From: Daniel Vetter <daniel.vetter@xxxxxxxx>
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@xxxxxxxxxxxxxxxxxxxxxxxxx
Link: https://syzkaller.appspot.com/bug?id=c5faf983bfa4a607de530cd3bb008888bf06cefc
Cc: stable@xxxxxxxxxxxxxxx # v5.4+
Cc: Daniel Vetter <daniel@xxxxxxxx>
Cc: Javier Martinez Canillas <javierm@xxxxxxxxxx>
Cc: Thomas Zimmermann <tzimmermann@xxxxxxx>
Reviewed-by: Javier Martinez Canillas <javierm@xxxxxxxxxx>
Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20230404194038.472803-1-daniel.vetter@xxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/drm_fb_helper.c | 3 +++
1 file changed, 3 insertions(+)
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -1406,6 +1406,9 @@ int drm_fb_helper_check_var(struct fb_va
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
