CVE-2026-98476: s390/cio: Fix NULL pointer dereference in ccw_device_get_util_str()

Severity: unknown
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-10-18 · updated 2026-10-19

Description

In the Linux kernel, the following vulnerability has been resolved: s390/cio: Fix NULL pointer dereference in ccw_device_get_util_str() The channel path registry entry associated with a CHPID may be removed while the subchannel's PMCW still references that CHPID. In this case, chpid_to_chp() can return NULL, leading to a NULL pointer dereference. Add the missing NULL check before dereferencing the returned pointer.

Affected products

Linux kernel: 4.18 — fixed in 7.3

How to fix

Upgrade to a fixed version: Linux kernel 7.3. Check the vendor advisory for mitigations.

References

https://git.kernel.org/stable/c/27e396a89f76f742abdbe9f8c4a58a6e806fdf59
https://git.kernel.org/stable/c/44b16b02608058fc72198ac0205969f0f43065df
https://git.kernel.org/stable/c/5b76268dac968612f7283d59b539036de955b7d9
https://git.kernel.org/stable/c/5e006ac90a4d331db1dd712b91fec849b45ffc01
https://git.kernel.org/stable/c/5fc54e04dad90b15d0430118b3f288a1d64e66c9
https://git.kernel.org/stable/c/9d8b21820caed9128945fffcedf03e2a4c21eee2
https://git.kernel.org/stable/c/c3bbcb32deecc06ebb1762398399b566d5ff2fc9
https://git.kernel.org/stable/c/dbf30e661ceb9a52c94c85719716391dcc29142a

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