Description: bpf: don't let ldimm64 leak map addresses on unprivileged
References:
 https://bugs.chromium.org/p/project-zero/issues/detail?id=1251
Notes:
 carnil> Commit fixes 1be7f75d1668 (4.4-rc1) and cbd357008604 (3.18-rc1)
Bugs:
upstream: released (4.12-rc1) [0d0e57697f162da4aa218b5feafe614fb666db07]
4.9-upstream-stable: released (4.9.28) [ced0a31e667fbf618591f0a76a8213018407cde0]
3.16-upstream-stable: N/A "Vulnerable code introduced later"
3.2-upstream-stable: N/A "Vulnerable code introduced later"
sid: released (4.9.30-1)
3.16-jessie-security: N/A "Vulnerable code not present"
3.2-wheezy-security: N/A "Vulnerable code not present"