Re: Fw: Re: oops in choose_configuration()

[Linus Torvalds <torvalds@osdl.org>]

On Tue, 7 Mar 2006, Chuck Ebbert wrote:
> 
> At least one susbsystem rolls its own method of adding env vars to the
> uevent buffer, and it's so broken it triggers the WARN_ON() in
> lib/vsprintf.c::vsnprintf() by passing a negative length to that function.

Well, snprintf() should be safe, though. It will warn if the caller is 
lazy, but these days, the thing does

	max(buf_size - len, 0)

which should mean that the input layer passes in 0 instead of a negative 
number. And snprintf() will then _not_ print anything. 

So I think input_add_uevent_bm_var() is safe, even if it's not pretty.

However, input_devices_read() doesn't do any sanity checking at all, and 
if that ever ends up printing more than a page, that would be bad. I 
didn't look very closely, but it looks worrisome.

Dmitry?

		Linus
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