979d63d50c0c0f7bc537bf821e056cc9fe5abd38 bpf: prevent out of bounds speculation on pointer arithmetic

[Jason Yan]

Hi, Daniel & Greg

This patch (979d63d50c0c bpf: prevent out of bounds speculation on 
pointer arithmetic) was assigned a CVE (CVE-2019-7308) with a high score:

CVSS v3.0 Severity and Metrics:
Base Score: 9.8 CRITICAL

And this patch is not in stable-4.4, would you please backport this 
patch to 4.4?

Thanks,
Jason