CTIO_CRC2:
> return 1;
> + case STATUS_TYPE:
> + sp = qla_get_sp_from_handle(vha, func, req, pkt, &index);
> + if (sp) {
> + sp->done(sp, res);
> + req->outstanding_cmds[index] = NULL;
> + return 0;
> + }
> + break;
> }
> fatal:
> ql_log(ql_log_warn, vha, 0x5030,
> diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
> index d0cdbfe771a9..60734c569401 100644
> --- a/drivers/scsi/qla2xxx/qla_os.c
> +++ b/drivers/scsi/qla2xxx/qla_os.c
> @@ -1078,43 +1078,6 @@ qla2xxx_mqueuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd,
> return 0;
> }
>
> -/*
> - * qla2x00_eh_wait_on_command
> - * Waits for the command to be returned by the Firmware for some
> - * max time.
> - *
> - * Input:
> - * cmd = Scsi Command to wait on.
> - *
> - * Return:
> - * Completed in time : QLA_SUCCESS
> - * Did not complete in time : QLA_FUNCTION_FAILED
> - */
> -static int
> -qla2x00_eh_wait_on_command(struct scsi_cmnd *cmd)
> -{
> -#define ABORT_POLLING_PERIOD 1000
> -#define ABORT_WAIT_ITER ((2 * 1000) / (ABORT_POLLING_PERIOD))
> - unsigned long wait_iter = ABORT_WAIT_ITER;
> - scsi_qla_host_t *vha = shost_priv(cmd->device->host);
> - struct qla_hw_data *ha = vha->hw;
> - srb_t *sp = scsi_cmd_priv(cmd);
> - int ret = QLA_SUCCESS;
> -
> - if (unlikely(pci_channel_offline(ha->pdev)) || ha->flags.eeh_busy) {
> - ql_dbg(ql_dbg_taskm, vha, 0x8005,
> - "Return:eh_wait.\n");
> - return ret;
> - }
> -
> - while (sp->type && wait_iter--)
> - msleep(ABORT_POLLING_PERIOD);
> - if (sp->type)
> - ret = QLA_FUNCTION_FAILED;
> -
> - return ret;
> -}
> -
> /*
> * qla2x00_wait_for_hba_online
> * Wait till the HBA is online after going through
> @@ -1365,6 +1328,9 @@ qla2xxx_eh_abort(struct scsi_cmnd *cmd)
> return ret;
> }
>
> +#define ABORT_POLLING_PERIOD 1000
> +#define ABORT_WAIT_ITER ((2 * 1000) / (ABORT_POLLING_PERIOD))
> +
> /*
> * Returns: QLA_SUCCESS or QLA_FUNCTION_FAILED.
> */
> @@ -1378,41 +1344,73 @@ __qla2x00_eh_wait_for_pending_commands(struct qla_qpair *qpair, unsigned int t,
> struct req_que *req = qpair->req;
> srb_t *sp;
> struct scsi_cmnd *cmd;
> + unsigned long wait_iter = ABORT_WAIT_ITER;
> + bool found;
> + struct qla_hw_data *ha = vha->hw;
>
> status = QLA_SUCCESS;
>
> - spin_lock_irqsave(qpair->qp_lock_ptr, flags);
> - for (cnt = 1; status == QLA_SUCCESS &&
> - cnt < req->num_outstanding_cmds; cnt++) {
> - sp = req->outstanding_cmds[cnt];
> - if (!sp)
> - continue;
> - if (sp->type != SRB_SCSI_CMD)
> - continue;
> - if (vha->vp_idx != sp->vha->vp_idx)
> - continue;
> - match = 0;
> - cmd = GET_CMD_SP(sp);
> - switch (type) {
> - case WAIT_HOST:
> - match = 1;
> - break;
> - case WAIT_TARGET:
> - match = cmd->device->id == t;
> - break;
> - case WAIT_LUN:
> - match = (cmd->device->id == t &&
> - cmd->device->lun == l);
> - break;
> - }
> - if (!match)
> - continue;
> + while (wait_iter--) {
> + found = false;
>
> - spin_unlock_irqrestore(qpair->qp_lock_ptr, flags);
> - status = qla2x00_eh_wait_on_command(cmd);
> spin_lock_irqsave(qpair->qp_lock_ptr, flags);
> + for (cnt = 1; cnt < req->num_outstanding_cmds; cnt++) {
> + sp = req->outstanding_cmds[cnt];
> + if (!sp)
> + continue;
> + if (sp->type != SRB_SCSI_CMD)
> + continue;
> + if (vha->vp_idx != sp->vha->vp_idx)
> + continue;
> + match = 0;
> + cmd = GET_CMD_SP(sp);
> + switch (type) {
> + case WAIT_HOST:
> + match = 1;
> + break;
> + case WAIT_TARGET:
> + if (sp->fcport)
> + match = sp->fcport->d_id.b24 == t;
> + else
> + match = 0;
> + break;
> + case WAIT_LUN:
> + if (sp->fcport)
> + match = (sp->fcport->d_id.b24 == t &&
> + cmd->device->lun == l);
> + else
> + match = 0;
> + break;
> + }
> + if (!match)
> + continue;
> +
> + spin_unlock_irqrestore(qpair->qp_lock_ptr, flags);
> +
> + if (unlikely(pci_channel_offline(ha->pdev)) ||
> + ha->flags.eeh_busy) {
> + ql_dbg(ql_dbg_taskm, vha, 0x8005,
> + "Return:eh_wait.\n");
> + return status;
> + }
> +
> + /*
> + * SRB_SCSI_CMD is still in the outstanding_cmds array.
> + * it means scsi_done has not called. Wait for it to
> + * clear from outstanding_cmds.
> + */
> + msleep(ABORT_POLLING_PERIOD);
> + spin_lock_irqsave(qpair->qp_lock_ptr, flags);
> + found = true;
> + }
> + spin_unlock_irqrestore(qpair->qp_lock_ptr, flags);
> +
> + if (!found)
> + break;
> }
> - spin_unlock_irqrestore(qpair->qp_lock_ptr, flags);
> +
> + if (!wait_iter && found)
> + status = QLA_FUNCTION_FAILED;
>
> return status;
> }
> --
> 2.23.1
>
Reviewed-by: Himanshu Madhani <himanshu.madhani@xxxxxxxxxx>
--
Himanshu Madhani Oracle Linux Engineering
