Remove execution domain support

All users of exec_domain are gone, now we can get rid
of that abandoned feature.
To not break existing userspace we keep a dummy
/proc/execdomains file which will always contain
"0-0     Linux                   [kernel]".

Signed-off-by: Richard Weinberger <richard@nod.at>
This commit is contained in:
Richard Weinberger 2015-03-30 08:14:16 +02:00
parent 3c7a49d074
commit 973f911f55
3 changed files with 1 additions and 105 deletions

View File

@ -20,13 +20,7 @@
#include <linux/types.h>
#include <linux/fs_struct.h>
static void default_handler(int, struct pt_regs *);
static struct exec_domain *exec_domains = &default_exec_domain;
static DEFINE_RWLOCK(exec_domains_lock);
static unsigned long ident_map[32] = {
0, 1, 2, 3, 4, 5, 6, 7,
8, 9, 10, 11, 12, 13, 14, 15,
@ -55,94 +49,9 @@ default_handler(int segment, struct pt_regs *regp)
send_sig(SIGSEGV, current, 1);
}
static struct exec_domain *
lookup_exec_domain(unsigned int personality)
{
unsigned int pers = personality(personality);
struct exec_domain *ep;
read_lock(&exec_domains_lock);
for (ep = exec_domains; ep; ep = ep->next) {
if (pers >= ep->pers_low && pers <= ep->pers_high)
if (try_module_get(ep->module))
goto out;
}
#ifdef CONFIG_MODULES
read_unlock(&exec_domains_lock);
request_module("personality-%d", pers);
read_lock(&exec_domains_lock);
for (ep = exec_domains; ep; ep = ep->next) {
if (pers >= ep->pers_low && pers <= ep->pers_high)
if (try_module_get(ep->module))
goto out;
}
#endif
ep = &default_exec_domain;
out:
read_unlock(&exec_domains_lock);
return ep;
}
int
register_exec_domain(struct exec_domain *ep)
{
struct exec_domain *tmp;
int err = -EBUSY;
if (ep == NULL)
return -EINVAL;
if (ep->next != NULL)
return -EBUSY;
write_lock(&exec_domains_lock);
for (tmp = exec_domains; tmp; tmp = tmp->next) {
if (tmp == ep)
goto out;
}
ep->next = exec_domains;
exec_domains = ep;
err = 0;
out:
write_unlock(&exec_domains_lock);
return err;
}
EXPORT_SYMBOL(register_exec_domain);
int
unregister_exec_domain(struct exec_domain *ep)
{
struct exec_domain **epp;
epp = &exec_domains;
write_lock(&exec_domains_lock);
for (epp = &exec_domains; *epp; epp = &(*epp)->next) {
if (ep == *epp)
goto unregister;
}
write_unlock(&exec_domains_lock);
return -EINVAL;
unregister:
*epp = ep->next;
ep->next = NULL;
write_unlock(&exec_domains_lock);
return 0;
}
EXPORT_SYMBOL(unregister_exec_domain);
int __set_personality(unsigned int personality)
{
struct exec_domain *oep = current_thread_info()->exec_domain;
current_thread_info()->exec_domain = lookup_exec_domain(personality);
current->personality = personality;
module_put(oep->module);
return 0;
}
@ -151,14 +60,7 @@ EXPORT_SYMBOL(__set_personality);
#ifdef CONFIG_PROC_FS
static int execdomains_proc_show(struct seq_file *m, void *v)
{
struct exec_domain *ep;
read_lock(&exec_domains_lock);
for (ep = exec_domains; ep; ep = ep->next)
seq_printf(m, "%d-%d\t%-16s\t[%s]\n",
ep->pers_low, ep->pers_high, ep->name,
module_name(ep->module));
read_unlock(&exec_domains_lock);
seq_puts(m, "0-0\tLinux \t[kernel]\n");
return 0;
}

View File

@ -756,8 +756,6 @@ void do_exit(long code)
cgroup_exit(tsk);
module_put(task_thread_info(tsk)->exec_domain->module);
/*
* FIXME: do that only when needed, using sched_exit tracepoint
*/

View File

@ -1279,9 +1279,6 @@ static struct task_struct *copy_process(unsigned long clone_flags,
if (nr_threads >= max_threads)
goto bad_fork_cleanup_count;
if (!try_module_get(task_thread_info(p)->exec_domain->module))
goto bad_fork_cleanup_count;
delayacct_tsk_init(p); /* Must remain after dup_task_struct() */
p->flags &= ~(PF_SUPERPRIV | PF_WQ_WORKER);
p->flags |= PF_FORKNOEXEC;
@ -1590,7 +1587,6 @@ bad_fork_cleanup_threadgroup_lock:
if (clone_flags & CLONE_THREAD)
threadgroup_change_end(current);
delayacct_tsk_free(p);
module_put(task_thread_info(p)->exec_domain->module);
bad_fork_cleanup_count:
atomic_dec(&p->cred->user->processes);
exit_creds(p);