CVE-2011-2525

La función qdisc_notify de net/sched/sch_api.c del kernel de Linux en versiones anteriores a la 2.6.35 no previene que la función tc_fill_qdisc haga referencia a estructuras Qdisc (CQ_F_BUILTIN) pre-construídas, lo que permite a usuarios locales provocar una denegación de servicio (resolución de puntero NULL y OOPS) o posiblemente tener otros impactos sin especificar a través de una llamada modificada.

The kernel packages contain the Linux kernel, the core of any Linux operating system. This update includes backported fixes for two security issues. These issues only affected users of Red Hat Enterprise Linux 5.6 Extended Update Support, as they have already been addressed for users of Red Hat Enterprise Linux 5 in the 5.7 update, RHSA-2011:1065. A flaw was found in the way the Xen hypervisor implementation handled instruction emulation during virtual machine exits. A malicious user-space process running in an SMP guest could trick the emulator into reading a different instruction than the one that caused the virtual machine to exit. An unprivileged guest user could trigger this flaw to crash the host. This only affects systems with both an AMD x86 processor and the AMD Virtualization extensions enabled.