[next] drm/radeon: Replace 1-element arrays with flexible-array members

Message ID Y5LwqRCPcYLizJFt@mail.google.com
State New
Headers
Series [next] drm/radeon: Replace 1-element arrays with flexible-array members |

Commit Message

Paulo Miguel Almeida Dec. 9, 2022, 8:24 a.m. UTC
  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 structs _ATOM_DISPLAY_OBJECT_PATH,
_ATOM_DISPLAY_OBJECT_PATH_TABLE, _ATOM_OBJECT_TABLE, GOP_VBIOS_CONTENT
_ATOM_GPIO_VOLTAGE_OBJECT_V3 and refactor the rest of the code accordingly.

It's worth mentioning that doing a build before/after this patch
results in no binary output differences.

This helps with the ongoing efforts to tighten the FORTIFY_SOURCE
routines on memcpy() and help us make progress towards globally
enabling -fstrict-flex-arrays=3 [1].

Link: https://github.com/KSPP/linux/issues/79
Link: https://github.com/KSPP/linux/issues/239
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101836 [1]

Signed-off-by: Paulo Miguel Almeida <paulo.miguel.almeida.rodenas@gmail.com>
---
Notes for the maintainer:

- These are all fake-flexible arrays with references in source code for
  the radeon driver. Given the way they are used, no change to *.c files
  were required.
---
 drivers/gpu/drm/radeon/atombios.h | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)
  

Comments

Alex Deucher Dec. 9, 2022, 11:16 p.m. UTC | #1
Applied.  Thanks!

Alex

On Fri, Dec 9, 2022 at 3:24 AM Paulo Miguel Almeida
<paulo.miguel.almeida.rodenas@gmail.com> 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 structs _ATOM_DISPLAY_OBJECT_PATH,
> _ATOM_DISPLAY_OBJECT_PATH_TABLE, _ATOM_OBJECT_TABLE, GOP_VBIOS_CONTENT
> _ATOM_GPIO_VOLTAGE_OBJECT_V3 and refactor the rest of the code accordingly.
>
> It's worth mentioning that doing a build before/after this patch
> results in no binary output differences.
>
> This helps with the ongoing efforts to tighten the FORTIFY_SOURCE
> routines on memcpy() and help us make progress towards globally
> enabling -fstrict-flex-arrays=3 [1].
>
> Link: https://github.com/KSPP/linux/issues/79
> Link: https://github.com/KSPP/linux/issues/239
> Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101836 [1]
>
> Signed-off-by: Paulo Miguel Almeida <paulo.miguel.almeida.rodenas@gmail.com>
> ---
> Notes for the maintainer:
>
> - These are all fake-flexible arrays with references in source code for
>   the radeon driver. Given the way they are used, no change to *.c files
>   were required.
> ---
>  drivers/gpu/drm/radeon/atombios.h | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/radeon/atombios.h b/drivers/gpu/drm/radeon/atombios.h
> index 235e59b547a1..8a6621f1e82c 100644
> --- a/drivers/gpu/drm/radeon/atombios.h
> +++ b/drivers/gpu/drm/radeon/atombios.h
> @@ -4020,7 +4020,7 @@ typedef struct  _ATOM_DISPLAY_OBJECT_PATH
>    USHORT    usSize;                                        //the size of ATOM_DISPLAY_OBJECT_PATH
>    USHORT    usConnObjectId;                                //Connector Object ID
>    USHORT    usGPUObjectId;                                 //GPU ID
> -  USHORT    usGraphicObjIds[1];                             //1st Encoder Obj source from GPU to last Graphic Obj destinate to connector.
> +  USHORT    usGraphicObjIds[];                             //1st Encoder Obj source from GPU to last Graphic Obj destinate to connector.
>  }ATOM_DISPLAY_OBJECT_PATH;
>
>  typedef struct  _ATOM_DISPLAY_EXTERNAL_OBJECT_PATH
> @@ -4037,7 +4037,7 @@ typedef struct _ATOM_DISPLAY_OBJECT_PATH_TABLE
>    UCHAR                           ucNumOfDispPath;
>    UCHAR                           ucVersion;
>    UCHAR                           ucPadding[2];
> -  ATOM_DISPLAY_OBJECT_PATH        asDispPath[1];
> +  ATOM_DISPLAY_OBJECT_PATH        asDispPath[];
>  }ATOM_DISPLAY_OBJECT_PATH_TABLE;
>
>
> @@ -4053,7 +4053,7 @@ typedef struct _ATOM_OBJECT_TABLE                         //Above 4 object table
>  {
>    UCHAR               ucNumberOfObjects;
>    UCHAR               ucPadding[3];
> -  ATOM_OBJECT         asObjects[1];
> +  ATOM_OBJECT         asObjects[];
>  }ATOM_OBJECT_TABLE;
>
>  typedef struct _ATOM_SRC_DST_TABLE_FOR_ONE_OBJECT         //usSrcDstTableOffset pointing to this structure
> @@ -4615,7 +4615,7 @@ typedef struct  _ATOM_GPIO_VOLTAGE_OBJECT_V3
>     UCHAR    ucPhaseDelay;                // phase delay in unit of micro second
>     UCHAR    ucReserved;
>     ULONG    ulGpioMaskVal;               // GPIO Mask value
> -   VOLTAGE_LUT_ENTRY_V2 asVolGpioLut[1];
> +   VOLTAGE_LUT_ENTRY_V2 asVolGpioLut[];
>  }ATOM_GPIO_VOLTAGE_OBJECT_V3;
>
>  typedef struct  _ATOM_LEAKAGE_VOLTAGE_OBJECT_V3
> @@ -7964,7 +7964,7 @@ typedef struct {
>
>  typedef struct {
>    VFCT_IMAGE_HEADER    VbiosHeader;
> -  UCHAR        VbiosContent[1];
> +  UCHAR        VbiosContent[];
>  }GOP_VBIOS_CONTENT;
>
>  typedef struct {
> --
> 2.38.1
>
  

