[PATCH 0/2] wireguard-linux-compat: grsecurity compat patches

[Jason A. Donenfeld]

Hey Mathias,

This resulted in kind of an interesting regression with old compilers
on old kernel versions when I backported this to
wireguard-linux-compat:
https://git.zx2c4.com/wireguard-linux-compat/commit/?id=8118c247a75ae95169f0a9a539dfc661ffda8bc5

The 25519 tests fail for 4.8.17, 4.7.10, 4.6.7, 4.5.7 with gcc 6:

https://build.wireguard.com/wireguard-linux-compat/e8db181d62467da6c476cf4ac21e13dd477612c8/4.8.17-x86_64.log
https://build.wireguard.com/wireguard-linux-compat/e8db181d62467da6c476cf4ac21e13dd477612c8/4.7.10-x86_64.log
https://build.wireguard.com/wireguard-linux-compat/e8db181d62467da6c476cf4ac21e13dd477612c8/4.6.7-x86_64.log
https://build.wireguard.com/wireguard-linux-compat/e8db181d62467da6c476cf4ac21e13dd477612c8/4.5.7-x86_64.log

But then they crash for 4.0.9, 3.19.8, 3.17.8 with gcc 5:

https://build.wireguard.com/wireguard-linux-compat/e8db181d62467da6c476cf4ac21e13dd477612c8/4.0.9-x86_64.log
https://build.wireguard.com/wireguard-linux-compat/e8db181d62467da6c476cf4ac21e13dd477612c8/3.19.8-x86_64.log
https://build.wireguard.com/wireguard-linux-compat/e8db181d62467da6c476cf4ac21e13dd477612c8/3.17.8-x86_64.log

And also crash with 3.16.85, 3.15.10, 3.14.79, 3.12.74, 3.11.10 with gcc 4:

https://build.wireguard.com/wireguard-linux-compat/e8db181d62467da6c476cf4ac21e13dd477612c8/3.16.85-x86_64.log
https://build.wireguard.com/wireguard-linux-compat/e8db181d62467da6c476cf4ac21e13dd477612c8/3.15.10-x86_64.log
https://build.wireguard.com/wireguard-linux-compat/e8db181d62467da6c476cf4ac21e13dd477612c8/3.14.79-x86_64.log
https://build.wireguard.com/wireguard-linux-compat/e8db181d62467da6c476cf4ac21e13dd477612c8/3.13.11-x86_64.log
https://build.wireguard.com/wireguard-linux-compat/e8db181d62467da6c476cf4ac21e13dd477612c8/3.12.74-x86_64.log
https://build.wireguard.com/wireguard-linux-compat/e8db181d62467da6c476cf4ac21e13dd477612c8/3.11.10-x86_64.log

Any intuition about what might have happened?

Jason