diff mbox series

kni: fix build with gcc 8.1

Message ID 20180619120855.78207-1-ferruh.yigit@intel.com (mailing list archive)
State Superseded, archived
Delegated to: Thomas Monjalon
Headers
Series kni: fix build with gcc 8.1 |

Checks

Context Check Description
ci/checkpatch success coding style OK
ci/Intel-compilation success Compilation OK

Commit Message

Ferruh Yigit June 19, 2018, 12:08 p.m. UTC 
  Error observed when CONFIG_RTE_KNI_KMOD_ETHTOOL config option is
enabled.

build error:
In function ‘strncpy’,
    inlined from ‘igb_get_drvinfo’ at
    .../dpdk/build/build/kernel/linux/kni/igb_ethtool.c:814:2:
    .../include/linux/string.h:246:9: error: ‘__builtin_strncpy’ output
    may be truncated copying 31 bytes from a string of length 42
    [-Werror=stringop-truncation]
      return __builtin_strncpy(p, q, size);
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Fixed by reducing the adapter->fw_version size and adjusting strncpy
limit size.

Cc: stable@dpdk.org

Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
---
 kernel/linux/kni/ethtool/igb/igb.h         | 2 +-
 kernel/linux/kni/ethtool/igb/igb_ethtool.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

Comments

Stephen Hemminger June 19, 2018, 11:35 p.m. UTC | #1 
On Tue, 19 Jun 2018 13:08:55 +0100
Ferruh Yigit <ferruh.yigit@intel.com> wrote:

> Error observed when CONFIG_RTE_KNI_KMOD_ETHTOOL config option is
> enabled.
> 
> build error:
> In function ‘strncpy’,
>     inlined from ‘igb_get_drvinfo’ at
>     .../dpdk/build/build/kernel/linux/kni/igb_ethtool.c:814:2:
>     .../include/linux/string.h:246:9: error: ‘__builtin_strncpy’ output
>     may be truncated copying 31 bytes from a string of length 42
>     [-Werror=stringop-truncation]
>       return __builtin_strncpy(p, q, size);
>                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> Fixed by reducing the adapter->fw_version size and adjusting strncpy
> limit size.
> 
> Cc: stable@dpdk.org
> 
> Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
> ---
>  kernel/linux/kni/ethtool/igb/igb.h         | 2 +-
>  kernel/linux/kni/ethtool/igb/igb_ethtool.c | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/kernel/linux/kni/ethtool/igb/igb.h b/kernel/linux/kni/ethtool/igb/igb.h
> index 8aa2a3088..5e798ae83 100644
> --- a/kernel/linux/kni/ethtool/igb/igb.h
> +++ b/kernel/linux/kni/ethtool/igb/igb.h
> @@ -592,7 +592,7 @@ struct igb_adapter {
>  	int int_mode;
>  	u32 rss_queues;
>  	u32 vmdq_pools;
> -	char fw_version[43];
> +	char fw_version[32];

Use ETHTOOL_FWVERS_LEN?

>  	u32 wvbr;
>  	struct igb_mac_addr *mac_table;
>  #ifdef CONFIG_IGB_VMDQ_NETDEV
> diff --git a/kernel/linux/kni/ethtool/igb/igb_ethtool.c b/kernel/linux/kni/ethtool/igb/igb_ethtool.c
> index 064528bcf..0b8b25ff1 100644
> --- a/kernel/linux/kni/ethtool/igb/igb_ethtool.c
> +++ b/kernel/linux/kni/ethtool/igb/igb_ethtool.c
> @@ -812,7 +812,7 @@ static void igb_get_drvinfo(struct net_device *netdev,
>  	strncpy(drvinfo->version, igb_driver_version, sizeof(drvinfo->version) - 1);
>  
>  	strncpy(drvinfo->fw_version, adapter->fw_version,
> -		sizeof(drvinfo->fw_version) - 1);
> +		sizeof(drvinfo->fw_version));

