The agp_generic_remove_memory function in drivers/char/agp/generic.c in the Linux kernel before 2.6.38.5 does not validate a certain start parameter, which allows local users to gain privileges or cause a denial of service (system crash) via a crafted AGPIOC_UNBIND agp_ioctl ioctl call, a different vulnerability than CVE-2011-1745.
Improper Input Validation The product receives input or data, but it does
not validate or incorrectly validates that the input has the
properties that are required to process the data safely and
correctly.