diff mbox series

[04/15] ath10k: fix gcc-10 zero-length-bounds warnings

Message ID 20200430213101.135134-5-arnd@arndb.de (mailing list archive)
State New, archived
Headers show
Series gcc-10 warning fixes | expand

Commit Message

Arnd Bergmann April 30, 2020, 9:30 p.m. UTC
gcc-10 started warning about out-of-bounds access for zero-length
arrays:

In file included from drivers/net/wireless/ath/ath10k/core.h:18,
                 from drivers/net/wireless/ath/ath10k/htt_rx.c:8:
drivers/net/wireless/ath/ath10k/htt_rx.c: In function 'ath10k_htt_rx_tx_fetch_ind':
drivers/net/wireless/ath/ath10k/htt.h:1683:17: warning: array subscript 65535 is outside the bounds of an interior zero-length array 'struct htt_tx_fetch_record[0]' [-Wzero-length-bounds]
 1683 |  return (void *)&ind->records[le16_to_cpu(ind->num_records)];
      |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/net/wireless/ath/ath10k/htt.h:1676:29: note: while referencing 'records'
 1676 |  struct htt_tx_fetch_record records[0];
      |                             ^~~~~~~

The structure was already converted to have a flexible-array member in
the past, but there are two zero-length members in the end and only
one of them can be a flexible-array member.

Swap the two around to avoid the warning, as 'resp_ids' is not accessed
in a way that causes a warning.

Fixes: 3ba225b506a2 ("treewide: Replace zero-length array with flexible-array member")
Fixes: 22e6b3bc5d96 ("ath10k: add new htt definitions")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/net/wireless/ath/ath10k/htt.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Arnd Bergmann April 30, 2020, 9:44 p.m. UTC | #1
On Thu, Apr 30, 2020 at 11:41 PM Gustavo A. R. Silva
<gustavo@embeddedor.com> wrote:
> On 4/30/20 16:30, Arnd Bergmann wrote:
> > gcc-10 started warning about out-of-bounds access for zero-length
> > arrays:
> The treewide patch is an experimental change and, as this change only applies
> to my -next tree, I will carry this patch in it, so other people don't have
> to worry about this at all.

Ok, thanks!

       Arnd
Gustavo A. R. Silva April 30, 2020, 9:45 p.m. UTC | #2
Hi Arnd,

On 4/30/20 16:30, Arnd Bergmann wrote:
> gcc-10 started warning about out-of-bounds access for zero-length
> arrays:
> 
> In file included from drivers/net/wireless/ath/ath10k/core.h:18,
>                  from drivers/net/wireless/ath/ath10k/htt_rx.c:8:
> drivers/net/wireless/ath/ath10k/htt_rx.c: In function 'ath10k_htt_rx_tx_fetch_ind':
> drivers/net/wireless/ath/ath10k/htt.h:1683:17: warning: array subscript 65535 is outside the bounds of an interior zero-length array 'struct htt_tx_fetch_record[0]' [-Wzero-length-bounds]
>  1683 |  return (void *)&ind->records[le16_to_cpu(ind->num_records)];
>       |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/net/wireless/ath/ath10k/htt.h:1676:29: note: while referencing 'records'
>  1676 |  struct htt_tx_fetch_record records[0];
>       |                             ^~~~~~~
> 
> The structure was already converted to have a flexible-array member in
> the past, but there are two zero-length members in the end and only
> one of them can be a flexible-array member.
> 
> Swap the two around to avoid the warning, as 'resp_ids' is not accessed
> in a way that causes a warning.
> 
> Fixes: 3ba225b506a2 ("treewide: Replace zero-length array with flexible-array member")
> Fixes: 22e6b3bc5d96 ("ath10k: add new htt definitions")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
>  drivers/net/wireless/ath/ath10k/htt.h | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/wireless/ath/ath10k/htt.h b/drivers/net/wireless/ath/ath10k/htt.h
> index e7096a73c6ca..7621f0a3dc77 100644
> --- a/drivers/net/wireless/ath/ath10k/htt.h
> +++ b/drivers/net/wireless/ath/ath10k/htt.h
> @@ -1673,8 +1673,8 @@ struct htt_tx_fetch_ind {
>  	__le32 token;
>  	__le16 num_resp_ids;
>  	__le16 num_records;
> -	struct htt_tx_fetch_record records[0];
> -	__le32 resp_ids[]; /* ath10k_htt_get_tx_fetch_ind_resp_ids() */
> +	__le32 resp_ids[0]; /* ath10k_htt_get_tx_fetch_ind_resp_ids() */
> +	struct htt_tx_fetch_record records[];
>  } __packed;
>  
>  static inline void *
> 