Why not:
	strlcpy(drvinfo->fw_version, adapter->fw_version,
		sizeof(drvinfo->fw_version));
De Lara Guarch, Pablo June 20, 2018, 9:01 a.m. UTC | #2 
> -----Original Message-----
> From: stable [mailto:stable-bounces@dpdk.org] On Behalf Of Ferruh Yigit
> Sent: Tuesday, June 19, 2018 1:09 PM
> To: Yigit, Ferruh <ferruh.yigit@intel.com>
> Cc: dev@dpdk.org; stable@dpdk.org
> Subject: [dpdk-stable] [PATCH] kni: fix build with gcc 8.1
> 
> Error observed when CONFIG_RTE_KNI_KMOD_ETHTOOL config option is
> enabled.
> 
> build error:
> In function ‘strncpy’,
>     inlined from ‘igb_get_drvinfo’ at
>     .../dpdk/build/build/kernel/linux/kni/igb_ethtool.c:814:2:
>     .../include/linux/string.h:246:9: error: ‘__builtin_strncpy’ output
>     may be truncated copying 31 bytes from a string of length 42
>     [-Werror=stringop-truncation]
>       return __builtin_strncpy(p, q, size);
>                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> Fixed by reducing the adapter->fw_version size and adjusting strncpy limit size.
> 
> Cc: stable@dpdk.org
>

Fixes line?
 
> Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>

...

> --- a/kernel/linux/kni/ethtool/igb/igb_ethtool.c
> +++ b/kernel/linux/kni/ethtool/igb/igb_ethtool.c
> @@ -812,7 +812,7 @@ static void igb_get_drvinfo(struct net_device *netdev,
>  	strncpy(drvinfo->version, igb_driver_version, sizeof(drvinfo->version) -
> 1);
> 
>  	strncpy(drvinfo->fw_version, adapter->fw_version,
> -		sizeof(drvinfo->fw_version) - 1);
> +		sizeof(drvinfo->fw_version));
>  	strncpy(drvinfo->bus_info, pci_name(adapter->pdev), sizeof(drvinfo-
> >bus_info) -1);

This patch fixes the compilation issue, but should we use strlcpy instead of strncpy?

Thanks,
Pablo
Ferruh Yigit June 20, 2018, 4:39 p.m. UTC | #3 
On 6/20/2018 12:35 AM, Stephen Hemminger wrote:
> On Tue, 19 Jun 2018 13:08:55 +0100
> Ferruh Yigit <ferruh.yigit@intel.com> wrote:
> 
>> Error observed when CONFIG_RTE_KNI_KMOD_ETHTOOL config option is
>> enabled.
>>
>> build error:
>> In function ‘strncpy’,
>>     inlined from ‘igb_get_drvinfo’ at
>>     .../dpdk/build/build/kernel/linux/kni/igb_ethtool.c:814:2:
>>     .../include/linux/string.h:246:9: error: ‘__builtin_strncpy’ output
>>     may be truncated copying 31 bytes from a string of length 42
>>     [-Werror=stringop-truncation]
>>       return __builtin_strncpy(p, q, size);
>>                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>
>> Fixed by reducing the adapter->fw_version size and adjusting strncpy
>> limit size.
>>
>> Cc: stable@dpdk.org
>>
>> Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
>> ---
>>  kernel/linux/kni/ethtool/igb/igb.h         | 2 +-
>>  kernel/linux/kni/ethtool/igb/igb_ethtool.c | 2 +-
>>  2 files changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/kernel/linux/kni/ethtool/igb/igb.h b/kernel/linux/kni/ethtool/igb/igb.h
>> index 8aa2a3088..5e798ae83 100644
>> --- a/kernel/linux/kni/ethtool/igb/igb.h
>> +++ b/kernel/linux/kni/ethtool/igb/igb.h
>> @@ -592,7 +592,7 @@ struct igb_adapter {
>>  	int int_mode;
>>  	u32 rss_queues;
>>  	u32 vmdq_pools;
>> -	char fw_version[43];
>> +	char fw_version[32];
> 
> Use ETHTOOL_FWVERS_LEN?

Yes, that is what drvinfo->fw_version uses, and it seems it has been around
enough to not cause any build issue, will use that one.

