CVE-2023-53123

In the Linux kernel, the following vulnerability has been resolved: PCI: s390: Fix use-after-free of PCI resources with per-function hotplug On s390 PCI functions may be hotplugged individually even when they belong to a multi-function device. In particular on an SR-IOV device VFs may be removed and later re-added. In commit a50297cf8235 ("s390/pci: separate zbus creation from scanning") it was missed however that struct pci_bus and struct zpci_bus's resource list retained a reference to the PCI functions MMIO resources even though those resources are released and freed on hot-unplug. These stale resources may subsequently be claimed when the PCI function re-appears resulting in use-after-free. One idea of fixing this use-after-free in s390 specific code that was investigated was to simply keep resources around from the moment a PCI function first appeared until the whole virtual PCI bus created for a multi-function device disappears. The problem with this however is that due to the requirement of artificial MMIO addreesses (address cookies) extra logic is then needed to keep the address cookies compatible on re-plug. At the same time the MMIO resources semantically belong to the PCI function so tying their lifecycle to the function seems more logical. Instead a simpler approach is to remove the resources of an individually hot-unplugged PCI function from the PCI bus's resource list while keeping the resources of other PCI functions on the PCI bus untouched. This is done by introducing pci_bus_remove_resource() to remove an individual resource. Similarly the resource also needs to be removed from the struct zpci_bus's resource list. It turns out however, that there is really no need to add the MMIO resources to the struct zpci_bus's resource list at all and instead we can simply use the zpci_bar_struct's resource pointer directly.

• CWE-416

• https://git.kernel.org/stable/c/437bb839e36cc9f35adc6d2a2bf113b7a0fc9985Patch
• https://git.kernel.org/stable/c/a2410d0c3d2d714ed968a135dfcbed6aa3ff7027Patch
• https://git.kernel.org/stable/c/ab909509850b27fd39b8ba99e44cda39dbc3858cPatch
• https://git.kernel.org/stable/c/b99ebf4b62774e690e73a551cf5fbf6f219bdd96Patch

Published

May 2, 2025

Last Modified

Jun 17, 2026

Status

Analyzed

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
• Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
• PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
• AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.

• CVE-2023-53118In the Linux kernel, the following vulnerability has been re…5.5
• CVE-2023-53119In the Linux kernel, the following vulnerability has been re…5.5
• CVE-2023-5312Rejected reason: ** REJECT ** DO NOT USE THIS CANDIDATE NUMB…
• CVE-2023-53120In the Linux kernel, the following vulnerability has been re…5.5
• CVE-2023-53121In the Linux kernel, the following vulnerability has been re…5.5
• CVE-2023-53122Rejected reason: This CVE ID has been rejected or withdrawn …
• CVE-2023-53124In the Linux kernel, the following vulnerability has been re…5.5
• CVE-2023-53125In the Linux kernel, the following vulnerability has been re…5.5
• CVE-2023-53126In the Linux kernel, the following vulnerability has been re…5.5
• CVE-2023-53127In the Linux kernel, the following vulnerability has been re…5.5
• CVE-2023-53128In the Linux kernel, the following vulnerability has been re…5.5
• CVE-2023-53129Rejected reason: This CVE ID has been rejected or withdrawn …