[SCSI] lpfc 8.3.45: Fix sysfs buffer overrun in read of lpfc_fcp_cpu_map for 128 CPUs.

Signed-off-by: James Smart <james.smart@emulex.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

drivers/scsi/lpfc/lpfc_attr.c

@@ -4288,7 +4288,7 @@ lpfc_fcp_cpu_map_show(struct device *dev, struct device_attribute *attr,
 	struct lpfc_vport *vport = (struct lpfc_vport *)shost->hostdata;
 	struct lpfc_hba   *phba = vport->phba;
 	struct lpfc_vector_map_info *cpup;
-	int  idx, len = 0;
+	int  len = 0;
 
 	if ((phba->sli_rev != LPFC_SLI_REV4) ||
 	    (phba->intr_type != MSIX))
@@ -4316,23 +4316,39 @@ lpfc_fcp_cpu_map_show(struct device *dev, struct device_attribute *attr,
 		break;
 	}
 
-	cpup = phba->sli4_hba.cpu_map;
-	for (idx = 0; idx < phba->sli4_hba.num_present_cpu; idx++) {
+	while (phba->sli4_hba.curr_disp_cpu < phba->sli4_hba.num_present_cpu) {
+		cpup = &phba->sli4_hba.cpu_map[phba->sli4_hba.curr_disp_cpu];
+
+		/* margin should fit in this and the truncated message */
 		if (cpup->irq == LPFC_VECTOR_MAP_EMPTY)
 			len += snprintf(buf + len, PAGE_SIZE-len,
 					"CPU %02d io_chan %02d "
 					"physid %d coreid %d\n",
-					idx, cpup->channel_id, cpup->phys_id,
+					phba->sli4_hba.curr_disp_cpu,
+					cpup->channel_id, cpup->phys_id,
 					cpup->core_id);
 		else
 			len += snprintf(buf + len, PAGE_SIZE-len,
 					"CPU %02d io_chan %02d "
 					"physid %d coreid %d IRQ %d\n",
-					idx, cpup->channel_id, cpup->phys_id,
+					phba->sli4_hba.curr_disp_cpu,
+					cpup->channel_id, cpup->phys_id,
 					cpup->core_id, cpup->irq);
 
-		cpup++;
+		phba->sli4_hba.curr_disp_cpu++;
+
+		/* display max number of CPUs keeping some margin */
+		if (phba->sli4_hba.curr_disp_cpu <
+				phba->sli4_hba.num_present_cpu &&
+				(len >= (PAGE_SIZE - 64))) {
+			len += snprintf(buf + len, PAGE_SIZE-len, "more...\n");
+			break;
+		}
 	}
+
+	if (phba->sli4_hba.curr_disp_cpu == phba->sli4_hba.num_present_cpu)
+		phba->sli4_hba.curr_disp_cpu = 0;
+
 	return len;
 }
 

drivers/scsi/lpfc/lpfc_init.c

@@ -5280,6 +5280,7 @@ lpfc_sli4_driver_resource_unset(struct lpfc_hba *phba)
 	kfree(phba->sli4_hba.cpu_map);
 	phba->sli4_hba.num_present_cpu = 0;
 	phba->sli4_hba.num_online_cpu = 0;
+	phba->sli4_hba.curr_disp_cpu = 0;
 
 	/* Free memory allocated for msi-x interrupt vector entries */
 	kfree(phba->sli4_hba.msix_entries);
@@ -6850,6 +6851,7 @@ lpfc_sli4_queue_verify(struct lpfc_hba *phba)
 	}
 	phba->sli4_hba.num_online_cpu = i;
 	phba->sli4_hba.num_present_cpu = lpfc_present_cpu;
+	phba->sli4_hba.curr_disp_cpu = 0;
 
 	if (i < cfg_fcp_io_channel) {
 		lpfc_printf_log(phba,

drivers/scsi/lpfc/lpfc_sli4.h

@@ -607,6 +607,7 @@ struct lpfc_sli4_hba {
 	struct lpfc_vector_map_info *cpu_map;
 	uint16_t num_online_cpu;
 	uint16_t num_present_cpu;
+	uint16_t curr_disp_cpu;
 };
 
 enum lpfc_sge_type {