Re: [PATCH-for-5.2 v2] hw/core/qdev-properties-system: Rewrite set_pci_host_devaddr using GLib

[Philippe Mathieu-Daudé]

Cc'ing PCI developers (rc2 is scheduled for tomorrow).

On 11/7/20 9:59 AM, Philippe Mathieu-Daudé wrote:
> Ping for 5.2 as this is a bugfix.
> 
> On 10/13/20 12:22 PM, Philippe Mathieu-Daudé wrote:
>> set_pci_host_devaddr() is hard to follow, thus bug-prone.
>> We indeed introduced a bug in commit bccb20c49df, as the
>> same line might be used to parse a bus (up to 0xff) or a
>> slot (up to 0x1f). Instead of making things worst, rewrite
>> using g_strsplit().
>>
>> Fixes: bccb20c49df ("Use qemu_strtoul() in set_pci_host_devaddr()")
>> Reported-by: Klaus Herman <kherman@inbox.lv>
>> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
>> ---
>> v2: Free g_strsplit() with g_auto(GStrv) (Daniel)
>> ---
>>  hw/core/qdev-properties-system.c | 61 ++++++++++++++------------------
>>  1 file changed, 27 insertions(+), 34 deletions(-)
>>
>> diff --git a/hw/core/qdev-properties-system.c 
>> b/hw/core/qdev-properties-system.c
>> index 49bdd125814..36d4fd8b22a 100644
>> --- a/hw/core/qdev-properties-system.c
>> +++ b/hw/core/qdev-properties-system.c
>> @@ -878,11 +878,11 @@ static void set_pci_host_devaddr(Object *obj, Visitor 
>> *v, const char *name,
>>      DeviceState *dev = DEVICE(obj);
>>      Property *prop = opaque;
>>      PCIHostDeviceAddress *addr = qdev_get_prop_ptr(dev, prop);
>> -    char *str, *p;
>> -    const char *e;
>> +    g_autofree char *str = NULL;
>> +    g_auto(GStrv) col_s0 = NULL;
>> +    g_auto(GStrv) dot_s = NULL;
>> +    char **col_s;
>>      unsigned long val;
>> -    unsigned long dom = 0, bus = 0;
>> -    unsigned int slot = 0, func = 0;
>>  
>>      if (dev->realized) {
>>          qdev_prop_set_after_realize(dev, name, errp);
>> @@ -893,57 +893,50 @@ static void set_pci_host_devaddr(Object *obj, Visitor 
>> *v, const char *name,
>>          return;
>>      }
>>  
>> -    p = str;
>> -    if (qemu_strtoul(p, &e, 16, &val) < 0 || val > 0xffff || e == p) {
>> +    col_s = col_s0 = g_strsplit(str, ":", 3);
>> +    if (!col_s || !col_s[0] || !col_s[1]) {
>>          goto inval;
>>      }
>> -    if (*e != ':') {
>> -        goto inval;
>> -    }
>> -    bus = val;
>>  
>> -    p = (char *)e + 1;
>> -    if (qemu_strtoul(p, &e, 16, &val) < 0 || val > 0x1f || e == p) {
>> -        goto inval;
>> -    }
>> -    if (*e == ':') {
>> -        dom = bus;
>> -        bus = val;
>> -        p = (char *)e + 1;
>> -        if (qemu_strtoul(p, &e, 16, &val) < 0 || val > 0x1f || e == p) {
>> +    /* domain */
>> +    if (col_s[2]) {
>> +        if (qemu_strtoul(col_s[0], NULL, 16, &val) < 0 || val > 0xffff) {
>>              goto inval;
>>          }
>> +        addr->domain = val;
>> +        col_s++;
>> +    } else {
>> +        addr->domain = 0;
>>      }
>> -    slot = val;
>>  
>> -    if (*e != '.') {
>> +    /* bus */
>> +    if (qemu_strtoul(col_s[0], NULL, 16, &val) < 0 || val > 0xff) {
>>          goto inval;
>>      }
>> -    p = (char *)e + 1;
>> -    if (qemu_strtoul(p, &e, 10, &val) < 0 || val > 7 || e == p) {
>> -        goto inval;
>> -    }
>> -    func = val;
>> +    addr->bus = val;
>>  
>> -    if (bus > 0xff) {
>> +    /* <slot>.<func> */
>> +    dot_s = g_strsplit(col_s[1], ".", 2);
>> +    if (!dot_s || !dot_s[0] || !dot_s[1]) {
>>          goto inval;
>>      }
>>  
>> -    if (*e) {
>> +    /* slot */
>> +    if (qemu_strtoul(dot_s[0], NULL, 16, &val) < 0 || val > 0x1f) {
>>          goto inval;
>>      }
>> +    addr->slot = val;
>>  
>> -    addr->domain = dom;
>> -    addr->bus = bus;
>> -    addr->slot = slot;
>> -    addr->function = func;
>> +    /* func */
>> +    if (qemu_strtoul(dot_s[1], NULL, 10, &val) < 0 || val > 7) {
>> +        goto inval;
>> +    }
>> +    addr->function = val;
>>  
>> -    g_free(str);
>>      return;
>>  
>>  inval:
>>      error_set_from_qdev_prop_error(errp, EINVAL, dev, prop, str);
>> -    g_free(str);
>>  }
>>  
>>  const PropertyInfo qdev_prop_pci_host_devaddr = {
>>
>