In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Avoid race between dcn10setdrr() and dcstatedestruct()
dcstatedestruct() nulls the resource context of the DC state. The pipe context passed to dcn10setdrr() is a member of this resource context.
If dcstatedestruct() is called parallel to the IRQ processing (which calls dcn10setdrr() at some point), we can end up using already nulled function callback fields of struct stream_resource.
The logic in dcn10setdrr() already tries to avoid this, by checking tg against NULL. But if the nulling happens exactly after the NULL check and before the next access, then we get a race.
Avoid this by copying tg first to a local variable, and then use this variable for all the operations. This should work, as long as nobody frees the resource pool where the timing generators live.
(cherry picked from commit a3cc326a43bdc48fbdf53443e1027a03e309b643)