Adding dri-devel too, not sure anyone is still listening on linux-fbdev.
On Sun, Oct 18, 2020 at 8:13 PM Peilin Ye <yepeilin.cs@xxxxxxxxx> wrote:
>
> Recently, in commit 6735b4632def ("Fonts: Support FONT_EXTRA_WORDS macros
> for built-in fonts"), we wrapped each of our built-in data buffers in a
> `font_data` structure, in order to use the following macros on them, see
> include/linux/font.h:
>
> #define REFCOUNT(fd) (((int *)(fd))[-1])
> #define FNTSIZE(fd) (((int *)(fd))[-2])
> #define FNTCHARCNT(fd) (((int *)(fd))[-3])
> #define FNTSUM(fd) (((int *)(fd))[-4])
>
> #define FONT_EXTRA_WORDS 4
>
> Do the same thing to our new 6x8 font. For built-in fonts, currently we
> only use FNTSIZE(). Since this is only a temporary solution for an
> out-of-bounds issue in the framebuffer layer (see commit 5af08640795b
> ("fbcon: Fix global-out-of-bounds read in fbcon_get_font()")), all the
> three other fields are intentionally set to zero in order to discourage
> using these negative-indexing macros.
>
> Signed-off-by: Peilin Ye <yepeilin.cs@xxxxxxxxx>
Patch looks good to me, but it says 1/2 and I can't find 2/2 anywhere,
not even on lore. Did that get lost?
-Daniel
> ---
> lib/fonts/font_6x8.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/lib/fonts/font_6x8.c b/lib/fonts/font_6x8.c
> index e06447788418..700039a9ceae 100644
> --- a/lib/fonts/font_6x8.c
> +++ b/lib/fonts/font_6x8.c
> @@ -3,8 +3,8 @@
>
> #define FONTDATAMAX 2048
>
> -static const unsigned char fontdata_6x8[FONTDATAMAX] = {
> -
> +static struct font_data fontdata_6x8 = {
> + { 0, 0, FONTDATAMAX, 0 }, {
> /* 0 0x00 '^@' */
> 0x00, /* 000000 */
> 0x00, /* 000000 */
> @@ -2564,13 +2564,13 @@ static const unsigned char fontdata_6x8[FONTDATAMAX] = {
> 0x00, /* 000000 */
> 0x00, /* 000000 */
> 0x00, /* 000000 */
> -};
> +} };
>
> const struct font_desc font_6x8 = {
> .idx = FONT6x8_IDX,
> .name = "6x8",
> .width = 6,
> .height = 8,
> - .data = fontdata_6x8,
> + .data = fontdata_6x8.data,
> .pref = 0,
> };
> --
> 2.25.1
>
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