> 
>>  	u32 wvbr;
>>  	struct igb_mac_addr *mac_table;
>>  #ifdef CONFIG_IGB_VMDQ_NETDEV
>> diff --git a/kernel/linux/kni/ethtool/igb/igb_ethtool.c b/kernel/linux/kni/ethtool/igb/igb_ethtool.c
>> index 064528bcf..0b8b25ff1 100644
>> --- a/kernel/linux/kni/ethtool/igb/igb_ethtool.c
>> +++ b/kernel/linux/kni/ethtool/igb/igb_ethtool.c
>> @@ -812,7 +812,7 @@ static void igb_get_drvinfo(struct net_device *netdev,
>>  	strncpy(drvinfo->version, igb_driver_version, sizeof(drvinfo->version) - 1);
>>  
>>  	strncpy(drvinfo->fw_version, adapter->fw_version,
>> -		sizeof(drvinfo->fw_version) - 1);
>> +		sizeof(drvinfo->fw_version));
> 
> Why not:
> 	strlcpy(drvinfo->fw_version, adapter->fw_version,
> 		sizeof(drvinfo->fw_version));

Just to be cautious about changing API, to not have any problem with older
version of kernels.
But it seems strlcpy supported long enough to not cause an issue, I will use it.
Ferruh Yigit June 20, 2018, 4:40 p.m. UTC | #4 
On 6/20/2018 10:01 AM, De Lara Guarch, Pablo wrote:
> 
> 
>> -----Original Message-----
>> From: stable [mailto:stable-bounces@dpdk.org] On Behalf Of Ferruh Yigit
>> Sent: Tuesday, June 19, 2018 1:09 PM
>> To: Yigit, Ferruh <ferruh.yigit@intel.com>
>> Cc: dev@dpdk.org; stable@dpdk.org
>> Subject: [dpdk-stable] [PATCH] kni: fix build with gcc 8.1
>>
>> Error observed when CONFIG_RTE_KNI_KMOD_ETHTOOL config option is
>> enabled.
>>
>> build error:
>> In function ‘strncpy’,
>>     inlined from ‘igb_get_drvinfo’ at
>>     .../dpdk/build/build/kernel/linux/kni/igb_ethtool.c:814:2:
>>     .../include/linux/string.h:246:9: error: ‘__builtin_strncpy’ output
>>     may be truncated copying 31 bytes from a string of length 42
>>     [-Werror=stringop-truncation]
>>       return __builtin_strncpy(p, q, size);
>>                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>
>> Fixed by reducing the adapter->fw_version size and adjusting strncpy limit size.
>>
>> Cc: stable@dpdk.org
>>
> 
> Fixes line?

I will add.

>  
>> Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
> 
> ...
> 
>> --- a/kernel/linux/kni/ethtool/igb/igb_ethtool.c
>> +++ b/kernel/linux/kni/ethtool/igb/igb_ethtool.c
>> @@ -812,7 +812,7 @@ static void igb_get_drvinfo(struct net_device *netdev,
>>  	strncpy(drvinfo->version, igb_driver_version, sizeof(drvinfo->version) -
>> 1);
>>
>>  	strncpy(drvinfo->fw_version, adapter->fw_version,
>> -		sizeof(drvinfo->fw_version) - 1);
>> +		sizeof(drvinfo->fw_version));
>>  	strncpy(drvinfo->bus_info, pci_name(adapter->pdev), sizeof(drvinfo-
>>> bus_info) -1);
> 
> This patch fixes the compilation issue, but should we use strlcpy instead of strncpy?
> 
> Thanks,
> Pablo
>
Ferruh Yigit June 20, 2018, 5:04 p.m. UTC | #5 
On 6/20/2018 5:39 PM, Ferruh Yigit wrote:
> On 6/20/2018 12:35 AM, Stephen Hemminger wrote:
>> On Tue, 19 Jun 2018 13:08:55 +0100
>> Ferruh Yigit <ferruh.yigit@intel.com> wrote:
>>
>>> Error observed when CONFIG_RTE_KNI_KMOD_ETHTOOL config option is
>>> enabled.
>>>
>>> build error:
>>> In function ‘strncpy’,
>>>     inlined from ‘igb_get_drvinfo’ at
>>>     .../dpdk/build/build/kernel/linux/kni/igb_ethtool.c:814:2:
>>>     .../include/linux/string.h:246:9: error: ‘__builtin_strncpy’ output
>>>     may be truncated copying 31 bytes from a string of length 42
>>>     [-Werror=stringop-truncation]
>>>       return __builtin_strncpy(p, q, size);
>>>                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>>
>>> Fixed by reducing the adapter->fw_version size and adjusting strncpy
>>> limit size.
>>>
>>> Cc: stable@dpdk.org
>>>
>>> Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
>>> ---
>>>  kernel/linux/kni/ethtool/igb/igb.h         | 2 +-
>>>  kernel/linux/kni/ethtool/igb/igb_ethtool.c | 2 +-
>>>  2 files changed, 2 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/kernel/linux/kni/ethtool/igb/igb.h b/kernel/linux/kni/ethtool/igb/igb.h
>>> index 8aa2a3088..5e798ae83 100644
>>> --- a/kernel/linux/kni/ethtool/igb/igb.h
>>> +++ b/kernel/linux/kni/ethtool/igb/igb.h
>>> @@ -592,7 +592,7 @@ struct igb_adapter {
>>>  	int int_mode;
>>>  	u32 rss_queues;
>>>  	u32 vmdq_pools;
>>> -	char fw_version[43];
>>> +	char fw_version[32];
>>
>> Use ETHTOOL_FWVERS_LEN?
> 
> Yes, that is what drvinfo->fw_version uses, and it seems it has been around
> enough to not cause any build issue, will use that one.

