Re: deprecated.rst: deprecated strcpy ? (was: [PATCH] checkpatch: add a new check for strcpy/strlcpy uses)

From: Kees Cook
Date: Fri Jan 08 2021 - 14:49:29 EST


On Thu, Jan 07, 2021 at 04:51:31PM -0800, Joe Perches wrote:
> I still like the stracpy variant I proposed:
>
> https://lore.kernel.org/lkml/24bb53c57767c1c2a8f266c305a670f7@xxxxxxx/T/#m0627aa770a076af1937cb5c610ed71dab3f1da72
> https://lore.kernel.org/lkml/CAHk-=wgqQKoAnhmhGE-2PBFt7oQs9LLAATKbYa573UO=DPBE0Q@xxxxxxxxxxxxxx/
>
> Linus liked a variant he called copy_string:
>
> https://lore.kernel.org/lkml/CAHk-=wg8vLmmwTGhXM51NpSWJW8RFEAKoXxG0Hu_Q9Uwbjj8kw@xxxxxxxxxxxxxx/
>
> I think the cocci scripts that convert:
>
> strlcpy -> strscpy (only when return value unused)
> str<sln>cpy(array, "string") -> stracpy(foo, "string")
> s[cn]printf -> sysfs_emit
>
> would leave relatively few uses of strcpy and sprintf variants and would
> make it much easier to analyze the remainder uses for potential overflows.

I think that would be lovely; yes. :)

--
Kees Cook