A certain Red Hat patch for net/ipv4/route.c in the Linux kernel 2.6.18 on Red Hat Enterprise Linux (RHEL) 5 allows remote attackers to cause a denial of service (deadlock) via crafted packets that force collisions in the IPv4 routing hash table, and trigger a routing emergency in which a hash chain is too long. NOTE: this is related to an issue in the Linux kernel before 2.6.31, when the kernel routing cache is disabled, involving an uninitialized pointer and a panic.
The product does not properly acquire or release a lock on a resource, leading to unexpected resource state changes and behaviors.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Linux_kernel | Linux | 2.6.18 (including) | 2.6.18 (including) |
| Red Hat Enterprise Linux 5 | RedHat | kernel-0:2.6.18-164.11.1.el5 | * |
| Red Hat Enterprise Virtualization for RHEL-5 | RedHat | rhev-hypervisor-0:5.4-2.1.8.el5_4rhev2_1 | * |
| Linux | Ubuntu | upstream | * |
| Linux-source-2.6.15 | Ubuntu | upstream | * |
Locking is a type of synchronization behavior that ensures that multiple independently-operating processes or threads do not interfere with each other when accessing the same resource. All processes/threads are expected to follow the same steps for locking. If these steps are not followed precisely - or if no locking is done at all - then another process/thread could modify the shared resource in a way that is not visible or predictable to the original process. This can lead to data or memory corruption, denial of service, etc.