Re: [Qemu-devel] [PATCH] hw/iommu: Fix problems reported by Coverity scan

[David Kiarie]

On Sat, Oct 1, 2016 at 7:29 PM, Stefan Weil <address@hidden> wrote:
> Hi,
>
>
> On 10/01/16 17:57, David Kiarie wrote:
>>
>> Signed-off-by: David Kiarie <address@hidden>
>> ---
>>  hw/i386/amd_iommu.c | 12 ++++++++----
>>  1 file changed, 8 insertions(+), 4 deletions(-)
>>
>> diff --git a/hw/i386/amd_iommu.c b/hw/i386/amd_iommu.c
>> index 023de52..815d45f 100644
>> --- a/hw/i386/amd_iommu.c
>> +++ b/hw/i386/amd_iommu.c
>> @@ -144,7 +144,7 @@ static void amdvi_assign_andq(AMDVIState *s, hwaddr
>> addr, uint64_t val)
>>  static void amdvi_generate_msi_interrupt(AMDVIState *s)
>>  {
>>      MSIMessage msg;
>> -    MemTxAttrs attrs;
>> +    MemTxAttrs attrs = {0, 0};
>>
>>      attrs.requester_id = pci_requester_id(&s->pci.dev);
>>
>> @@ -185,7 +185,7 @@ static void amdvi_setevent_bits(uint64_t *buffer,
>> uint64_t value, int start,
>>                                  int length)
>>  {
>>      int index = start / 64, bitpos = start % 64;
>> -    uint64_t mask = ((1 << length) - 1) << bitpos;
>> +    uint64_t mask = ((1UL << length) - 1) << bitpos;
>>      buffer[index] &= ~mask;
>>      buffer[index] |= (value << bitpos) & mask;
>>  }
>> @@ -334,7 +334,7 @@ static void amdvi_update_iotlb(AMDVIState *s, uint16_t
>> devid,
>>                                 uint16_t domid)
>>  {
>>      AMDVIIOTLBEntry *entry = g_malloc(sizeof(*entry));
>> -    uint64_t *key = g_malloc(sizeof(key));
>> +    uint64_t *key = g_malloc(sizeof(*key));
>
>
> I suggest using g_new(uint64_t, 1) here.
>
>>      uint64_t gfn = gpa >> AMDVI_PAGE_SHIFT_4K;
>>
>>      /* don't cache erroneous translations */
>> @@ -1135,6 +1135,7 @@ static void amdvi_reset(DeviceState *dev)
>>
>>  static void amdvi_realize(DeviceState *dev, Error **err)
>>  {
>> +    int ret = 0;
>>      AMDVIState *s = AMD_IOMMU_DEVICE(dev);
>>      X86IOMMUState *x86_iommu = X86_IOMMU_DEVICE(dev);
>>      PCIBus *bus = PC_MACHINE(qdev_get_machine())->bus;
>> @@ -1147,8 +1148,11 @@ static void amdvi_realize(DeviceState *dev, Error
>> **err)
>>      object_property_set_bool(OBJECT(&s->pci), true, "realized", err);
>>      s->capab_offset = pci_add_capability(&s->pci.dev, AMDVI_CAPAB_ID_SEC,
>> 0,
>>                                           AMDVI_CAPAB_SIZE);
>> -    pci_add_capability(&s->pci.dev, PCI_CAP_ID_MSI, 0,
>> AMDVI_CAPAB_REG_SIZE);
>> +    assert(s->capab_offset > 0);
>> +    ret = pci_add_capability(&s->pci.dev, PCI_CAP_ID_MSI, 0,
>> AMDVI_CAPAB_REG_SIZE);
>> +    assert(ret > 0);
>>      pci_add_capability(&s->pci.dev, PCI_CAP_ID_HT, 0,
>> AMDVI_CAPAB_REG_SIZE);
>
>
> Did you forget to assign the result to ret here? Without that, the following
> assertion does not make sense, and coverity will still complain.

Yeah, missed something here.

>
>
>> +    assert(ret > 0);
>>
>>      /* set up MMIO */
>>      memory_region_init_io(&s->mmio, OBJECT(s), &mmio_mem_ops, s,
>> "amdvi-mmio",
>>
>
> Stefan
>