[PATCH v3][next] scsi: smartpqi: Replace one-element array with flexible-array member

[PATCH v3][next] scsi: smartpqi: Replace one-element array with flexible-array member

[Gustavo A. R. Silva]

One-element arrays are deprecated, and we are replacing them with flexible
array members instead. So, replace one-element array with flexible-array
member in struct report_log_lun_list.

This helps with the ongoing efforts to tighten the FORTIFY_SOURCE routines
on memcpy().

Link: https://github.com/KSPP/linux/issues/79
Link: https://github.com/KSPP/linux/issues/204
Acked-by: Don Brace <don.brace@microchip.com>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
---
Changes in v3:
 - Amplify the existing comment instead of adding a new one. By Don
   Brace[1].
 - Add Don's Acked-by tag to the changelog.
   Link: https://lore.kernel.org/linux-hardening/d881ad98-a291-1c9b-53dc-199f23f1625e@embeddedor.com/ [1]

Changes in v2:
 - In v1 we thought that the original code was allocating one too-many
   entries for the list. However, Don Brace commented that the allocation
   was actually intentional[2]. So, I added a code comment with his feedback.
   Link: https://lore.kernel.org/linux-hardening/16e6c434-44af-2efb-d4bc-a253e93e5590@embeddedor.com/  [2]

v1:
 - Link: https://lore.kernel.org/linux-hardening/c80c0979933e0c05e80d95792ef167a28640a14b.1663816572.git.gustavoars@kernel.org/

 drivers/scsi/smartpqi/smartpqi.h      | 2 +-
 drivers/scsi/smartpqi/smartpqi_init.c | 3 ++-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/smartpqi/smartpqi.h b/drivers/scsi/smartpqi/smartpqi.h
index af27bb0f3133..228838eb3686 100644
--- a/drivers/scsi/smartpqi/smartpqi.h
+++ b/drivers/scsi/smartpqi/smartpqi.h
@@ -954,7 +954,7 @@ struct report_log_lun {
 
 struct report_log_lun_list {
 	struct report_lun_header header;
-	struct report_log_lun lun_entries[1];
+	struct report_log_lun lun_entries[];
 };
 
 struct report_phys_lun_8byte_wwid {
diff --git a/drivers/scsi/smartpqi/smartpqi_init.c b/drivers/scsi/smartpqi/smartpqi_init.c
index d0446d4d4465..49a8f91810b6 100644
--- a/drivers/scsi/smartpqi/smartpqi_init.c
+++ b/drivers/scsi/smartpqi/smartpqi_init.c
@@ -1259,7 +1259,8 @@ static int pqi_get_device_lists(struct pqi_ctrl_info *ctrl_info,
 			"report logical LUNs failed\n");
 
 	/*
-	 * Tack the controller itself onto the end of the logical device list.
+	 * Tack the controller itself onto the end of the logical device list
+	 * by adding a list entry that is all zeros.
 	 */
 
 	logdev_data = *logdev_list;
-- 
2.34.1

Re: [PATCH v3][next] scsi: smartpqi: Replace one-element array with flexible-array member

[Kees Cook]

On Tue, Feb 07, 2023 at 03:59:43PM -0600, Gustavo A. R. Silva wrote:
> One-element arrays are deprecated, and we are replacing them with flexible
> array members instead. So, replace one-element array with flexible-array
> member in struct report_log_lun_list.
> 
> This helps with the ongoing efforts to tighten the FORTIFY_SOURCE routines
> on memcpy().
> 
> Link: https://github.com/KSPP/linux/issues/79
> Link: https://github.com/KSPP/linux/issues/204
> Acked-by: Don Brace <don.brace@microchip.com>
> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

Looks good to me -- both before and after, there is 1 extra all-zero
entry at the end. But now the struct is using a flex array correctly.

Reviewed-by: Kees Cook <keescook@chromium.org>

-Kees

> ---
> Changes in v3:
>  - Amplify the existing comment instead of adding a new one. By Don
>    Brace[1].
>  - Add Don's Acked-by tag to the changelog.
>    Link: https://lore.kernel.org/linux-hardening/d881ad98-a291-1c9b-53dc-199f23f1625e@embeddedor.com/ [1]
> 
> Changes in v2:
>  - In v1 we thought that the original code was allocating one too-many
>    entries for the list. However, Don Brace commented that the allocation
>    was actually intentional[2]. So, I added a code comment with his feedback.
>    Link: https://lore.kernel.org/linux-hardening/16e6c434-44af-2efb-d4bc-a253e93e5590@embeddedor.com/  [2]
> 
> v1:
>  - Link: https://lore.kernel.org/linux-hardening/c80c0979933e0c05e80d95792ef167a28640a14b.1663816572.git.gustavoars@kernel.org/
> 
>  drivers/scsi/smartpqi/smartpqi.h      | 2 +-
>  drivers/scsi/smartpqi/smartpqi_init.c | 3 ++-
>  2 files changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/scsi/smartpqi/smartpqi.h b/drivers/scsi/smartpqi/smartpqi.h
> index af27bb0f3133..228838eb3686 100644
> --- a/drivers/scsi/smartpqi/smartpqi.h
> +++ b/drivers/scsi/smartpqi/smartpqi.h
> @@ -954,7 +954,7 @@ struct report_log_lun {
>  
>  struct report_log_lun_list {
>  	struct report_lun_header header;
> -	struct report_log_lun lun_entries[1];
> +	struct report_log_lun lun_entries[];
>  };
>  
>  struct report_phys_lun_8byte_wwid {
> diff --git a/drivers/scsi/smartpqi/smartpqi_init.c b/drivers/scsi/smartpqi/smartpqi_init.c
> index d0446d4d4465..49a8f91810b6 100644
> --- a/drivers/scsi/smartpqi/smartpqi_init.c
> +++ b/drivers/scsi/smartpqi/smartpqi_init.c
> @@ -1259,7 +1259,8 @@ static int pqi_get_device_lists(struct pqi_ctrl_info *ctrl_info,
>  			"report logical LUNs failed\n");
>  
>  	/*
> -	 * Tack the controller itself onto the end of the logical device list.
> +	 * Tack the controller itself onto the end of the logical device list
> +	 * by adding a list entry that is all zeros.
>  	 */
>  
>  	logdev_data = *logdev_list;
> -- 
> 2.34.1
> 

