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by LtWorf 324 days ago
a segfault is completely unintentional. Had the kernel been older it could be used to execute code.
1 comments
zbentley 324 days ago
> a segfault is completely unintentional

Usually, but not always! https://jcdav.is/2015/10/06/SIGSEGV-as-control-flow/

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gowld 323 days ago
> Faulted trying to access 0x10 - the offset in the string we were trying to read from :)

Is guaranteed that every offset you can try to read is guaranteed to create a segfault?

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cesarb 323 days ago
> Is guaranteed that every offset you can try to read is guaranteed to create a segfault?

The offset is fixed as part of the compiled code; the JVM can enforce that it's less than 4k (otherwise it can use an explicit NULL check), and that the first 4k page is always unmapped.

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