vzkernel before 042stab080.2 in the OpenVZ modification for the Linux kernel 2.6.32 does not initialize certain length variables, which allows local users to obtain sensitive information from kernel stack memory via (1) a crafted ploop driver ioctl call, related to the ploop_getdevice_ioc function in drivers/block/ploop/dev.c, or (2) a crafted quotactl system call, related to the compat_quotactl function in fs/quota/quota.c.