CVE-2017-9150

La función do_check en el archivo kernel/bpf/verifier.c en el kernel de Linux anterior a versión 4.11.1, no hace que el valor de allow_ptr_leaks esté disponible para restringir la salida de la función print_bpf_insn, que permite a los usuarios locales obtener información de una dirección confidencial por medio de llamadas del sistema bpf especialmente diseñadas.

It was discovered that a use-after-free flaw existed in the filesystem encryption subsystem in the Linux kernel. A local attacker could use this to cause a denial of service (system crash). Jann Horn discovered that the extended Berkeley Packet Filter (eBPF) implementation in the Linux kernel could overflow reference counters on systems with more than 32GB of physical ram and with RLIMIT_MEMLOCK set to infinite. A local unprivileged attacker could use to create a use-after- free situation, causing a denial of service (system crash) or possibly gain administrative privileges. Various other issues were also addressed.