Hi, a quick review:
On Tue, Nov 26, 2024 at 10:43 AM Damien Zammit via Bug reports for the
GNU Hurd <bug-hurd@gnu.org> wrote:
> +static void
> +smp(char * const argv[])
Style nitpick: space before the paren.
> +{
> + int err;
error_t rather
> + unsigned int pset_count;
mach_msg_type_number_t rather (it's likely the same type, but still)
> + mach_port_t hostpriv;
> + processor_set_name_array_t psets = {0};
> + processor_set_t slave_pset = {0};
It's not an array in C sense, so if you want to zero-initialize it, =
MACH_PORT_NULL will do.
> + if (get_privileged_ports (&hostpriv, NULL))
> + error (1, 0, "Must be run as root for privileged cpu control");
err = get_privileged_ports (&hostpriv, NULL);
if (err)
error (1, err, "......");
> + err = host_processor_sets (hostpriv, &psets, &pset_count);
> + if (err)
> + error (1, 0, "Cannot get list of host processor sets");
error (1, err, "....")
> + if (pset_count < 2)
> + error (1, 0, "gnumach does not have the expected processor sets, are you
> running smp kernel?");
> +
> + err = host_processor_set_priv (hostpriv, psets[1], &slave_pset);
> + if (err)
> + error (1, 0, "Cannot get access to slave processor set");
same here
> +
> + err = task_assign(mach_task_self(), slave_pset, FALSE);
...spaces before the parens...
> + if (err)
> + error (1, 0, "Cannot assign task self to slave processor set");
err here too
> + /* Drop privileges from suid binary */
> + setuid(getuid());
*Before* you do that, it's very important that you deallocate the
ports you acquired above: hostpriv, all of psets, and slave_pset.
Moreover, you also have to deallocate _hurd_host_priv.
> + execve(argv[1], &argv[1], environ);
You should use execvp over execve here.
> + /* NOT REACHED */
It is reached if there was an error, e.g. the binary doesn't exist. So:
error (1, errno, "failed to execute %s", argv[1]);
Sergey
