[PATCH] qobject: Fix maybe uninitialized in qdict_array_split

[PATCH] qobject: Fix maybe uninitialized in qdict_array_split

[Janosch Frank]

Lets make the compiler happy.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
---
 qobject/block-qdict.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/qobject/block-qdict.c b/qobject/block-qdict.c
index 1487cc5dd8..b26524429c 100644
--- a/qobject/block-qdict.c
+++ b/qobject/block-qdict.c
@@ -224,7 +224,7 @@ void qdict_array_split(QDict *src, QList **dst)
     for (i = 0; i < UINT_MAX; i++) {
         QObject *subqobj;
         bool is_subqdict;
-        QDict *subqdict;
+        QDict *subqdict = NULL;
         char indexstr[32], prefix[32];
         size_t snprintf_ret;
 
-- 
2.30.2

Re: [PATCH] qobject: Fix maybe uninitialized in qdict_array_split

[Janosch Frank]

On 5/18/21 3:06 PM, Janosch Frank wrote:
> Lets make the compiler happy.
> 
> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>

Ping
My build is still breaking on Ubuntu because of this.

> ---
>  qobject/block-qdict.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/qobject/block-qdict.c b/qobject/block-qdict.c
> index 1487cc5dd8..b26524429c 100644
> --- a/qobject/block-qdict.c
> +++ b/qobject/block-qdict.c
> @@ -224,7 +224,7 @@ void qdict_array_split(QDict *src, QList **dst)
>      for (i = 0; i < UINT_MAX; i++) {
>          QObject *subqobj;
>          bool is_subqdict;
> -        QDict *subqdict;
> +        QDict *subqdict = NULL;
>          char indexstr[32], prefix[32];
>          size_t snprintf_ret;
>  
> 

Re: [PATCH] qobject: Fix maybe uninitialized in qdict_array_split

[Philippe Mathieu-Daudé]

On 5/31/21 11:21 AM, Janosch Frank wrote:
> On 5/18/21 3:06 PM, Janosch Frank wrote:
>> Lets make the compiler happy.
>>
>> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
> 
> Ping
> My build is still breaking on Ubuntu because of this.
> 
>> ---
>>  qobject/block-qdict.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/qobject/block-qdict.c b/qobject/block-qdict.c
>> index 1487cc5dd8..b26524429c 100644
>> --- a/qobject/block-qdict.c
>> +++ b/qobject/block-qdict.c
>> @@ -224,7 +224,7 @@ void qdict_array_split(QDict *src, QList **dst)
>>      for (i = 0; i < UINT_MAX; i++) {
>>          QObject *subqobj;
>>          bool is_subqdict;
>> -        QDict *subqdict;
>> +        QDict *subqdict = NULL;
>>          char indexstr[32], prefix[32];
>>          size_t snprintf_ret;

Slightly clearer:

-- >8 --
diff --git a/qobject/block-qdict.c b/qobject/block-qdict.c
index 1487cc5dd8b..8d0f00bc3ce 100644
--- a/qobject/block-qdict.c
+++ b/qobject/block-qdict.c
@@ -224,7 +224,6 @@ void qdict_array_split(QDict *src, QList **dst)
     for (i = 0; i < UINT_MAX; i++) {
         QObject *subqobj;
         bool is_subqdict;
-        QDict *subqdict;
         char indexstr[32], prefix[32];
         size_t snprintf_ret;

@@ -249,14 +248,16 @@ void qdict_array_split(QDict *src, QList **dst)
         }

         if (is_subqdict) {
+            QDict *subqdict = NULL;
+
             qdict_extract_subqdict(src, &subqdict, prefix);
             assert(qdict_size(subqdict) > 0);
+            qlist_append_obj(*dst, QOBJECT(subqdict));
         } else {
             qobject_ref(subqobj);
             qdict_del(src, indexstr);
+            qlist_append_obj(*dst, subqobj);
         }
-
-        qlist_append_obj(*dst, subqobj ?: QOBJECT(subqdict));
     }
 }
---

Anyhow,
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>

Cc'ing qemu-trivial@

Re: [PATCH] qobject: Fix maybe uninitialized in qdict_array_split

[Janosch Frank]

On 5/31/21 11:44 AM, Philippe Mathieu-Daudé wrote:
> On 5/31/21 11:21 AM, Janosch Frank wrote:
>> On 5/18/21 3:06 PM, Janosch Frank wrote:
>>> Lets make the compiler happy.
>>>
>>> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
>>
>> Ping
>> My build is still breaking on Ubuntu because of this.
>>
>>> ---
>>>  qobject/block-qdict.c | 2 +-
>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/qobject/block-qdict.c b/qobject/block-qdict.c
>>> index 1487cc5dd8..b26524429c 100644
>>> --- a/qobject/block-qdict.c
>>> +++ b/qobject/block-qdict.c
>>> @@ -224,7 +224,7 @@ void qdict_array_split(QDict *src, QList **dst)
>>>      for (i = 0; i < UINT_MAX; i++) {
>>>          QObject *subqobj;
>>>          bool is_subqdict;
>>> -        QDict *subqdict;
>>> +        QDict *subqdict = NULL;
>>>          char indexstr[32], prefix[32];
>>>          size_t snprintf_ret;
> 
> Slightly clearer:>
> -- >8 --
> diff --git a/qobject/block-qdict.c b/qobject/block-qdict.c
> index 1487cc5dd8b..8d0f00bc3ce 100644
> --- a/qobject/block-qdict.c
> +++ b/qobject/block-qdict.c
> @@ -224,7 +224,6 @@ void qdict_array_split(QDict *src, QList **dst)
>      for (i = 0; i < UINT_MAX; i++) {
>          QObject *subqobj;
>          bool is_subqdict;
> -        QDict *subqdict;
>          char indexstr[32], prefix[32];
>          size_t snprintf_ret;
> 
> @@ -249,14 +248,16 @@ void qdict_array_split(QDict *src, QList **dst)
>          }
> 
>          if (is_subqdict) {
> +            QDict *subqdict = NULL;
> +
>              qdict_extract_subqdict(src, &subqdict, prefix);
>              assert(qdict_size(subqdict) > 0);
> +            qlist_append_obj(*dst, QOBJECT(subqdict));
>          } else {
>              qobject_ref(subqobj);
>              qdict_del(src, indexstr);
> +            qlist_append_obj(*dst, subqobj);
>          }
> -
> -        qlist_append_obj(*dst, subqobj ?: QOBJECT(subqdict));
>      }
>  }
> ---

If you want post that snippet yourself, go ahead.
After all I only fixed a symptom without a closer look into the code.

> 
> Anyhow,
> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> 
> Cc'ing qemu-trivial@
> 

If not I'll take it, test on s390 and send a v2 with qemu-trivial and
you in CC.


Thanks for having a look!