From 5bc9e2d43f86105a95f86fa096fb4e517bb0ce73 Mon Sep 17 00:00:00 2001 From: Ondrej Zary Date: Tue, 14 Mar 2023 23:58:05 +0100 Subject: [PATCH] ata: pata_parport: fix memory leaks 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 Reported-by: Dan Carpenter Link: https://lore.kernel.org/r/202303111822.IHNchbkp-lkp@intel.com/ Signed-off-by: Ondrej Zary Signed-off-by: Damien Le Moal --- drivers/ata/pata_parport/pata_parport.c | 27 ++++++++++++++----------- 1 file changed, 15 insertions(+), 12 deletions(-) diff --git a/drivers/ata/pata_parport/pata_parport.c b/drivers/ata/pata_parport/pata_parport.c index 31c9677a45e3..c1576d943b43 100644 --- a/drivers/ata/pata_parport/pata_parport.c +++ b/drivers/ata/pata_parport/pata_parport.c @@ -381,6 +381,7 @@ static void pata_parport_dev_release(struct device *dev) { struct pi_adapter *pi = container_of(dev, struct pi_adapter, dev); + ida_free(&pata_parport_bus_dev_ids, dev->id); 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)) return NULL; - pi = kzalloc(sizeof(struct pi_adapter), GFP_KERNEL); - if (!pi) + id = ida_alloc(&pata_parport_bus_dev_ids, GFP_KERNEL); + if (id < 0) 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() */ pi->dev.parent = &pata_parport_bus; pi->dev.bus = &pata_parport_bus_type; pi->dev.driver = &pr->driver; 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; dev_set_name(&pi->dev, "pata_parport.%u", pi->dev.id); if (device_register(&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; @@ -464,8 +469,7 @@ static struct pi_adapter *pi_init_one(struct parport *parport, pi->port = parport->base; par_cb.private = pi; - pi->pardev = parport_register_dev_model(parport, DRV_NAME, &par_cb, - pi->dev.id); + pi->pardev = parport_register_dev_model(parport, DRV_NAME, &par_cb, id); if (!pi->pardev) goto out_module_put; @@ -501,8 +505,7 @@ out_module_put: module_put(pi->proto->owner); out_unreg_dev: device_unregister(&pi->dev); -out_ida_free: - ida_free(&pata_parport_bus_dev_ids, pi->dev.id); + /* pata_parport_dev_release will do ida_free(dev->id) and kfree(pi) */ return NULL; } @@ -627,8 +630,7 @@ static void pi_remove_one(struct device *dev) pi_disconnect(pi); pi_release(pi); device_unregister(dev); - ida_free(&pata_parport_bus_dev_ids, dev->id); - /* pata_parport_dev_release will do kfree(pi) */ + /* pata_parport_dev_release will do ida_free(dev->id) and kfree(pi) */ } 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); + put_device(dev); mutex_unlock(&pi_mutex); return count;