mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-05 10:29:37 +00:00
drm/fb: Stop leaking physical address
For buffer sharing, use dma-buf instead. We can't set smem_start to 0 unconditionally since that's used by the fbdev mmap default implementation. And we have plenty of userspace which would like to keep that working. This might break legit userspace - if it does we need to look at a case-by-cases basis how to handle that. Worst case I expect overrides for only specific drivers, since anything remotely modern should be using dma-buf/prime now (which is about 7 years old now for DRM drivers). This issue was uncovered because Noralf's rework to implement a generic fb_probe also implements it's own fb_mmap callback. Which means smem_start didn't have to be set anymore, which blew up some blob in userspace rather badly. Acked-by: Sean Paul <seanpaul@chromium.org> Cc: Gustavo Padovan <gustavo@padovan.org> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Sean Paul <sean@poorly.run> Cc: David Airlie <airlied@linux.ie> Cc: John Stultz <john.stultz@linaro.org> Cc: Noralf Trønnes <noralf@tronnes.org> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20180822085405.10787-4-daniel.vetter@ffwll.ch
This commit is contained in:
parent
da6c7707ca
commit
6be8f3bd2c
1 changed files with 2 additions and 0 deletions
|
@ -2673,6 +2673,8 @@ __drm_fb_helper_initial_config_and_unlock(struct drm_fb_helper *fb_helper,
|
|||
|
||||
info = fb_helper->fbdev;
|
||||
info->var.pixclock = 0;
|
||||
/* don't leak any physical addresses to userspace */
|
||||
info->flags |= FBINFO_HIDE_SMEM_START;
|
||||
|
||||
/* Need to drop locks to avoid recursive deadlock in
|
||||
* register_framebuffer. This is ok because the only thing left to do is
|
||||
|
|
Loading…
Reference in a new issue