Affected: Linux

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

drm/panthor: validate userspace queue count against initialized firmware slot count

In panthor_drv.c:panthor_ioctl_group_create(), the queue count is validated against the hardcoded maximum:

if (!args->queues.count || args->queues.count > MAX_CS_PER_CSG) return -EINVAL;

However, if the firmware reports fewer slots than MAX_CS_PER_CSG, panthor_fw_init_ifaces() will only initialize that smaller number of stream interfaces.

If unprivileged userspace requests more queues than the firmware reported (but no more than MAX_CS_PER_CSG), cs_slot_prog_locked() fetches an uninitialized stream interface and may crash when dereferencing cs_iface->input->ringbuf_base.