Red Hat Security Advisory: kernel security update

Moderate

A vulnerability was found in the del_timer() function in the Linux kernel's watchdog driver. This issue occurs because the function does not wait for the timer handler to finish, which may lead to a situation where the handler runs after the driver that has been removed, causing a use-after-free issue.

CWE-416 - Use After Free

A vulnerability was found in the Linux kernel's mlxsw spectrum driver, where processing port up/down events leads to a NULL pointer dereference. This issue occurs when the driver fails to handle events for the CPU port, which exists but lacks a corresponding network device, resulting in system crashes.

CWE-476 - NULL Pointer Dereference

A use-after-free flaw was found in the Linux kernel’s Ext4 File System in how a user triggers several file operations simultaneously with the overlay FS usage. This flaw allows a local user to crash or potentially escalate their privileges on the system. Only if patch 9a2544037600 ("ovl: fix use after free in struct ovl_aio_req") not applied yet, the kernel could be affected.

CWE-416 - Use After Free

CVE-2024-35884 highlights a flaw in the Linux kernel's handling of UDP packets when Generic Receive Offload (GRO) forwarding is enabled. The issue occurs because non-tunnel UDP packets are sometimes mistakenly processed as if they belong to a tunnel. This can lead to data corruption or kernel crashes, particularly in environments with complex network configurations or when certain tunneling protocols like Geneve are used. The kernel's processing logic for GRO and UDP packets fails to properly differentiate between tunneled and non-tunneled packets. As a result, improperly handled packets may lead to segmentation errors or system instability. This vulnerability affects system availability and could result in crashes or data integrity issues during packet forwarding.