[PATCH -next] scsi: bsg: Fix memory leak in bsg_register_queue()

[PATCH -next] scsi: bsg: Fix memory leak in bsg_register_queue()

[Bixuan Cui]

Kmemleak tool detected a memory leak.

BUG: memory leak
unreferenced object 0xffff8881170da100 (size 32):
  comm "kworker/u4:4", pid 2996, jiffies 4294948956 (age 24.640s)
  hex dump (first 32 bytes):
    38 3a 30 3a 30 3a 31 00 00 00 00 00 00 00 00 00  8:0:0:1.........
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<ffffffff8147fc76>] kstrdup+0x36/0x70 mm/util.c:60
    [<ffffffff8147fd03>] kstrdup_const+0x53/0x80 mm/util.c:83
    [<ffffffff82293362>] kvasprintf_const+0xc2/0x110 lib/kasprintf.c:48
    [<ffffffff8235545b>] kobject_set_name_vargs+0x3b/0xe0 lib/kobject.c:289
    [<ffffffff82652573>] dev_set_name+0x63/0x90 drivers/base/core.c:3147
    [<ffffffff822547d1>] bsg_register_queue+0xe1/0x1d0 block/bsg.c:201
    [<ffffffff82730abf>] scsi_sysfs_add_sdev+0x13f/0x380 drivers/scsi/scsi_sysfs.c:1376
    [<ffffffff8272e309>] scsi_sysfs_add_devices drivers/scsi/scsi_scan.c:1727 [inline]
    [<ffffffff8272e309>] scsi_finish_async_scan drivers/scsi/scsi_scan.c:1812 [inline]
    [<ffffffff8272e309>] do_scan_async+0x109/0x200 drivers/scsi/scsi_scan.c:1855
    [<ffffffff812752a4>] async_run_entry_fn+0x24/0xf0 kernel/async.c:127
    [<ffffffff81263d1f>] process_one_work+0x2cf/0x620 kernel/workqueue.c:2297
    [<ffffffff81264629>] worker_thread+0x59/0x5d0 kernel/workqueue.c:2444
    [<ffffffff8126db28>] kthread+0x188/0x1d0 kernel/kthread.c:319
    [<ffffffff8100234f>] ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

The bsg_register_queue() use device_initialize() and dev_set_name() to
registe device. That way if it fails, call put_device() to clean up
correctly.

Reported-by: syzbot+cfe9b7cf55bb54ed4e57@syzkaller.appspotmail.com
Signed-off-by: Bixuan Cui <cuibixuan@huawei.com>
---
 block/bsg.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/block/bsg.c b/block/bsg.c
index 351095193788..4d6803dad0b3 100644
--- a/block/bsg.c
+++ b/block/bsg.c
@@ -219,6 +219,7 @@ struct bsg_device *bsg_register_queue(struct request_queue *q,
 	cdev_device_del(&bd->cdev, &bd->device);
 out_ida_remove:
 	ida_simple_remove(&bsg_minor_ida, MINOR(bd->device.devt));
+	put_device(&bd->device);
 out_kfree:
 	kfree(bd);
 	return ERR_PTR(ret);
-- 
2.17.1