Re: [PATCH] zero-fill colormap in drivers/video/fbdev/core/fbcmap.c

On Thu, Apr 01, 2021 at 11:55:50AM +0200, Geert Uytterhoeven wrote:

On Thu, Apr 1, 2021 at 12:09 AM Phillip Potter [off-list ref] wrote:

quoted

Use kzalloc() rather than kmalloc() for the dynamically allocated parts
of the colormap in fb_alloc_cmap_gfp, to prevent a leak of random kernel
data to userspace under certain circumstances.

Fixes a KMSAN-found infoleak bug reported by syzbot at:
https://syzkaller.appspot.com/bug?id=741578659feabd108ad9e06696f0c1f2e69c4b6e

Reported-by: syzbot+47fa9c9c648b765305b9@syzkaller.appspotmail.com
Signed-off-by: Phillip Potter <phil@philpotter.co.uk>

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Dear Geert

Thank you for your review :-)

Regards,
Phil