Patch

diff --git a/drivers/gpu/drm/radeon/atombios.h b/drivers/gpu/drm/radeon/atombios.h
index 235e59b547a1..8a6621f1e82c 100644
--- a/drivers/gpu/drm/radeon/atombios.h
+++ b/drivers/gpu/drm/radeon/atombios.h
@@ -4020,7 +4020,7 @@  typedef struct  _ATOM_DISPLAY_OBJECT_PATH
   USHORT    usSize;                                        //the size of ATOM_DISPLAY_OBJECT_PATH
   USHORT    usConnObjectId;                                //Connector Object ID 
   USHORT    usGPUObjectId;                                 //GPU ID 
-  USHORT    usGraphicObjIds[1];                             //1st Encoder Obj source from GPU to last Graphic Obj destinate to connector.
+  USHORT    usGraphicObjIds[];                             //1st Encoder Obj source from GPU to last Graphic Obj destinate to connector.
 }ATOM_DISPLAY_OBJECT_PATH;
 
 typedef struct  _ATOM_DISPLAY_EXTERNAL_OBJECT_PATH
@@ -4037,7 +4037,7 @@  typedef struct _ATOM_DISPLAY_OBJECT_PATH_TABLE
   UCHAR                           ucNumOfDispPath;
   UCHAR                           ucVersion;
   UCHAR                           ucPadding[2];
-  ATOM_DISPLAY_OBJECT_PATH        asDispPath[1];
+  ATOM_DISPLAY_OBJECT_PATH        asDispPath[];
 }ATOM_DISPLAY_OBJECT_PATH_TABLE;
 
 
@@ -4053,7 +4053,7 @@  typedef struct _ATOM_OBJECT_TABLE                         //Above 4 object table
 {
   UCHAR               ucNumberOfObjects;
   UCHAR               ucPadding[3];
-  ATOM_OBJECT         asObjects[1];
+  ATOM_OBJECT         asObjects[];
 }ATOM_OBJECT_TABLE;
 
 typedef struct _ATOM_SRC_DST_TABLE_FOR_ONE_OBJECT         //usSrcDstTableOffset pointing to this structure
@@ -4615,7 +4615,7 @@  typedef struct  _ATOM_GPIO_VOLTAGE_OBJECT_V3
    UCHAR    ucPhaseDelay;                // phase delay in unit of micro second
    UCHAR    ucReserved;   
    ULONG    ulGpioMaskVal;               // GPIO Mask value
-   VOLTAGE_LUT_ENTRY_V2 asVolGpioLut[1];   
+   VOLTAGE_LUT_ENTRY_V2 asVolGpioLut[];
 }ATOM_GPIO_VOLTAGE_OBJECT_V3;
 
 typedef struct  _ATOM_LEAKAGE_VOLTAGE_OBJECT_V3
@@ -7964,7 +7964,7 @@  typedef struct {
 
 typedef struct {
   VFCT_IMAGE_HEADER	VbiosHeader;
-  UCHAR	VbiosContent[1];
+  UCHAR	VbiosContent[];
 }GOP_VBIOS_CONTENT;
 
 typedef struct {