Daniel Vetter 3ea7f138ce drm/vgem: Close use-after-free race in vgem_gem_create ... commit 4b848f20ed upstream. There's two references floating around here (for the object reference, not the handle_count reference, that's a different thing): - The temporary reference held by vgem_gem_create, acquired by creating the object and released by calling drm_gem_object_put_unlocked. - The reference held by the object handle, created by drm_gem_handle_create. This one generally outlives the function, except if a 2nd thread races with a GEM_CLOSE ioctl call. So usually everything is correct, except in that race case, where the access to gem_object->size could be looking at freed data already. Which again isn't a real problem (userspace shot its feet off already with the race, we could return garbage), but maybe someone can exploit this as an information leak. Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Hillf Danton <hdanton@sina.com> Reported-by: syzbot+0dc4444774d419e916c8@syzkaller.appspotmail.com Cc: stable@vger.kernel.org Cc: Emil Velikov <emil.velikov@collabora.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Sean Paul <seanpaul@chromium.org> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Eric Anholt <eric@anholt.net> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Rob Clark <robdclark@chromium.org> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200202132133.1891846-1-daniel.vetter@ffwll.ch Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2020-02-19 19:53:04 +01:00
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Makefile	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
vgem_drv.c	drm/vgem: Close use-after-free race in vgem_gem_create	2020-02-19 19:53:04 +01:00
vgem_drv.h	drm/vgem: drop use of drmP.h	2019-07-17 12:52:55 +02:00
vgem_fence.c	dma-buf: rename reservation_object to dma_resv	2019-08-13 09:09:30 +02:00