Ah so much fun, it has been updated to 43 by me in the past, to prevent another
warning [1] which another part of code has potential to write larger string to
fw_version.

Reducing value back to 32 may bring back that old warning ...

[1]
Fixes: c3698192940c ("kni: fix build with gcc 7.1")

> 
>>
>>>  	u32 wvbr;
>>>  	struct igb_mac_addr *mac_table;
>>>  #ifdef CONFIG_IGB_VMDQ_NETDEV
>>> diff --git a/kernel/linux/kni/ethtool/igb/igb_ethtool.c b/kernel/linux/kni/ethtool/igb/igb_ethtool.c
>>> index 064528bcf..0b8b25ff1 100644
>>> --- a/kernel/linux/kni/ethtool/igb/igb_ethtool.c
>>> +++ b/kernel/linux/kni/ethtool/igb/igb_ethtool.c
>>> @@ -812,7 +812,7 @@ static void igb_get_drvinfo(struct net_device *netdev,
>>>  	strncpy(drvinfo->version, igb_driver_version, sizeof(drvinfo->version) - 1);
>>>  
>>>  	strncpy(drvinfo->fw_version, adapter->fw_version,
>>> -		sizeof(drvinfo->fw_version) - 1);
>>> +		sizeof(drvinfo->fw_version));
>>
>> Why not:
>> 	strlcpy(drvinfo->fw_version, adapter->fw_version,
>> 		sizeof(drvinfo->fw_version));
> 
> Just to be cautious about changing API, to not have any problem with older
> version of kernels.
> But it seems strlcpy supported long enough to not cause an issue, I will use it.
>
diff mbox series

Patch

diff --git a/kernel/linux/kni/ethtool/igb/igb.h b/kernel/linux/kni/ethtool/igb/igb.h
index 8aa2a3088..5e798ae83 100644
--- a/kernel/linux/kni/ethtool/igb/igb.h
+++ b/kernel/linux/kni/ethtool/igb/igb.h
@@ -592,7 +592,7 @@  struct igb_adapter {
 	int int_mode;
 	u32 rss_queues;
 	u32 vmdq_pools;
-	char fw_version[43];
+	char fw_version[32];
 	u32 wvbr;
 	struct igb_mac_addr *mac_table;
 #ifdef CONFIG_IGB_VMDQ_NETDEV
diff --git a/kernel/linux/kni/ethtool/igb/igb_ethtool.c b/kernel/linux/kni/ethtool/igb/igb_ethtool.c
index 064528bcf..0b8b25ff1 100644
--- a/kernel/linux/kni/ethtool/igb/igb_ethtool.c
+++ b/kernel/linux/kni/ethtool/igb/igb_ethtool.c
@@ -812,7 +812,7 @@  static void igb_get_drvinfo(struct net_device *netdev,
 	strncpy(drvinfo->version, igb_driver_version, sizeof(drvinfo->version) - 1);
 
 	strncpy(drvinfo->fw_version, adapter->fw_version,
-		sizeof(drvinfo->fw_version) - 1);
+		sizeof(drvinfo->fw_version));
 	strncpy(drvinfo->bus_info, pci_name(adapter->pdev), sizeof(drvinfo->bus_info) -1);
 	drvinfo->n_stats = IGB_STATS_LEN;
 	drvinfo->testinfo_len = IGB_TEST_LEN;