The Linux kernel is a cornerstone of numerous operating systems and devices worldwide and ensures everything runs smoothly. As with any complex software, vulnerabilities may sometimes appear, and developers must identify and address them. One such vulnerability, named CVE-2024-56699, has recently been resolved in the Linux kernel.
The vulnerability affected the s390/pci component of the kernel, posing a threat of a potential double removal of the hotplug slot. The problematic code was introduced in a previous commit (6ee600bfbef) with the purpose of keeping the hotplug slot available until the device is removed entirely. However, this introduced a scenario in which theslot might be removed twice.
Fortunately, the potential double removal impact of CVE-2024-56699 has been addressed by adding a WARN_ON() if a device in non-reserved state is released. As a result, the dead code cases in the zpci_release_device() function have been eliminated from the kernel.
Here is a code snippet showcasing the changes
void zpci_release_device(struct device *dev)
{
struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
zpci_exit_slot(zdev);
zpci_cleanup_device(zdev);
zpci_free_device(zdev);
}
For reference, you can find the original commit and the corresponding discussion on the Linux kernel mailing list here:
- Original Commit 6ee600bfbef
- Linux Kernel Mailing List Discussion
If you're using Linux, it's crucial to keep your kernel updated, especially when a resolved vulnerability involves the potential for a double removal of hotplug slots. To maintain a secure environment and prevent possible issues, always use the latest Linux kernel releases and follow the development of new patches and fixes.
Timeline
Published on: 12/28/2024 10:15:17 UTC
Last modified on: 01/20/2025 06:26:26 UTC