scsi: lpfc: Validate hdwq pointers before dereferencing in reset/errata paths

When the HBA is undergoing a reset or is handling an errata event, NULL ptr
dereference crashes may occur in routines such as
lpfc_sli_flush_io_rings(), lpfc_dev_loss_tmo_callbk(), or
lpfc_abort_handler().

Add NULL ptr checks before dereferencing hdwq pointers that may have been
freed due to operations colliding with a reset or errata event handler.

Signed-off-by: Justin Tee <justin.tee@broadcom.com>
Link: https://lore.kernel.org/r/20240726231512.92867-4-justintee8345@gmail.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/lpfc/lpfc_hbadisc.c b/drivers/scsi/lpfc/lpfc_hbadisc.c
index 6943f6c6395c41bbbc68c203a3e601da6ff6fd3f..f21c5993e8d72ea44fab876c7134458ec5465865 100644 (file)
--- a/drivers/scsi/lpfc/lpfc_hbadisc.c
+++ b/drivers/scsi/lpfc/lpfc_hbadisc.c
@@ -175,7 +175,8 @@ lpfc_dev_loss_tmo_callbk(struct fc_rport *rport)
                         ndlp->nlp_state, ndlp->fc4_xpt_flags);
 
        /* Don't schedule a worker thread event if the vport is going down. */
-       if (test_bit(FC_UNLOADING, &vport->load_flag)) {
+       if (test_bit(FC_UNLOADING, &vport->load_flag) ||
+           !test_bit(HBA_SETUP, &phba->hba_flag)) {
                spin_lock_irqsave(&ndlp->lock, iflags);
                ndlp->rport = NULL;
 

diff --git a/drivers/scsi/lpfc/lpfc_scsi.c b/drivers/scsi/lpfc/lpfc_scsi.c
index 98ce9d97a225703fdd060d35b27151795aa9e17d..60cd60ebff38eb3d886dbcd84ad68426b6533965 100644 (file)
--- a/drivers/scsi/lpfc/lpfc_scsi.c
+++ b/drivers/scsi/lpfc/lpfc_scsi.c
@@ -5555,11 +5555,20 @@ lpfc_abort_handler(struct scsi_cmnd *cmnd)
 
        iocb = &lpfc_cmd->cur_iocbq;
        if (phba->sli_rev == LPFC_SLI_REV4) {
-               pring_s4 = phba->sli4_hba.hdwq[iocb->hba_wqidx].io_wq->pring;
-               if (!pring_s4) {
+               /* if the io_wq & pring are gone, the port was reset. */
+               if (!phba->sli4_hba.hdwq[iocb->hba_wqidx].io_wq ||
+                   !phba->sli4_hba.hdwq[iocb->hba_wqidx].io_wq->pring) {
+                       lpfc_printf_vlog(vport, KERN_WARNING, LOG_FCP,
+                                        "2877 SCSI Layer I/O Abort Request "
+                                        "IO CMPL Status x%x ID %d LUN %llu "
+                                        "HBA_SETUP %d\n", FAILED,
+                                        cmnd->device->id,
+                                        (u64)cmnd->device->lun,
+                                        test_bit(HBA_SETUP, &phba->hba_flag));
                        ret = FAILED;
                        goto out_unlock_hba;
                }
+               pring_s4 = phba->sli4_hba.hdwq[iocb->hba_wqidx].io_wq->pring;
                spin_lock(&pring_s4->ring_lock);
        }
        /* the command is in process of being cancelled */

diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c
index d240bbded4c8f1df9b277f935e0ea92b2c4862d9..332b8d2348e9ee3d1b1de68bc1a83359603d6c36 100644 (file)
--- a/drivers/scsi/lpfc/lpfc_sli.c
+++ b/drivers/scsi/lpfc/lpfc_sli.c
@@ -4687,6 +4687,17 @@ lpfc_sli_flush_io_rings(struct lpfc_hba *phba)
        /* Look on all the FCP Rings for the iotag */
        if (phba->sli_rev >= LPFC_SLI_REV4) {
                for (i = 0; i < phba->cfg_hdw_queue; i++) {
+                       if (!phba->sli4_hba.hdwq ||
+                           !phba->sli4_hba.hdwq[i].io_wq) {
+                               lpfc_printf_log(phba, KERN_ERR, LOG_SLI,
+                                               "7777 hdwq's deleted %lx "
+                                               "%lx %x %x\n",
+                                               phba->pport->load_flag,
+                                               phba->hba_flag,
+                                               phba->link_state,
+                                               phba->sli.sli_flag);
+                               return;
+                       }
                        pring = phba->sli4_hba.hdwq[i].io_wq->pring;
 
                        spin_lock_irq(&pring->ring_lock);