In the Linux kernel, the following vulnerability has been resolved:
s390/qeth: Fix kernel panic after setting hsuid
Symptom: When the hsuid attribute is set for the first time on an IQD Layer3 device while the corresponding network interface is already UP, the kernel will try to execute a napi function pointer that is NULL.
Analysis: There is one napi structure per out_q: card->qdio.out_qs[i].napi The napi.poll functions are set during qeth_open().
Since commit 1cfef80d4c2b ("s390/qeth: Don't call dev_close/dev_open (DOWN/UP)") qeth_set_offline()/qeth_set_online() no longer call dev_close()/ dev_open(). So if qeth_free_qdio_queues() cleared card->qdio.out_qs[i].napi.poll while the network interface was UP and the card was offline, they are not set again.
Reproduction: chzdev -e $devno layer2=0 ip link set dev $network_interface up echo 0 > /sys/bus/ccw ---truncated---
{
"cna_assigner": "Linux",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/36xxx/CVE-2024-36928.json"
}