From: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx> [ Upstream commit 448a496f760664d3e2e79466aa1787e6abc922b5 ] device_add shall not be called multiple times as stated in its documentation: 'Do not call this routine or device_register() more than once for any device structure' Syzkaller reports a bug as follows [1]: ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:33! invalid opcode: 0000 [#1] PREEMPT SMP KASAN [...] Call Trace: <TASK> __list_add include/linux/list.h:69 [inline] list_add_tail include/linux/list.h:102 [inline] kobj_kset_join lib/kobject.c:164 [inline] kobject_add_internal+0x18f/0x8f0 lib/kobject.c:214 kobject_add_varg lib/kobject.c:358 [inline] kobject_add+0x150/0x1c0 lib/kobject.c:410 device_add+0x368/0x1e90 drivers/base/core.c:3452 hci_conn_add_sysfs+0x9b/0x1b0 net/bluetooth/hci_sysfs.c:53 hci_le_cis_estabilished_evt+0x57c/0xae0 net/bluetooth/hci_event.c:6799 hci_le_meta_evt+0x2b8/0x510 net/bluetooth/hci_event.c:7110 hci_event_func net/bluetooth/hci_event.c:7440 [inline] hci_event_packet+0x63d/0xfd0 net/bluetooth/hci_event.c:7495 hci_rx_work+0xae7/0x1230 net/bluetooth/hci_core.c:4007 process_one_work+0x991/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 </TASK> Link: https://syzkaller.appspot.com/bug?id=da3246e2d33afdb92d66bc166a0934c5b146404a Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx> Tested-by: Hawkins Jiawei <yin31149@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/bluetooth/hci_sysfs.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/bluetooth/hci_sysfs.c b/net/bluetooth/hci_sysfs.c index 4e3e0451b08c..08542dfc2dc5 100644 --- a/net/bluetooth/hci_sysfs.c +++ b/net/bluetooth/hci_sysfs.c @@ -48,6 +48,9 @@ void hci_conn_add_sysfs(struct hci_conn *conn) BT_DBG("conn %p", conn); + if (device_is_registered(&conn->dev)) + return; + dev_set_name(&conn->dev, "%s:%d", hdev->name, conn->handle); if (device_add(&conn->dev) < 0) { -- 2.35.1
