Commit 0975670c authored Apr 04, 2023 by Daniel Vetter Committed by Greg Kroah-Hartman Sep 04, 2024

drm/fb-helper: set x/yres_virtual in drm_fb_helper_check_var



commit 1935f0deb6116dd785ea64d8035eab0ff441255b upstream.

Drivers are supposed to fix this up if needed if they don't outright
reject it. Uncovered by 6c11df58fd1a ("fbmem: Check virtual screen
sizes in fb_set_var()").

Reported-by:  <syzbot+20dcf81733d43ddff661@syzkaller.appspotmail.com>
Link: https://syzkaller.appspot.com/bug?id=c5faf983bfa4a607de530cd3bb008888bf06cefc


Cc: stable@vger.kernel.org # v5.4+
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230404194038.472803-1-daniel.vetter@ffwll.ch


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 72793f5c

drivers/gpu/drm/drm_fb_helper.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -1713,6 +1713,9 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
		return -EINVAL;
		}

		var->xres_virtual = fb->width;
		var->yres_virtual = fb->height;

		/*
		* Workaround for SDL 1.2, which is known to be setting all pixel format
		* fields values to zero in some cases. We treat this situation as a