Messages in this thread | | | Date | Tue, 15 Apr 2014 14:18:00 +0300 | From | Dan Carpenter <> | Subject | Re: + lib-stringc-strlcpy-might-read-too-far.patch added to -mm tree |
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On Tue, Apr 15, 2014 at 01:49:38PM +0300, Alexey Dobriyan wrote: > Return value matters. It may not matter for kernel, because kernel is > not heavy string user. > But it is better to not diverge from master code: > http://www.openbsd.org/cgi-bin/cvsweb/src/lib/libc/string/strlcpy.c?rev=1.11 >
Oh... Hm. Maybe we should drop this patch then.
> Counter-rationale: > * strlcpy() accepts strings, so if you're giving raw buffer you're > doing it wrong. > * last byte of last page argument is bogus because kernel copies data > from userspace first.
The last byte of the page argument seems possible:
foo = kmalloc(); copy_from_user(foo, arg, sizeof(foo)); strlcpy(dest.str, foo->bar, sizeof(dest.str));
It's a very unlikely scenario. You have to be very unlucky to hit it at all.
regards, dan carpenter
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