Re: [PATCH] kdb: fix strncpy warning

From: Olof Johansson
Date: Sat Nov 03 2018 - 12:55:10 EST


On Sat, Nov 3, 2018 at 8:39 AM Daniel Thompson
<daniel.thompson@xxxxxxxxxx> wrote:
>
> On Fri, Nov 02, 2018 at 02:24:05PM -0700, Olof Johansson wrote:
> > kdb does a strncpy(a, b, strlen(b)+1), which makes no sense. Might as
> > well do a strcpy at this point.
> >
> > Fixes this warning:
> >
> > In function 'strncpy', inlined from 'kallsyms_symbol_next' at kernel/debug/kdb/kdb_support.c:239:4:
> > ./include/linux/string.h:253:9: warning: '__builtin_strncpy' specified bound depends on the length of the source argument [-Wstringop-overflow=]
>
> I think we already have a pending patch for this:
> https://lore.kernel.org/patchwork/patch/989013/
>
> When we looked into this there actually is an unchecked overflow here so
> Prarit's fix adds infrastructure to keep track of the remaining length.

I'm not surprised that there are more bugs.

The above patch was posted a month and a half ago though, why is it
not yet merged? Can we get it in by -rc2, please?


-Olof