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ata: pata_parport: fix memory leaks

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When ida_alloc() fails, "pi" is not freed although the misleading
comment says otherwise.
Move the ida_alloc() call up so we really don't have to free "pi" in
case of ida_alloc() failure.

Also move ida_free() call from pi_remove_one() to
pata_parport_dev_release(). It was dereferencing already freed dev
pointer.

Testing revealed leak even in non-failure case which was tracked down
to missing put_device() call after bus_find_device_by_name(). As a
result, pata_parport_dev_release() was never called.

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Link: https://lore.kernel.org/r/202303111822.IHNchbkp-lkp@intel.com/
Signed-off-by: Ondrej Zary <linux@zary.sk>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
This commit is contained in:
Ondrej Zary 2023-03-14 23:58:05 +01:00 committed by Damien Le Moal
parent dc472c7612
commit 5bc9e2d43f
1 changed files with 15 additions and 12 deletions
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27
drivers/ata/pata_parport/pata_parport.c
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@ -381,6 +381,7 @@ static void pata_parport_dev_release(struct device *dev)
{ {
struct pi_adapter *pi = container_of(dev, struct pi_adapter, dev); struct pi_adapter *pi = container_of(dev, struct pi_adapter, dev);
ida_free(&pata_parport_bus_dev_ids, dev->id);
kfree(pi); kfree(pi);
} }
@ -433,23 +434,27 @@ static struct pi_adapter *pi_init_one(struct parport *parport,
if (bus_for_each_dev(&pata_parport_bus_type, NULL, &match, pi_find_dev)) if (bus_for_each_dev(&pata_parport_bus_type, NULL, &match, pi_find_dev))
return NULL; return NULL;
pi = kzalloc(sizeof(struct pi_adapter), GFP_KERNEL); id = ida_alloc(&pata_parport_bus_dev_ids, GFP_KERNEL);
if (!pi) if (id < 0)
return NULL; return NULL;
pi = kzalloc(sizeof(struct pi_adapter), GFP_KERNEL);
if (!pi) {
ida_free(&pata_parport_bus_dev_ids, id);
return NULL;
}
/* set up pi->dev before pi_probe_unit() so it can use dev_printk() */ /* set up pi->dev before pi_probe_unit() so it can use dev_printk() */
pi->dev.parent = &pata_parport_bus; pi->dev.parent = &pata_parport_bus;
pi->dev.bus = &pata_parport_bus_type; pi->dev.bus = &pata_parport_bus_type;
pi->dev.driver = &pr->driver; pi->dev.driver = &pr->driver;
pi->dev.release = pata_parport_dev_release; pi->dev.release = pata_parport_dev_release;
id = ida_alloc(&pata_parport_bus_dev_ids, GFP_KERNEL);
if (id < 0)
return NULL; /* pata_parport_dev_release will do kfree(pi) */
pi->dev.id = id; pi->dev.id = id;
dev_set_name(&pi->dev, "pata_parport.%u", pi->dev.id); dev_set_name(&pi->dev, "pata_parport.%u", pi->dev.id);
if (device_register(&pi->dev)) { if (device_register(&pi->dev)) {
put_device(&pi->dev); put_device(&pi->dev);
goto out_ida_free; /* pata_parport_dev_release will do ida_free(dev->id) and kfree(pi) */
return NULL;
} }
pi->proto = pr; pi->proto = pr;
@ -464,8 +469,7 @@ static struct pi_adapter *pi_init_one(struct parport *parport,
pi->port = parport->base; pi->port = parport->base;
par_cb.private = pi; par_cb.private = pi;
pi->pardev = parport_register_dev_model(parport, DRV_NAME, &par_cb, pi->pardev = parport_register_dev_model(parport, DRV_NAME, &par_cb, id);
pi->dev.id);
if (!pi->pardev) if (!pi->pardev)
goto out_module_put; goto out_module_put;
@ -501,8 +505,7 @@ out_module_put:
module_put(pi->proto->owner); module_put(pi->proto->owner);
out_unreg_dev: out_unreg_dev:
device_unregister(&pi->dev); device_unregister(&pi->dev);
out_ida_free: /* pata_parport_dev_release will do ida_free(dev->id) and kfree(pi) */
ida_free(&pata_parport_bus_dev_ids, pi->dev.id);
return NULL; return NULL;
} }
@ -627,8 +630,7 @@ static void pi_remove_one(struct device *dev)
pi_disconnect(pi); pi_disconnect(pi);
pi_release(pi); pi_release(pi);
device_unregister(dev); device_unregister(dev);
ida_free(&pata_parport_bus_dev_ids, dev->id); /* pata_parport_dev_release will do ida_free(dev->id) and kfree(pi) */
/* pata_parport_dev_release will do kfree(pi) */
} }
static ssize_t delete_device_store(struct bus_type *bus, const char *buf, static ssize_t delete_device_store(struct bus_type *bus, const char *buf,
@ -644,6 +646,7 @@ static ssize_t delete_device_store(struct bus_type *bus, const char *buf,
} }
pi_remove_one(dev); pi_remove_one(dev);
put_device(dev);
mutex_unlock(&pi_mutex); mutex_unlock(&pi_mutex);
return count; return count;