The treewide patch is an experimental change and, as this change only applies
to my -next tree, I will carry this patch in it, so other people don't have
to worry about this at all.

Thank you
--
Gustavo
Kalle Valo May 4, 2020, 11:54 a.m. UTC | #3
"Gustavo A. R. Silva" <gustavo@embeddedor.com> writes:

> Hi Arnd,
>
> On 4/30/20 16:30, Arnd Bergmann wrote:
>> gcc-10 started warning about out-of-bounds access for zero-length
>> arrays:
>> 
>> In file included from drivers/net/wireless/ath/ath10k/core.h:18,
>>                  from drivers/net/wireless/ath/ath10k/htt_rx.c:8:
>> drivers/net/wireless/ath/ath10k/htt_rx.c: In function 'ath10k_htt_rx_tx_fetch_ind':
>> drivers/net/wireless/ath/ath10k/htt.h:1683:17: warning: array subscript 65535 is outside the bounds of an interior zero-length array 'struct htt_tx_fetch_record[0]' [-Wzero-length-bounds]
>>  1683 |  return (void *)&ind->records[le16_to_cpu(ind->num_records)];
>>       |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> drivers/net/wireless/ath/ath10k/htt.h:1676:29: note: while referencing 'records'
>>  1676 |  struct htt_tx_fetch_record records[0];
>>       |                             ^~~~~~~
>> 
>> The structure was already converted to have a flexible-array member in
>> the past, but there are two zero-length members in the end and only
>> one of them can be a flexible-array member.
>> 
>> Swap the two around to avoid the warning, as 'resp_ids' is not accessed
>> in a way that causes a warning.
>> 
>> Fixes: 3ba225b506a2 ("treewide: Replace zero-length array with flexible-array member")
>> Fixes: 22e6b3bc5d96 ("ath10k: add new htt definitions")
>> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
>> ---
>>  drivers/net/wireless/ath/ath10k/htt.h | 4 ++--
>>  1 file changed, 2 insertions(+), 2 deletions(-)
>> 
>> diff --git a/drivers/net/wireless/ath/ath10k/htt.h b/drivers/net/wireless/ath/ath10k/htt.h
>> index e7096a73c6ca..7621f0a3dc77 100644
>> --- a/drivers/net/wireless/ath/ath10k/htt.h
>> +++ b/drivers/net/wireless/ath/ath10k/htt.h
>> @@ -1673,8 +1673,8 @@ struct htt_tx_fetch_ind {
>>  	__le32 token;
>>  	__le16 num_resp_ids;
>>  	__le16 num_records;
>> -	struct htt_tx_fetch_record records[0];
>> -	__le32 resp_ids[]; /* ath10k_htt_get_tx_fetch_ind_resp_ids() */
>> +	__le32 resp_ids[0]; /* ath10k_htt_get_tx_fetch_ind_resp_ids() */
>> +	struct htt_tx_fetch_record records[];
>>  } __packed;
>>  
>>  static inline void *
>> 
>
> The treewide patch is an experimental change and, as this change only applies
> to my -next tree, I will carry this patch in it, so other people don't have
> to worry about this at all.

