[Intel-gfx] [PATCH] tests/gem_reset_stats: add close-pending-fork

[Chris Wilson]

On Mon, Dec 02, 2013 at 04:47:46PM +0200, Mika Kuoppala wrote:
> Fork and create another filedesc to wait access to already
> hung GPU and then kill it. This triggers use after free of the
> request->batch_obj.
> 
> Signed-off-by: Mika Kuoppala <mika.kuoppala at intel.com>
> ---
> +static int __test_open_any(void)
> +{
> +	char *name;
> +	int ret, fd;
> +
> +	ret = asprintf(&name, "/dev/dri/card%d", drm_get_card());
> +	if (ret == -1)
> +		return -1;
> +
> +	fd = open(name, O_RDWR);
> +	free(name);
> +
> +	return fd;
> +}
> +
> +static void test_close_pending_fork(void)
> +{
> +	int pid;
> +	int fd, fd2, h;
> +
> +	fd = drm_open_any();
> +	igt_assert(fd >= 0);

[snip]

> +	close(fd);
> +
> +	fd = drm_open_any();

This breaks the testsuite since drm_open_any() will now return the
closed fd. Hence your __test_open_any() above.

However this does not justify kernel doing anything other than terminating
your process with extreme prejudice.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre