CVE-2024-44964

In the Linux kernel, the following vulnerability has been resolved:

idpf: fix memory leaks and crashes while performing a soft reset

The second tagged commit introduced a UAF, as it removed restoring q_vector->vport pointers after reinitializating the structures. This is due to that all queue allocation functions are performed here with the new temporary vport structure and those functions rewrite the backpointers to the vport. Then, this new struct is freed and the pointers start leading to nowhere.

But generally speaking, the current logic is very fragile. It claims to be more reliable when the system is low on memory, but in fact, it consumes two times more memory as at the moment of running this function, there are two vports allocated with their queues and vectors. Moreover, it claims to prevent the driver from running into "bad state", but in fact, any error during the rebuild leaves the old vport in the partially allocated state. Finally, if the interface is down when the function is called, it always allocates a new queue set, but when the user decides to enable the interface later on, vport_open() allocates them once again, IOW there's a clear memory leak here.

Just don't allocate a new queue set when performing a reset, that solves crashes and memory leaks. Readd the old queue number and reopen the interface on rollback - that solves limbo states when the device is left disabled and/or without HW queues enabled.

This vulnerability is rated as Moderate because triggering the condition requires local administrative privileges to initiate network device resets, alongside the presence of specific Intel Infrastructure Data Path Function hardware. On typical Red Hat Enterprise Linux installations, the idpf driver is only utilized on systems configured with compatible Intel IPU adapters. A privileged user could exploit this flaw to cause a use-after-free state resulting in a kernel crash or instability, limiting the blast radius to a local denial of service.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.