Describe CVE-2021-47207.
What is CVE-2021-47207?
In the Linux kernel, the following vulnerability has been resolved:

ALSA: gus: fix null pointer dereference on pointer block

The pointer block return from snd_gf1_dma_next_block could be
null, so there is a potential null pointer dereference issue.
Fix this by adding a null check before dereference..