Re: warning: ‘memset’ offset [197, 448] from the object at ‘boot_params’ is out of the bounds of referenced subobject ‘ext_ramdisk_image’ with type, ‘unsigned int’ at offset 192 [-Warray-bounds]

[Greg KH <gregkh@linuxfoundation.org>]

On Thu, Aug 15, 2019 at 02:54:32PM +0200, Thomas Gleixner wrote:
> On Thu, 15 Aug 2019, Greg KH wrote:
> > On Tue, Aug 13, 2019 at 06:15:51PM +0200, Paul Menzel wrote:
> > > Dear Linux folks,
> > > 
> > > 
> > > No idea, if you are interested in these reports. Building Linux 5.3-rc4,
> > > GCC 9.2.0 shows the warning below.
> > > 
> > > ```
> > > In file included from arch/x86/kernel/head64.c:35:
> > > In function ‘sanitize_boot_params’,
> > >     inlined from ‘copy_bootdata’ at arch/x86/kernel/head64.c:391:2:
> > > ./arch/x86/include/asm/bootparam_utils.h:40:3: warning: ‘memset’ offset [197, 448] from the object at ‘boot_params’ is out of the bounds of referenced subobject ‘ext_ramdisk_image’ with type
> > >  ‘unsigned int’ at offset 192 [-Warray-bounds]
> > >    40 |   memset(&boot_params->ext_ramdisk_image, 0,
> > >       |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > >    41 |          (char *)&boot_params->efi_info -
> > >       |          ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > >    42 |    (char *)&boot_params->ext_ramdisk_image);
> > >       |    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > > ./arch/x86/include/asm/bootparam_utils.h:43:3: warning: ‘memset’ offset [493, 497] from the object at ‘boot_params’ is out of the bounds of referenced subobject ‘kbd_status’ with type ‘unsig
> > > ned char’ at offset 491 [-Warray-bounds]
> > >    43 |   memset(&boot_params->kbd_status, 0,
> > >       |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > >    44 |          (char *)&boot_params->hdr -
> > >       |          ~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > >    45 |          (char *)&boot_params->kbd_status);
> > >       |          ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > > ```
> > 
> > Yeah, it shows up on my builds as well :(
> > 
> > Any chance you can make a fix for this?
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?h=x86/boot&id=a156cadef2fe445ac423670eace517b39a01ccd0
> 
> I guess I need to reprioritize that and mark it for stable....


Please do, it's the only build warning I currently have for
'allmodconfig' on x86 for 4.14.y, 4.19.y, and 5.2.y and is annoying :)

thanks,

greg k-h