| Message ID | 20210711145101.1434065-1-keescook@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | media: atomisp: Perform a single memset() for union | expand |
On Sun, Jul 11, 2021 at 07:51:01AM -0700, Kees Cook wrote: > There is no need to memset() both dvs_grid_info and dvs_stat_grid_info > separately: they are part of the same union. Instead, just zero the > union itself. This additionally avoids a false positive (due to a > gcc optimization bug[1]) when building with the coming FORTIFY_SOURCE > improvements: > > In function 'fortify_memset_chk', > inlined from 'sh_css_pipe_get_grid_info' at drivers/staging/media/atomisp/pci/sh_css.c:5186:3, > inlined from 'ia_css_stream_create' at drivers/staging/media/atomisp/pci/sh_css.c:9442:10: > ./include/linux/fortify-string.h:199:4: warning: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Wattribute-warning] > 199 | __write_overflow_field(); > | ^~~~~~~~~~~~~~~~~~~~~~~~ > > [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101419 > > Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
diff --git a/drivers/staging/media/atomisp/pci/sh_css.c b/drivers/staging/media/atomisp/pci/sh_css.c index d26b1301eeb7..ffa7f8a88a70 100644 --- a/drivers/staging/media/atomisp/pci/sh_css.c +++ b/drivers/staging/media/atomisp/pci/sh_css.c @@ -5181,10 +5181,7 @@ sh_css_pipe_get_grid_info(struct ia_css_pipe *pipe, ia_css_binary_dvs_grid_info(binary, info, pipe); ia_css_binary_dvs_stat_grid_info(binary, info, pipe); } else { - memset(&info->dvs_grid.dvs_grid_info, 0, - sizeof(info->dvs_grid.dvs_grid_info)); - memset(&info->dvs_grid.dvs_stat_grid_info, 0, - sizeof(info->dvs_grid.dvs_stat_grid_info)); + memset(&info->dvs_grid, 0, sizeof(info->dvs_grid)); } if (binary) {
There is no need to memset() both dvs_grid_info and dvs_stat_grid_info separately: they are part of the same union. Instead, just zero the union itself. This additionally avoids a false positive (due to a gcc optimization bug[1]) when building with the coming FORTIFY_SOURCE improvements: In function 'fortify_memset_chk', inlined from 'sh_css_pipe_get_grid_info' at drivers/staging/media/atomisp/pci/sh_css.c:5186:3, inlined from 'ia_css_stream_create' at drivers/staging/media/atomisp/pci/sh_css.c:9442:10: ./include/linux/fortify-string.h:199:4: warning: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Wattribute-warning] 199 | __write_overflow_field(); | ^~~~~~~~~~~~~~~~~~~~~~~~ [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101419 Signed-off-by: Kees Cook <keescook@chromium.org> --- drivers/staging/media/atomisp/pci/sh_css.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-)