C Process finished with exit code 139 (interrupted by signal 11: SIGSEGV)

I try walk in ports.

typedef unsigned int ui;

#include "pci.h"
#include "string.h"
#include <sys/io.h>
#include <stdio.h>
#include <errno.h>

char* getBaseClassName(ui baseClassCode){//decipher Class Code field (see txt document lab3.txt) :) 
    char* str;
    switch(baseClassCode){
        case 0:
            str = "Devices, constructed before classification.";
            break;
        case 1:
            str = "Storage controllers.";
            break;
        case 2:
            str = "Network controllers";
            break;
        case 3:
            str = "Display controllers.";
            break;
        case 4:
            str = "Multimedia devices.";
            break;
        case 5:
            str = "Memory controllers.";
            break;
        case 6:
            str = "Bridges.";
            break;
        case 7:
            str = "Communication controllers.";
            break;
        case 8:
            str = "System peripherals.";
            break;
        case 9:
            str = "IO device controllers.";
            break;
        case 10:
            str = "Dock station.";
            break;
        case 11:
            str = "Processors.";
            break;
        case 12:
            str = "Serial bus controllers.";
            break;
        case 13:
            str = "Wireless interface controllers.";
            break;
    }
    return str;
}

char* getIntPinType(ui reg){//decipher Interrupt pin
    char* str;
    switch (reg) {
        case 0:
            str = "-";
            break;
        case 1:
            str = "INTA#";
            break;
        case 2:
            str = "INTB#";
            break;
        case 3:
            str = "INTC#";
            break;
        case 4:
            str = "INTD#";
            break;
        default:
            str = "Invalid Pin number";
            break;
    }
}

int main()
{
    ui address = 0x80000000, vendorId, deviceId, result, headerType, interruptPin, addressMemory, classCodeReg;
    if (iopl(3)) {
        printf("I/O Privilege level change error: %s\nTry running under ROOT user\n", strerror(errno));
        return 2;
    }
    else
    {
        printf("Access received!\n");
    }
    for(ui i = 0; i < 256; i++)//cycle for bus number
    {
        address &= 0xFF00FFFF;
        address |= i << 16;
        for(ui j = 0; j < 32; j++)//cycle for device number
        {
            address &= 0xFFFF07FF;https://www.youtube.com/watch?v=NxXX1pClpkY
            address |= j << 11;
            for(ui k = 0; k < 8; k++)//cycle for function number
            {
                address &= 0xFFFFF8FF;
                address |= k << 8;
                outl(address, 0xCF8);
                result = inl(0xCFC);
                if(result != 0xFFFFFFFF){//check if device is connected
                    printf("%d:%d:%d\n", i, j, k);
                    vendorId = result & 0x0000FFFF;
                    deviceId = (result & 0xFFFF0000) >> 16;
                    for(ui m = 0; m < PCI_VENTABLE_LEN; m++)//searching for vendorId in PciVenTable[], where PCI_VENTABLE_LEN is size of this array
                        if(vendorId == PciVenTable[m].VendorId)
                            printf("Vendor: %x -> %s\n", PciVenTable[m].VendorId, PciVenTable[m].VendorName);
                    for(ui n = 0; n < PCI_DEVTABLE_LEN; n++)//searching for deviceId in PciDevTable[], where PCI_DEVTABLE_LEN is size of this array
                        if((deviceId == PciDevTable[n].DeviceId) && (vendorId == PciDevTable[n].VendorId))
                            printf("Device: %x -> %s\n", PciDevTable[n].DeviceId, PciDevTable[n].DeviceName);
                    outl((address & 0xFFFFFF03) | 0x0000000C, 0xCF8);
                    headerType = (inl(0xCFC) & 0x0800000) >> 23;
                    if(headerType == 0){//check if device is bridge
                        printf("\nNot Bridge\n\n");
                        outl((address & 0xFFFFFF03) | 0x0000003C, 0xCF8);
                        interruptPin = (inl(0xCFC) >> 8) & 0xFF;
                        printf("Interrupt Pin: %x -> %s\n", interruptPin, getIntPinType(interruptPin));
                        ui regNum = 0x10, delta = 0x04, regType, counter = 1;//start with 0x10 address adding 0x04 to look for each register
                        printf("BARs:\n\n");
                        while(regNum != 0x28){//cycle for analyzing BAR registers (0 - Memory reg, 1 - I/O space reg)
                            outl(address & 0xFFFFFF03|regNum, 0xCF8);
                            regType = (inl(0xCFC) & 0x1);
                            outl(address & 0xFFFFFF03|regNum, 0xCF8);
                            addressMemory = inl(0xCFC);
                            printf("Reg%d: ", counter);
                            if(addressMemory == 0){
                                printf("Unused register\n");
                            }
                            else if(regType == 0){//check if memory
                                printf("Memory address register\n");
                            }
                            else if(regType == 1){//check if IO
                                printf("I/O space register: Base address - %x\n", addressMemory);
                            }
                            regNum += delta;
                            counter++;
                        }
                        outl((address & 0xFFFFFF03) | 0x08, 0xCF8);
                        classCodeReg = inl(0xCFC) >> 8;
                        ui baseClassCode = classCodeReg >> 16;
                        printf("Base class code: %x -> %s\n", baseClassCode, getBaseClassName(baseClassCode));//output number of classcode and deciphering this field
                    }
                    printf("---------------------------------\n");
                }
            }
        }
    }
    return 0;
}