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Subject: Re: WARNING in rfkill_alloc
From: Johannes Berg <johannes@sipsolutions.net>
To: Dmitry Vyukov <dvyukov@google.com>
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Date: Mon, 15 Jan 2018 13:01:07 +0100
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On Mon, 2018-01-15 at 10:12 +0100, Dmitry Vyukov wrote:

> However, there can be some surprising things, for example, executing
> one ioctl/setsockopt with data meant for another one, or these
> 0xffffffffffffffff are actually mean 0 (for involved reasons), 

I think those fff was actually what was throwing me off.

> or we
> can simply have bugs in these descriptions so they don't match C
> structures and then all data is messed/shifted.

No, I think this part was OK.

> If this representation does not make sense to you right away, your
> best bet is looking at/running the C reproducer where you can see true
> data layout:
> 
> 
[...]
Yeah, good point, I should've just done that.

> > Ah, then again, now I see the fault injection - I guess dev_set_name()
> > just failed and we didn't check the return value, will fix that.
> 
> Yes, it's highly likely the root cause. The raw.log file shows there
> there was an immediately preceding fault in kmalloc in the same
> process, in a close stack.

Yep, I submitted the fix now (with the correct reported-by).

Also for the other one, the wiphy_register() warning.

johannes