@david_chisnall Since the blog that describes the exploitation process recommends memory_limit = -1 (disabled) as a mitigation if patching is not possible, I was thinking whether it would make sense as a defense-in-depth measure to run with the internal memory_limit disabled all the time. Instead set up rlimits or cgroups or whatever to immediately kill off workers that hit the limit.

I don't deal in php much and this probably isn't suited to all installations, but in theory this feels like it should eliminate a class of vulnerabilities stemming from retroactively implemented OOM recovery. @GossiTheDog

(edit: turns out that convincing Linux to JUST KILL THE FUCKING PROCESS DO NOT SEND ENOMEM DO NOT TRY ANYTHING without resorting to LD_PRELOAD tricks is hard, setting both memory.max and memory.swap.max maybe kinda does it?)