Description: bpf: fix incorrect tracking of register size truncation
References:
 https://bugs.chromium.org/p/project-zero/issues/detail?id=1454
 http://www.openwall.com/lists/oss-security/2017/12/21/2
Notes:
 carnil> Introduced in 4.14-rc1 with b03c9f9fdc37dab81ea04d5dacdc5995d4c224c2
Bugs:
upstream: released (4.15-rc5) [0c17d1d2c61936401f4702e1846e2c19b200f958]
4.9-upstream-stable: N/A "Vulnerable code introduced in 4.14-rc1"
3.16-upstream-stable: N/A "Vulnerable code introduced in 4.14-rc1"
3.2-upstream-stable: N/A "Vulnerable code introduced in 4.14-rc1"
sid: released (4.14.7-1) [bugfix/all/bpf-fix-incorrect-tracking-of-register-size-truncati.patch]
4.9-stretch-security: N/A "Vulnerable code introduced later"
3.16-jessie-security: N/A "Vulnerable code introduced later"
3.2-wheezy-security: N/A "Vulnerable code introduced later"