# CVE-2024-36928: s390/qeth: Fix kernel panic after setting hsuid

> A null pointer dereference in the s390/qeth driver causes a kernel panic when setting the hsuid attribute on an active IQD Layer3 device.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 30 May 2024
- **Updated:** 5 Aug 2026
- **Also known as:** BELL-CVE-2024-36928, DEBIAN-CVE-2024-36928, ROOT-OS-DEBIAN-11-CVE-2024-36928, UBUNTU-CVE-2024-36928

## What is CVE-2024-36928?

CVE-2024-36928 is a high-severity vulnerability in Linux kernel, published on 30 May 2024. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

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.

Example:
---------------------------------------------------------------------------
[ 2057.572696] illegal operation: 0001 ilc:1 [#1] SMP
[ 2057.572702] Modules linked in: af_iucv qeth_l3 zfcp scsi_transport_fc sunrpc nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6
nft_reject nft_ct nf_tables_set nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set nf_tables libcrc32c nfnetlink ghash_s390 prng xts aes_s390 des_s390 de
s_generic sha3_512_s390 sha3_256_s390 sha512_s390 vfio_ccw vfio_mdev mdev vfio_iommu_type1 eadm_sch vfio ext4 mbcache jbd2 qeth_l2 bridge stp llc dasd_eckd_mod qeth dasd_mod
 qdio ccwgroup pkey zcrypt
[ 2057.572739] CPU: 6 PID: 60182 Comm: stress_client Kdump: loaded Not tainted 4.18.0-541.el8.s390x #1
[ 2057.572742] Hardware name: IBM 3931 A01 704 (LPAR)
[ 2057.572744] Krnl PSW : 0704f00180000000 0000000000000002 (0x2)
[ 2057.572748]            R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[ 2057.572751] Krnl GPRS: 0000000000000004 0000000000000000 00000000a3b008d8 0000000000000000
[ 2057.572754]            00000000a3b008d8 cb923a29c779abc5 0000000000000000 00000000814cfd80
[ 2057.572756]            000000000000012c 0000000000000000 00000000a3b008d8 00000000a3b008d8
[ 2057.572758]            00000000bab6d500 00000000814cfd80 0000000091317e46 00000000814cfc68
[ 2057.572762] Krnl Code:#0000000000000000: 0000                illegal
                         >0000000000000002: 0000                illegal
                          0000000000000004: 0000                illegal
                          0000000000000006: 0000                illegal
                          0000000000000008: 0000                illegal
                          000000000000000a: 0000                illegal
                          000000000000000c: 0000                illegal
                          000000000000000e: 0000                illegal
[ 2057.572800] Call Trace:
[ 2057.572801] ([<00000000ec639700>] 0xec639700)
[ 2057.572803]  [<00000000913183e2>] net_rx_action+0x2ba/0x398
[ 2057.572809]  [<0000000091515f76>] __do_softirq+0x11e/0x3a0
[ 2057.572813]  [<0000000090ce160c>] do_softirq_own_stack+0x3c/0x58
[ 2057.572817] ([<0000000090d2cbd6>] do_softirq.part.1+0x56/0x60)
[ 2057.572822]  [<0000000090d2cc60>] __local_bh_enable_ip+0x80/0x98
[ 2057.572825]  [<0000000091314706>] __dev_queue_xmit+0x2be/0xd70
[ 2057.572827]  [<000003ff803dd6d6>] afiucv_hs_send+0x24e/0x300 [af_iucv]
[ 2057.572830]  [<000003ff803dd88a>] iucv_send_ctrl+0x102/0x138 [af_iucv]
[ 2057.572833]  [<000003ff803de72a>] iucv_sock_connect+0x37a/0x468 [af_iucv]
[ 2057.572835]  [<00000000912e7e90>] __sys_connect+0xa0/0xd8
[ 2057.572839]  [<00000000912e9580>] sys_socketcall+0x228/0x348
[ 2057.572841]  [<0000000091514e1a>] system_call+0x2a6/0x2c8
[ 2057.572843] Last Breaking-Event-Address:
[ 2057.572844]  [<0000000091317e44>] __napi_poll+0x4c/0x1d8
[ 2057.572846]
[ 2057.572847] Kernel panic - not syncing: Fatal exception in interrupt
-------------------------------------------------------------------------------------------

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---

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2024-36928?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-36928?

Apply the vendor's patch.

## Is CVE-2024-36928 being exploited?

There is no known exploitation of CVE-2024-36928 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-36928 and fix it if it is affected.

What it is: CVE-2024-36928 is a high-severity vulnerability in Linux kernel, published on 30 May 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2024-36928 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2024-36928/ (Markdown: https://insights.sbomify.com/CVE-2024-36928/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-36928
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-36928
- OSV: https://osv.dev/vulnerability/CVE-2024-36928

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-36928/
Summaries are generated and may contain mistakes; the official description above is the record.
