staging: speakup: more fixes for init-failure handling.

We still leaked many resources when Speakup failed to initialize.
Examples of leaked resources include:
/dev/synth, keyboard or VT notifiers, and heap-allocated st_spk_t
structs.
This is fixed.

* We now use PTR_ERR to detect kthread_create failure
(thank you Dan Carpenter).

* The loop which frees members of the speakup_console array now iterates
over the whole array, not stopping at the first NULL value.  Fixes
a possible memory leak.  Safe because kfree(NULL) is a no-op.

* The order of some initializations was changed.  The safe ones, which
will never fail, are performed first.

Signed-off-by: Christopher Brannon <chris@the-brannons.com>
Acked-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Christopher Brannon 2010-12-19 22:50:24 +00:00 committed by Greg Kroah-Hartman
parent 0bbfc0edb7
commit 628f34282d

View File

@ -1283,7 +1283,7 @@ static int edit_bits(struct vc_data *vc, u_char type, u_char ch, u_short key)
}
/* Allocation concurrency is protected by the console semaphore */
void speakup_allocate(struct vc_data *vc)
int speakup_allocate(struct vc_data *vc)
{
int vc_num;
@ -1292,10 +1292,12 @@ void speakup_allocate(struct vc_data *vc)
speakup_console[vc_num] = kzalloc(sizeof(*speakup_console[0]),
GFP_ATOMIC);
if (speakup_console[vc_num] == NULL)
return;
return -ENOMEM;
speakup_date(vc);
} else if (!spk_parked)
speakup_date(vc);
return 0;
}
void speakup_deallocate(struct vc_data *vc)
@ -2217,18 +2219,23 @@ static void __exit speakup_exit(void)
{
int i;
free_user_msgs();
unregister_keyboard_notifier(&keyboard_notifier_block);
unregister_vt_notifier(&vt_notifier_block);
speakup_unregister_devsynth();
del_timer(&cursor_timer);
kthread_stop(speakup_task);
speakup_task = NULL;
mutex_lock(&spk_mutex);
synth_release();
mutex_unlock(&spk_mutex);
speakup_kobj_exit();
for (i = 0; i < MAX_NR_CONSOLES; i++)
kfree(speakup_console[i]);
speakup_remove_virtual_keyboard();
for (i = 0; i < MAXVARS; i++)
speakup_unregister_var(i);
@ -2236,42 +2243,23 @@ static void __exit speakup_exit(void)
if (characters[i] != default_chars[i])
kfree(characters[i]);
}
for (i = 0; speakup_console[i]; i++)
kfree(speakup_console[i]);
speakup_kobj_exit();
speakup_remove_virtual_keyboard();
free_user_msgs();
}
/* call by: module_init() */
static int __init speakup_init(void)
{
int i;
int err;
long err = 0;
struct st_spk_t *first_console;
struct vc_data *vc = vc_cons[fg_console].d;
struct var_t *var;
err = speakup_add_virtual_keyboard();
if (err)
goto out;
/* These first few initializations cannot fail. */
initialize_msgs(); /* Initialize arrays for i18n. */
first_console = kzalloc(sizeof(*first_console), GFP_KERNEL);
if (!first_console) {
err = -ENOMEM;
goto err_cons;
}
err = speakup_kobj_init();
if (err)
goto err_kobject;
reset_default_chars();
reset_default_chartab();
speakup_console[vc->vc_num] = first_console;
speakup_date(vc);
pr_info("speakup %s: initialized\n", SPEAKUP_VERSION);
strlwr(synth_name);
spk_vars[0].u.n.high = vc->vc_cols;
for (var = spk_vars; var->var_id != MAXVARS; var++)
@ -2286,31 +2274,92 @@ static int __init speakup_init(void)
if (quiet_boot)
spk_shut_up |= 0x01;
for (i = 0; i < MAX_NR_CONSOLES; i++)
if (vc_cons[i].d)
speakup_allocate(vc_cons[i].d);
/* From here on out, initializations can fail. */
err = speakup_add_virtual_keyboard();
if (err)
goto error_virtkeyboard;
first_console = kzalloc(sizeof(*first_console), GFP_KERNEL);
if (!first_console) {
err = -ENOMEM;
goto error_alloc;
}
speakup_console[vc->vc_num] = first_console;
speakup_date(vc);
for (i = 0; i < MAX_NR_CONSOLES; i++)
if (vc_cons[i].d) {
err = speakup_allocate(vc_cons[i].d);
if (err)
goto error_kobjects;
}
err = speakup_kobj_init();
if (err)
goto error_kobjects;
pr_warn("synth name on entry is: %s\n", synth_name);
synth_init(synth_name);
speakup_register_devsynth();
/*
* register_devsynth might fail, but this error is not fatal.
* /dev/synth is an extra feature; the rest of Speakup
* will work fine without it.
*/
register_keyboard_notifier(&keyboard_notifier_block);
register_vt_notifier(&vt_notifier_block);
err = register_keyboard_notifier(&keyboard_notifier_block);
if (err)
goto error_kbdnotifier;
err = register_vt_notifier(&vt_notifier_block);
if (err)
goto error_vtnotifier;
speakup_task = kthread_create(speakup_thread, NULL, "speakup");
set_user_nice(speakup_task, 10);
if (IS_ERR(speakup_task)) {
err = -ENOMEM;
goto err_kobject;
err = PTR_ERR(speakup_task);
goto error_task;
}
set_user_nice(speakup_task, 10);
wake_up_process(speakup_task);
pr_info("speakup %s: initialized\n", SPEAKUP_VERSION);
pr_info("synth name on entry is: %s\n", synth_name);
goto out;
err_kobject:
speakup_kobj_exit();
kfree(first_console);
err_cons:
error_task:
unregister_vt_notifier(&vt_notifier_block);
error_vtnotifier:
unregister_keyboard_notifier(&keyboard_notifier_block);
del_timer(&cursor_timer);
error_kbdnotifier:
speakup_unregister_devsynth();
mutex_lock(&spk_mutex);
synth_release();
mutex_unlock(&spk_mutex);
speakup_kobj_exit();
error_kobjects:
for (i = 0; i < MAX_NR_CONSOLES; i++)
kfree(speakup_console[i]);
error_alloc:
speakup_remove_virtual_keyboard();
error_virtkeyboard:
for (i = 0; i < MAXVARS; i++)
speakup_unregister_var(i);
for (i = 0; i < 256; i++) {
if (characters[i] != default_chars[i])
kfree(characters[i]);
}
free_user_msgs();
out:
return err;
}