bug#19784: build fails on make-prime-list when asan is enabled

[Yury Usishchev]

On 02/05/2015 09:06 PM, Pádraig Brady wrote:
> On 05/02/15 15:21, Yury Usishchev wrote:
> > Hello!
> >
> > We tried to build coreutils with address sanitizer enabled and
> > encountered an error:
> >
> >     GEN      src/primes.h
> > ==12657== ERROR: AddressSanitizer: heap-buffer-overflow
> >
> > This can be reproduced on git master using gcc-4.8 or gcc-4.9 by
> > git clone
> > export CFLAGS="-fsanitize=address"
> > ./bootstrap
> > ./configure
> > make
> >
> > and is caused by line
> > src/make-prime-list.c:214:      while (i < size && sieve[++i] == 0)
> >
> > When 'i' reaches 'size-1' it gets incremented and then
> > (unallocated)memory is accessed.
> >
> > I attached patch that can fix this issue.
> Oh nice one. That was not rerun when I ran my checks.
> The released tools (still) pass with -fsanitize=address.
>
> How about this fix instead?  I'll push in your name if
> you're ok with it.
>
> diff --git a/src/make-prime-list.c b/src/make-prime-list.c
> index 68c972a..69b91e8 100644
> --- a/src/make-prime-list.c
> +++ b/src/make-prime-list.c
> @@ -211,7 +211,7 @@ main (int argc, char **argv)
>         for (j = (p*p - 3)/2; j < size; j+= p)
>           sieve[j] = 0;
>
> -      while (i < size && sieve[++i] == 0)
> +      while (++i < size && sieve[i] == 0)
>           ;
>       }
Thank you for quick reply.
Yes, this patch looks much better.

--
BR,
Yury Usishchev