scsi: lpfc: Validate ELS LS_ACC completion payload

A WCQE success completion status does not guarantee valid LS_ACC receipt
for ELS commands.  So, introduce a small helper routine that validates ELS
LS_ACC frames in ELS cmpl routines.

Signed-off-by: Justin Tee <justin.tee@broadcom.com>
Link: https://lore.kernel.org/r/20231009161812.97232-5-justintee8345@gmail.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/lpfc/lpfc_els.c b/drivers/scsi/lpfc/lpfc_els.c
index 54e47f2682358ab027ed90e5ffee0349f9fa3f9d..f9627eddab08549f5f2510108415bcf22df1ab53 100644 (file)
--- a/drivers/scsi/lpfc/lpfc_els.c
+++ b/drivers/scsi/lpfc/lpfc_els.c
@@ -131,6 +131,15 @@ lpfc_els_chk_latt(struct lpfc_vport *vport)
        return 1;
 }
 
+static bool lpfc_is_els_acc_rsp(struct lpfc_dmabuf *buf)
+{
+       struct fc_els_ls_acc *rsp = buf->virt;
+
+       if (rsp && rsp->la_cmd == ELS_LS_ACC)
+               return true;
+       return false;
+}
+
 /**
  * lpfc_prep_els_iocb - Allocate and prepare a lpfc iocb data structure
  * @vport: pointer to a host virtual N_Port data structure.
@@ -1107,6 +1116,8 @@ stop_rr_fcf_flogi:
        prsp = list_get_first(&pcmd->list, struct lpfc_dmabuf, list);
        if (!prsp)
                goto out;
+       if (!lpfc_is_els_acc_rsp(prsp))
+               goto out;
        sp = prsp->virt + sizeof(uint32_t);
 
        /* FLOGI completes successfully */
@@ -2119,6 +2130,10 @@ lpfc_cmpl_els_plogi(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                /* Good status, call state machine */
                prsp = list_entry(cmdiocb->cmd_dmabuf->list.next,
                                  struct lpfc_dmabuf, list);
+               if (!prsp)
+                       goto out;
+               if (!lpfc_is_els_acc_rsp(prsp))
+                       goto out;
                ndlp = lpfc_plogi_confirm_nport(phba, prsp->virt, ndlp);
 
                sp = (struct serv_parm *)((u8 *)prsp->virt +
@@ -3445,6 +3460,8 @@ lpfc_cmpl_els_disc_cmd(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                prdf = (struct lpfc_els_rdf_rsp *)prsp->virt;
                if (!prdf)
                        goto out;
+               if (!lpfc_is_els_acc_rsp(prsp))
+                       goto out;
 
                for (i = 0; i < ELS_RDF_REG_TAG_CNT &&
                            i < be32_to_cpu(prdf->reg_d1.reg_desc.count); i++)
@@ -4043,6 +4060,9 @@ lpfc_cmpl_els_edc(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
                        edc_rsp->acc_hdr.la_cmd,
                        be32_to_cpu(edc_rsp->desc_list_len));
 
+       if (!lpfc_is_els_acc_rsp(prsp))
+               goto out;
+
        /*
         * Payload length in bytes is the response descriptor list
         * length minus the 12 bytes of Link Service Request
@@ -11339,6 +11359,9 @@ lpfc_cmpl_els_fdisc(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
        prsp = list_get_first(&pcmd->list, struct lpfc_dmabuf, list);
        if (!prsp)
                goto out;
+       if (!lpfc_is_els_acc_rsp(prsp))
+               goto out;
+
        sp = prsp->virt + sizeof(uint32_t);
        fabric_param_changed = lpfc_check_clean_addr_bit(vport, sp);
        memcpy(&vport->fabric_portname, &sp->portName,