Randomize mach_override_ptr trampoline addresses on 32-bit

Randomize mach_override_ptr trampoline addresses on 32-bit

BUG=265731
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=217238

[ianbeer, 2013-08-12 13:40:22]

This randomizes the locations of the mach_override_ptr trampolines on 32 bit.

Doing it for 64 bit is more complicated as the hooking is done with a relative
jmp instruction limiting you to +- 2G from the hooked function to the trampoline
so just setting VM_FLAGS_ANYWHERE won't work.

[Mark Mentovai, 2013-08-12 14:13:22]

LGTM

[commit-bot: I haz the power, 2013-08-12 14:18:06]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/ianbeer@chromium.org/22798004/5001

[commit-bot: I haz the power, 2013-08-12 18:15:02]

Retried try job too often on win_rel for step(s) browser_tests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win_rel&nu...

[commit-bot: I haz the power, 2013-08-13 07:55:04]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/ianbeer@chromium.org/22798004/5001

[commit-bot: I haz the power, 2013-08-13 11:53:46]

Change committed as 217238

[Mark Mentovai, 2013-11-06 02:57:15]

This hasn’t been upstreamed to https://github.com/rentzsch/mach_override yet.
Please upstream it.