Messages in this thread | | | From | Sven Van Asbroeck <> | Date | Tue, 5 Feb 2019 10:22:50 -0500 | Subject | Re: [RFC v1 0/3] Address potential user-after-free on module unload |
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On Tue, Feb 5, 2019 at 9:57 AM Kees Cook <keescook@chromium.org> wrote: > > > Can a Coccinelle script get written to find module-use of the non-devm > work init?
My thoughts exactly ! But sadly I'm not a Coccinelle expert. I did look briefly at its syntax, but I didn't immediately "get" how Cocci could find this class of errors, without a huge false positive rate (which would make it worse than useless).
> > It seems like finding these in __init functions should be relatively > easy? (Or can we add runtime detection in the existing INIT_*WORK() > code to see if it is running from the wrong place?) >
IMHO the problem isn't that they're called from __init functions. Also, nothing is wrong with the location of INIT_*WORK per se.
The real problem is that developers overlook calling cancel_work_sync() on unload. I'm not sure how we could bolt on runtime detection to catch a *missing* function. Again, without causing tons of false positives.
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