Memory Leak Affecting kernel-rt-debug package, versions *

Note: Versions mentioned in the description apply only to the upstream kernel-rt-debug package and not the kernel-rt-debug package as distributed by RHEL. See How to fix? for RHEL:7 relevant fixed versions and status.

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

i40e: Fix macvlan leak by synchronizing access to mac_filter_hash

This patch addresses a macvlan leak issue in the i40e driver caused by concurrent access to vsi->mac_filter_hash. The leak occurs when multiple threads attempt to modify the mac_filter_hash simultaneously, leading to inconsistent state and potential memory leaks.

To fix this, we now wrap the calls to i40e_del_mac_filter() and zeroing vf->default_lan_addr.addr with spin_lock/unlock_bh(&vsi->mac_filter_hash_lock), ensuring atomic operations and preventing concurrent access.

Additionally, we add lockdep_assert_held(&vsi->mac_filter_hash_lock) in i40e_add_mac_filter() to help catch similar issues in the future.

Reproduction steps:

1. Spawn VFs and configure port vlan on them.
2. Trigger concurrent macvlan operations (e.g., adding and deleting portvlan and/or mac filters).
3. Observe the potential memory leak and inconsistent state in the mac_filter_hash.

This synchronization ensures the integrity of the mac_filter_hash and prevents the described leak.

• https://access.redhat.com/security/cve/CVE-2024-50041
• https://git.kernel.org/stable/c/703c4d820b31bcadf465288d5746c53445f02a55
• https://git.kernel.org/stable/c/8831abff1bd5b6bc8224f0c0671f46fbd702b5b2
• https://git.kernel.org/stable/c/9a9747288ba0a9ad4f5c9877f18dd245770ad64e
• https://git.kernel.org/stable/c/9db6ce9e2738b05a3672aff4d42169cf3bb5a3e3
• https://git.kernel.org/stable/c/dac6c7b3d33756d6ce09f00a96ea2ecd79fae9fb