Gustavo, why do you have ath10k patches in your tree? I prefer that
ath10k patches go through my ath.git tree so that they are reviewed and
tested.
Gustavo A. R. Silva May 4, 2020, 4:09 p.m. UTC | #4
On 5/4/20 06:54, Kalle Valo wrote:
> "Gustavo A. R. Silva" <gustavo@embeddedor.com> writes:
> 
>> Hi Arnd,
>>
>> On 4/30/20 16:30, Arnd Bergmann wrote:
>>> gcc-10 started warning about out-of-bounds access for zero-length
>>> arrays:
>>>
>>> In file included from drivers/net/wireless/ath/ath10k/core.h:18,
>>>                  from drivers/net/wireless/ath/ath10k/htt_rx.c:8:
>>> drivers/net/wireless/ath/ath10k/htt_rx.c: In function 'ath10k_htt_rx_tx_fetch_ind':
>>> drivers/net/wireless/ath/ath10k/htt.h:1683:17: warning: array subscript 65535 is outside the bounds of an interior zero-length array 'struct htt_tx_fetch_record[0]' [-Wzero-length-bounds]
>>>  1683 |  return (void *)&ind->records[le16_to_cpu(ind->num_records)];
>>>       |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>> drivers/net/wireless/ath/ath10k/htt.h:1676:29: note: while referencing 'records'
>>>  1676 |  struct htt_tx_fetch_record records[0];
>>>       |                             ^~~~~~~
>>>
>>> The structure was already converted to have a flexible-array member in
>>> the past, but there are two zero-length members in the end and only
>>> one of them can be a flexible-array member.
>>>
>>> Swap the two around to avoid the warning, as 'resp_ids' is not accessed
>>> in a way that causes a warning.
>>>
>>> Fixes: 3ba225b506a2 ("treewide: Replace zero-length array with flexible-array member")
>>> Fixes: 22e6b3bc5d96 ("ath10k: add new htt definitions")
>>> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
>>> ---
>>>  drivers/net/wireless/ath/ath10k/htt.h | 4 ++--
>>>  1 file changed, 2 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/net/wireless/ath/ath10k/htt.h b/drivers/net/wireless/ath/ath10k/htt.h
>>> index e7096a73c6ca..7621f0a3dc77 100644
>>> --- a/drivers/net/wireless/ath/ath10k/htt.h
>>> +++ b/drivers/net/wireless/ath/ath10k/htt.h
>>> @@ -1673,8 +1673,8 @@ struct htt_tx_fetch_ind {
>>>  	__le32 token;
>>>  	__le16 num_resp_ids;
>>>  	__le16 num_records;
>>> -	struct htt_tx_fetch_record records[0];
>>> -	__le32 resp_ids[]; /* ath10k_htt_get_tx_fetch_ind_resp_ids() */
>>> +	__le32 resp_ids[0]; /* ath10k_htt_get_tx_fetch_ind_resp_ids() */
>>> +	struct htt_tx_fetch_record records[];
>>>  } __packed;
>>>  
>>>  static inline void *
>>>
>>
>> The treewide patch is an experimental change and, as this change only applies
>> to my -next tree, I will carry this patch in it, so other people don't have
>> to worry about this at all.
> 
> Gustavo, why do you have ath10k patches in your tree? I prefer that
> ath10k patches go through my ath.git tree so that they are reviewed and
> tested.
> 

I just wanted to test out a mechanical change. I will remove it from my tree
now and will send a patch to you so you can apply it to your ath.git tree.

