CVE-2026-43217

In the Linux kernel, the following vulnerability has been resolved:

media: iris: gen2: Add sanity check for session stop

In iris_kill_session, inst->state is set to IRIS_INST_ERROR and
session_close is executed, which will kfree(inst_hfi_gen2->packet).
If stop_streaming is called afterward, it will cause a crash.

Add a NULL check for inst_hfi_gen2->packet before sendling STOP packet
to firmware to fix that.