CVE-2024-26620High· 8.2▾ TwilightIn the Linux kernel, the following vulnerability has been resolved: s390/vfio-ap: always filter entire AP matrix The vfio_ap_mdev_filter_matrix function is called whenever a new adapter or domain is assigned to the mdev. The purpose of…
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 45.1 · likelihood 0.1 · exploitation 0
Need a working PoC? Pro members can cast a request and our team develops one — it lands right here.
Exploit-prediction probability, daily snapshots since Aug 5.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
Last analysed / modified upstream
0.6%
In the Linux kernel, the following vulnerability has been resolved:
s390/vfio-ap: always filter entire AP matrix
The vfio_ap_mdev_filter_matrix function is called whenever a new adapter or domain is assigned to the mdev. The purpose of the function is to update the guest's AP configuration by filtering the matrix of adapters and domains assigned to the mdev. When an adapter or domain is assigned, only the APQNs associated with the APID of the new adapter or APQI of the new domain are inspected. If an APQN does not reference a queue device bound to the vfio_ap device driver, then it's APID will be filtered from the mdev's matrix when updating the guest's AP configuration.
Inspecting only the APID of the new adapter or APQI of the new domain will result in passing AP queues through to a guest that are not bound to the vfio_ap device driver under certain circumstances. Consider the following:
guest's AP configuration (all also assigned to the mdev's matrix): 14.0004 14.0005 14.0006 16.0004 16.0005 16.0006
unassign domain 4 unbind queue 16.0005 assign domain 4
When domain 4 is re-assigned, since only domain 4 will be inspected, the APQNs that will be examined will be: 14.0004 16.0004
Since both of those APQNs reference queue devices that are bound to the vfio_ap device driver, nothing will get filtered from the mdev's matrix when updating the guest's AP configuration. Consequently, queue 16.0005 will get passed through despite not being bound to the driver. This violates the linux device model requirement that a guest shall only be given access to devices bound to the device driver facilitating their pass-through.
To resolve this problem, every adapter and domain assigned to the mdev will be inspected when filtering the mdev's matrix.
linux_kernel >= 6.0, < 6.1.76linux_kernel >= 6.2, < 6.6.15linux_kernel >= 6.7, < 6.7.3Upgrade past the affected range:
linux_kernel 6.7.3Connected by shared product, vendor, weakness, or advisory.
CVE-2022-0995High· 7.8An out-of-bounds (OOB) memory write flaw was found in the Linux kernel’s watch_queue event notification subsystem
CVE-2021-4090High· 7.1An out-of-bounds (OOB) memory write flaw was found in the NFSD in the Linux kernel
CVE-2023-6931High· 7.8A heap out-of-bounds write vulnerability in the Linux kernel's Performance Events system component can be exploited to achieve local privilege escalation. A perf_event's read_size can overflow, leading to an heap out-of-bounds increme…
CVE-2023-42753High· 7.0An array indexing vulnerability was found in the netfilter subsystem of the Linux kernel
CVE-2021-38166High· 7.8In kernel/bpf/hashtab.c in the Linux kernel through 5.13.8, there is an integer overflow and out-of-bounds write when many elements are placed in a single bucket
CVE-2026-31710Medium· 5.5In the Linux kernel, the following vulnerability has been resolved: smb: client: fix dir separator in SMB1 UNIX mounts When calling cifs_mount_get_tcon() with SMB1 UNIX mounts, @cifs_sb->mnt_cifs_flags needs to be read or updated only …