Thanks!
--
Gustavo
Kalle Valo May 5, 2020, 4:56 a.m. UTC | #5
"Gustavo A. R. Silva" <gustavo@embeddedor.com> writes:

> On 5/4/20 06:54, Kalle Valo wrote:
>> "Gustavo A. R. Silva" <gustavo@embeddedor.com> writes:
>> 
>>> Hi Arnd,
>>>
>>> On 4/30/20 16:30, Arnd Bergmann wrote:
>>>> gcc-10 started warning about out-of-bounds access for zero-length
>>>> arrays:
>>>>
>>>> In file included from drivers/net/wireless/ath/ath10k/core.h:18,
>>>>                  from drivers/net/wireless/ath/ath10k/htt_rx.c:8:
>>>> drivers/net/wireless/ath/ath10k/htt_rx.c: In function 'ath10k_htt_rx_tx_fetch_ind':
>>>> drivers/net/wireless/ath/ath10k/htt.h:1683:17: warning: array subscript 65535 is outside the bounds of an interior zero-length array 'struct htt_tx_fetch_record[0]' [-Wzero-length-bounds]
>>>>  1683 |  return (void *)&ind->records[le16_to_cpu(ind->num_records)];
>>>>       |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>>> drivers/net/wireless/ath/ath10k/htt.h:1676:29: note: while referencing 'records'
>>>>  1676 |  struct htt_tx_fetch_record records[0];
>>>>       |                             ^~~~~~~
>>>>
>>>> The structure was already converted to have a flexible-array member in
>>>> the past, but there are two zero-length members in the end and only
>>>> one of them can be a flexible-array member.
>>>>
>>>> Swap the two around to avoid the warning, as 'resp_ids' is not accessed
>>>> in a way that causes a warning.
>>>>
>>>> Fixes: 3ba225b506a2 ("treewide: Replace zero-length array with flexible-array member")
>>>> Fixes: 22e6b3bc5d96 ("ath10k: add new htt definitions")
>>>> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
>>>> ---
>>>>  drivers/net/wireless/ath/ath10k/htt.h | 4 ++--
>>>>  1 file changed, 2 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/drivers/net/wireless/ath/ath10k/htt.h b/drivers/net/wireless/ath/ath10k/htt.h
>>>> index e7096a73c6ca..7621f0a3dc77 100644
>>>> --- a/drivers/net/wireless/ath/ath10k/htt.h
>>>> +++ b/drivers/net/wireless/ath/ath10k/htt.h
>>>> @@ -1673,8 +1673,8 @@ struct htt_tx_fetch_ind {
>>>>  	__le32 token;
>>>>  	__le16 num_resp_ids;
>>>>  	__le16 num_records;
>>>> -	struct htt_tx_fetch_record records[0];
>>>> -	__le32 resp_ids[]; /* ath10k_htt_get_tx_fetch_ind_resp_ids() */
>>>> +	__le32 resp_ids[0]; /* ath10k_htt_get_tx_fetch_ind_resp_ids() */
>>>> +	struct htt_tx_fetch_record records[];
>>>>  } __packed;
>>>>  
>>>>  static inline void *
>>>>
>>>
>>> The treewide patch is an experimental change and, as this change only applies
>>> to my -next tree, I will carry this patch in it, so other people don't have
>>> to worry about this at all.
>> 
>> Gustavo, why do you have ath10k patches in your tree? I prefer that
>> ath10k patches go through my ath.git tree so that they are reviewed and
>> tested.
>> 
>
> I just wanted to test out a mechanical change. I will remove it from my tree
> now and will send a patch to you so you can apply it to your ath.git tree.

Great, thanks.
diff mbox series

Patch

diff --git a/drivers/net/wireless/ath/ath10k/htt.h b/drivers/net/wireless/ath/ath10k/htt.h
index e7096a73c6ca..7621f0a3dc77 100644
--- a/drivers/net/wireless/ath/ath10k/htt.h
+++ b/drivers/net/wireless/ath/ath10k/htt.h
@@ -1673,8 +1673,8 @@  struct htt_tx_fetch_ind {
 	__le32 token;
 	__le16 num_resp_ids;
 	__le16 num_records;
-	struct htt_tx_fetch_record records[0];
-	__le32 resp_ids[]; /* ath10k_htt_get_tx_fetch_ind_resp_ids() */
+	__le32 resp_ids[0]; /* ath10k_htt_get_tx_fetch_ind_resp_ids() */
+	struct htt_tx_fetch_record records[];
 } __packed;
 
 static inline void *