[SLOF] [PATCH 8/9] libc: Check for NULL pointers in free()

[Greg Kurz]

On Thu, 17 May 2018 19:40:55 +0200
Thomas Huth <thuth at redhat.com> wrote:

> POSIX says that the free() function should simply do nothing if a NULL
> pointer argument has been specified. So let's be a little bit more
> compliant in our libc and add a NULL pointer check here, too.
> 
> Signed-off-by: Thomas Huth <thuth at redhat.com>
> ---

Reviewed-by: Greg Kurz <groug at kaod.org>

>  lib/libc/stdlib/free.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/lib/libc/stdlib/free.c b/lib/libc/stdlib/free.c
> index 9005450..d276585 100644
> --- a/lib/libc/stdlib/free.c
> +++ b/lib/libc/stdlib/free.c
> @@ -19,8 +19,10 @@ free(void *ptr)
>  {
>  	struct chunk *header;
>  
> +	if (!ptr)
> +		return;
> +
>  	header = (struct chunk *) ptr;
>  	header--;
>  	header->inuse = 0;
> -
>  }