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>
---
 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..e6e081efd58 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_autofree char **col_s0 = NULL;
+    g_autofree char **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 = {
-- 
2.26.2

On Tue, Oct 13, 2020 at 12:03:15PM +0200, 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>
> ---
>  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..e6e081efd58 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_autofree char **col_s0 = NULL;
> +    g_autofree char **dot_s = NULL;

These free the array, but not the array elements.

You need to use

   g_auto(GStrv) col_s0 = NULL

GStrv is a typedef for char **, that exists solely so that there is
a typename against which g_auto can be used.

> +    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 = {
> -- 
> 2.26.2
> 

Regards,
Daniel
-- 
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On 10/13/20 12:07 PM, Daniel P. Berrangé wrote:
> On Tue, Oct 13, 2020 at 12:03:15PM +0200, 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>
>> ---
>>   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..e6e081efd58 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_autofree char **col_s0 = NULL;
>> +    g_autofree char **dot_s = NULL;
> 
> These free the array, but not the array elements.
> 
> You need to use
> 
>     g_auto(GStrv) col_s0 = NULL
> 
> GStrv is a typedef for char **, that exists solely so that there is
> a typename against which g_auto can be used.

Ah I have been wondering how that part works.

Thanks, I'll fix.

> 
>> +    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 = {
>> -- 
>> 2.26.2
>>
> 
> Regards,
> Daniel
>