-- 
Kees Cook

Re: [PATCH v3][next] scsi: smartpqi: Replace one-element array with flexible-array member

[Gustavo A. R. Silva]

On 2/7/23 17:01, Kees Cook wrote:
> On Tue, Feb 07, 2023 at 03:59:43PM -0600, Gustavo A. R. Silva wrote:
>> One-element arrays are deprecated, and we are replacing them with flexible
>> array members instead. So, replace one-element array with flexible-array
>> member in struct report_log_lun_list.
>>
>> This helps with the ongoing efforts to tighten the FORTIFY_SOURCE routines
>> on memcpy().
>>
>> Link: https://github.com/KSPP/linux/issues/79
>> Link: https://github.com/KSPP/linux/issues/204
>> Acked-by: Don Brace <don.brace@microchip.com>
>> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
> 
> Looks good to me -- both before and after, there is 1 extra all-zero
> entry at the end. But now the struct is using a flex array correctly.

Yep. :)

> 
> Reviewed-by: Kees Cook <keescook@chromium.org>

Thanks!
--
Gustavo

> 
> -Kees
> 
>> ---
>> Changes in v3:
>>   - Amplify the existing comment instead of adding a new one. By Don
>>     Brace[1].
>>   - Add Don's Acked-by tag to the changelog.
>>     Link: https://lore.kernel.org/linux-hardening/d881ad98-a291-1c9b-53dc-199f23f1625e@embeddedor.com/ [1]
>>
>> Changes in v2:
>>   - In v1 we thought that the original code was allocating one too-many
>>     entries for the list. However, Don Brace commented that the allocation
>>     was actually intentional[2]. So, I added a code comment with his feedback.
>>     Link: https://lore.kernel.org/linux-hardening/16e6c434-44af-2efb-d4bc-a253e93e5590@embeddedor.com/  [2]
>>
>> v1:
>>   - Link: https://lore.kernel.org/linux-hardening/c80c0979933e0c05e80d95792ef167a28640a14b.1663816572.git.gustavoars@kernel.org/
>>
>>   drivers/scsi/smartpqi/smartpqi.h      | 2 +-
>>   drivers/scsi/smartpqi/smartpqi_init.c | 3 ++-
>>   2 files changed, 3 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/scsi/smartpqi/smartpqi.h b/drivers/scsi/smartpqi/smartpqi.h
>> index af27bb0f3133..228838eb3686 100644
>> --- a/drivers/scsi/smartpqi/smartpqi.h
>> +++ b/drivers/scsi/smartpqi/smartpqi.h
>> @@ -954,7 +954,7 @@ struct report_log_lun {
>>   
>>   struct report_log_lun_list {
>>   	struct report_lun_header header;
>> -	struct report_log_lun lun_entries[1];
>> +	struct report_log_lun lun_entries[];
>>   };
>>   
>>   struct report_phys_lun_8byte_wwid {
>> diff --git a/drivers/scsi/smartpqi/smartpqi_init.c b/drivers/scsi/smartpqi/smartpqi_init.c
>> index d0446d4d4465..49a8f91810b6 100644
>> --- a/drivers/scsi/smartpqi/smartpqi_init.c
>> +++ b/drivers/scsi/smartpqi/smartpqi_init.c
>> @@ -1259,7 +1259,8 @@ static int pqi_get_device_lists(struct pqi_ctrl_info *ctrl_info,
>>   			"report logical LUNs failed\n");
>>   
>>   	/*
>> -	 * Tack the controller itself onto the end of the logical device list.
>> +	 * Tack the controller itself onto the end of the logical device list
>> +	 * by adding a list entry that is all zeros.
>>   	 */
>>   
>>   	logdev_data = *logdev_list;
>> -- 
>> 2.34.1
>>
> 

Re: [PATCH v3][next] scsi: smartpqi: Replace one-element array with flexible-array member

[Martin K. Petersen]

Gustavo,

> One-element arrays are deprecated, and we are replacing them with
> flexible array members instead. So, replace one-element array with
> flexible-array member in struct report_log_lun_list.

Applied to 6.3/scsi-staging, thanks!

-- 
Martin K. Petersen	Oracle Linux Engineering

Re: [PATCH v3][next] scsi: smartpqi: Replace one-element array with flexible-array member

[Martin K. Petersen]

On Tue, 07 Feb 2023 15:59:43 -0600, Gustavo A. R. Silva wrote:

> One-element arrays are deprecated, and we are replacing them with flexible
> array members instead. So, replace one-element array with flexible-array
> member in struct report_log_lun_list.
> 
> This helps with the ongoing efforts to tighten the FORTIFY_SOURCE routines
> on memcpy().
> 
> [...]

Applied to 6.3/scsi-queue, thanks!

[1/1] scsi: smartpqi: Replace one-element array with flexible-array member
      https://git.kernel.org/mkp/scsi/c/ead821268c14

-- 
Martin K. Petersen	Oracle Linux Engineering