It got traced to a race condition in munmap() in the kernel. The inefficient musl allocator simply triggers it more easily.
It got arm-waved to a race condition in munmap(). Claude (or a distill of Claude) didn't identify a race, it just convinced itself that was the cause.
Andy Lutomirski seems to think that it is a bug: https://lore.kernel.org/all/CALCETrXbj__SFQMzPZhES5y6-sh4np-...
I looked at the explanation, and it seems to be at very least plausible. The kernel version bisection also lines up. We'll see if the proposed patch fixes this.
It got arm-waved to a race condition in munmap(). Claude (or a distill of Claude) didn't identify a race, it just convinced itself that was the cause.
Andy Lutomirski seems to think that it is a bug: https://lore.kernel.org/all/CALCETrXbj__SFQMzPZhES5y6-sh4np-...
I looked at the explanation, and it seems to be at very least plausible. The kernel version bisection also lines up. We'll see if the proposed patch fixes this.