crypto: qat - use proper type for vf_mask

Replace vf_mask type with unsigned long to avoid a stack-out-of-bound.

This is to fix the following warning reported by KASAN the first time
adf_msix_isr_ae() gets called.

    [  692.091987] BUG: KASAN: stack-out-of-bounds in find_first_bit+0x28/0x50
    [  692.092017] Read of size 8 at addr ffff88afdf789e60 by task swapper/32/0
    [  692.092076] Call Trace:
    [  692.092089]  <IRQ>
    [  692.092101]  dump_stack+0x9c/0xcf
    [  692.092132]  print_address_description.constprop.0+0x18/0x130
    [  692.092164]  ? find_first_bit+0x28/0x50
    [  692.092185]  kasan_report.cold+0x7f/0x111
    [  692.092213]  ? static_obj+0x10/0x80
    [  692.092234]  ? find_first_bit+0x28/0x50
    [  692.092262]  find_first_bit+0x28/0x50
    [  692.092288]  adf_msix_isr_ae+0x16e/0x230 [intel_qat]

Fixes: ed8ccaef ("crypto: qat - Add support for SRIOV")
Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Reviewed-by: Marco Chiappero <marco.chiappero@intel.com>
Reviewed-by: Fiona Trahe <fiona.trahe@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/qat/qat_common/adf_isr.c

@@ -15,6 +15,8 @@
 #include "adf_transport_access_macros.h"
 #include "adf_transport_internal.h"
 
+#define ADF_MAX_NUM_VFS	32
+
 static int adf_enable_msix(struct adf_accel_dev *accel_dev)
 {
 	struct adf_accel_pci *pci_dev_info = &accel_dev->accel_pci_dev;
@@ -72,7 +74,7 @@ static irqreturn_t adf_msix_isr_ae(int irq, void *dev_ptr)
 		struct adf_bar *pmisc =
 			&GET_BARS(accel_dev)[hw_data->get_misc_bar_id(hw_data)];
 		void __iomem *pmisc_bar_addr = pmisc->virt_addr;
-		u32 vf_mask;
+		unsigned long vf_mask;
 
 		/* Get the interrupt sources triggered by VFs */
 		vf_mask = ((ADF_CSR_RD(pmisc_bar_addr, ADF_ERRSOU5) &
@@ -93,8 +95,7 @@ static irqreturn_t adf_msix_isr_ae(int irq, void *dev_ptr)
 			 * unless the VF is malicious and is attempting to
 			 * flood the host OS with VF2PF interrupts.
 			 */
-			for_each_set_bit(i, (const unsigned long *)&vf_mask,
-					 (sizeof(vf_mask) * BITS_PER_BYTE)) {
+			for_each_set_bit(i, &vf_mask, ADF_MAX_NUM_VFS) {
 				vf_info = accel_dev->pf.vf_info + i;
 
 				if (!__ratelimit(&vf_info->vf2pf_ratelimit)) {