CVE-2010-3081

The compat_alloc_user_space functions in include/asm/compat.h files in the Linux kernel before 2.6.36-rc4-git2 on 64-bit platforms do not properly allocate the userspace memory required for the 32-bit compatibility layer, which allows local users to gain privileges by leveraging the ability of the compat_mc_getsockopt function (aka the MCAST_MSFILTER getsockopt support) to control a certain length value, related to a "stack pointer underflow" issue, as exploited in the wild in September 2010.

The compat_alloc_user_space functions in include/asm/compat.h files in the Linux kernel before 2.6.36-rc4-git2 on 64-bit platforms do not properly allocate the userspace memory required for the 32-bit compatibility layer, which allows local users to gain privileges by leveraging the ability of the compat_mc_getsockopt function (aka the MCAST_MSFILTER getsockopt support) to control a certain length value, related to a "stack pointer underflow" issue, as exploited in the wild in September 2010.

Las funciones compat_alloc_user_space en los ficheros include/asm/compat.h del kernel de Linux en versiones anteriores a la v2.6.36-rc4-git2 en plataformas de 64-bit no reservan adecuadamente la memoria del espacio de usuario requerida para la capa de compatibilidad de 32-bit, lo que permite a usuarios locales escalar privilegios basándose en la capacidad de la función compat_mc_getsockopt (también conocido como soporte MCAST_MSFILTER getsockopt) para controlar un valor de longitud determinado, relacionado con un "stack pointer underflow", como se ha demostrado en septiembre del 2010.