Return-path: Received: from mail-pd0-f182.google.com ([209.85.192.182]:64442 "EHLO mail-pd0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752559AbaJ1Bce (ORCPT ); Mon, 27 Oct 2014 21:32:34 -0400 From: Junjie Mao To: Martin Pitt Cc: Junjie Mao , Fengguang Wu , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] mac80211_hwsim: release driver when ieee80211_register_hw fails Date: Tue, 28 Oct 2014 09:31:47 +0800 Message-Id: <1414459907-7509-1-git-send-email-eternal.n08@gmail.com> (sfid-20141028_023301_948024_70359C07) Sender: linux-wireless-owner@vger.kernel.org List-ID: The driver is not released when ieee80211_register_hw fails in mac80211_hwsim_create_radio, leading to the access to the unregistered (and possibly freed) device in platform_driver_unregister: [ 0.447547] mac80211_hwsim: ieee80211_register_hw failed (-2) [ 0.448292] ------------[ cut here ]------------ [ 0.448854] WARNING: CPU: 0 PID: 1 at ../include/linux/kref.h:47 kobject_get+0x33/0x50() [ 0.449839] CPU: 0 PID: 1 Comm: swapper Not tainted 3.17.0-00001-gdd46990-dirty #2 [ 0.450813] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 0.451512] 00000000 00000000 78025e38 7967c6c6 78025e68 7905e09b 7988b480 00000000 [ 0.452579] 00000001 79887d62 0000002f 79170bb3 79170bb3 78397008 79ac9d74 00000001 [ 0.453614] 78025e78 7905e15d 00000009 00000000 78025e84 79170bb3 78397000 78025e8c [ 0.454632] Call Trace: [ 0.454921] [<7967c6c6>] dump_stack+0x16/0x18 [ 0.455453] [<7905e09b>] warn_slowpath_common+0x6b/0x90 [ 0.456067] [<79170bb3>] ? kobject_get+0x33/0x50 [ 0.456612] [<79170bb3>] ? kobject_get+0x33/0x50 [ 0.457155] [<7905e15d>] warn_slowpath_null+0x1d/0x20 [ 0.457748] [<79170bb3>] kobject_get+0x33/0x50 [ 0.458274] [<7925824f>] get_device+0xf/0x20 [ 0.458779] [<7925b5cd>] driver_detach+0x3d/0xa0 [ 0.459331] [<7925a3ff>] bus_remove_driver+0x8f/0xb0 [ 0.459927] [<7925bf80>] ? class_unregister+0x40/0x80 [ 0.460660] [<7925bad7>] driver_unregister+0x47/0x50 [ 0.461248] [<7925c033>] ? class_destroy+0x13/0x20 [ 0.461824] [<7925d07b>] platform_driver_unregister+0xb/0x10 [ 0.462507] [<79b51ba0>] init_mac80211_hwsim+0x3e8/0x3f9 [ 0.463161] [<79b30c58>] do_one_initcall+0x106/0x1a9 [ 0.463758] [<79b517b8>] ? if_spi_init_module+0xac/0xac [ 0.464393] [<79b517b8>] ? if_spi_init_module+0xac/0xac [ 0.465001] [<79071935>] ? parse_args+0x2f5/0x480 [ 0.465569] [<7906b41e>] ? __usermodehelper_set_disable_depth+0x3e/0x50 [ 0.466345] [<79b30dd9>] kernel_init_freeable+0xde/0x17d [ 0.466972] [<79b304d6>] ? do_early_param+0x7a/0x7a [ 0.467546] [<79677b1b>] kernel_init+0xb/0xe0 [ 0.468072] [<79075f42>] ? schedule_tail+0x12/0x40 [ 0.468658] [<79686580>] ret_from_kernel_thread+0x20/0x30 [ 0.469303] [<79677b10>] ? rest_init+0xc0/0xc0 [ 0.469829] ---[ end trace ad8ac403ff8aef5c ]--- [ 0.470509] ------------[ cut here ]------------ [ 0.471047] WARNING: CPU: 0 PID: 1 at ../kernel/locking/lockdep.c:3161 __lock_acquire.isra.22+0x7aa/0xb00() [ 0.472163] DEBUG_LOCKS_WARN_ON(id >= MAX_LOCKDEP_KEYS) [ 0.472774] CPU: 0 PID: 1 Comm: swapper Tainted: G W 3.17.0-00001-gdd46990-dirty #2 [ 0.473815] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 0.474492] 78025de0 78025de0 78025da0 7967c6c6 78025dd0 7905e09b 79888931 78025dfc [ 0.475515] 00000001 79888a93 00000c59 7907f33a 7907f33a 78028000 fffe9d09 00000000 [ 0.476519] 78025de8 7905e10e 00000009 78025de0 79888931 78025dfc 78025e24 7907f33a [ 0.477523] Call Trace: [ 0.477821] [<7967c6c6>] dump_stack+0x16/0x18 [ 0.478352] [<7905e09b>] warn_slowpath_common+0x6b/0x90 [ 0.478976] [<7907f33a>] ? __lock_acquire.isra.22+0x7aa/0xb00 [ 0.479658] [<7907f33a>] ? __lock_acquire.isra.22+0x7aa/0xb00 [ 0.480417] [<7905e10e>] warn_slowpath_fmt+0x2e/0x30 [ 0.480479] [<7907f33a>] __lock_acquire.isra.22+0x7aa/0xb00 [ 0.480479] [<79078aa5>] ? sched_clock_cpu+0xb5/0xf0 [ 0.480479] [<7907fd06>] lock_acquire+0x56/0x70 [ 0.480479] [<7925b5e8>] ? driver_detach+0x58/0xa0 [ 0.480479] [<79682d11>] mutex_lock_nested+0x61/0x2a0 [ 0.480479] [<7925b5e8>] ? driver_detach+0x58/0xa0 [ 0.480479] [<7925b5e8>] ? driver_detach+0x58/0xa0 [ 0.480479] [<7925b5e8>] driver_detach+0x58/0xa0 [ 0.480479] [<7925a3ff>] bus_remove_driver+0x8f/0xb0 [ 0.480479] [<7925bf80>] ? class_unregister+0x40/0x80 [ 0.480479] [<7925bad7>] driver_unregister+0x47/0x50 [ 0.480479] [<7925c033>] ? class_destroy+0x13/0x20 [ 0.480479] [<7925d07b>] platform_driver_unregister+0xb/0x10 [ 0.480479] [<79b51ba0>] init_mac80211_hwsim+0x3e8/0x3f9 [ 0.480479] [<79b30c58>] do_one_initcall+0x106/0x1a9 [ 0.480479] [<79b517b8>] ? if_spi_init_module+0xac/0xac [ 0.480479] [<79b517b8>] ? if_spi_init_module+0xac/0xac [ 0.480479] [<79071935>] ? parse_args+0x2f5/0x480 [ 0.480479] [<7906b41e>] ? __usermodehelper_set_disable_depth+0x3e/0x50 [ 0.480479] [<79b30dd9>] kernel_init_freeable+0xde/0x17d [ 0.480479] [<79b304d6>] ? do_early_param+0x7a/0x7a [ 0.480479] [<79677b1b>] kernel_init+0xb/0xe0 [ 0.480479] [<79075f42>] ? schedule_tail+0x12/0x40 [ 0.480479] [<79686580>] ret_from_kernel_thread+0x20/0x30 [ 0.480479] [<79677b10>] ? rest_init+0xc0/0xc0 [ 0.480479] ---[ end trace ad8ac403ff8aef5d ]--- [ 0.495478] BUG: unable to handle kernel paging request at 00200200 [ 0.496257] IP: [<79682de5>] mutex_lock_nested+0x135/0x2a0 [ 0.496923] *pde = 00000000 [ 0.497290] Oops: 0002 [#1] [ 0.497653] CPU: 0 PID: 1 Comm: swapper Tainted: G W 3.17.0-00001-gdd46990-dirty #2 [ 0.498659] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 0.499321] task: 78028000 ti: 78024000 task.ti: 78024000 [ 0.499955] EIP: 0060:[<79682de5>] EFLAGS: 00010097 CPU: 0 [ 0.500620] EIP is at mutex_lock_nested+0x135/0x2a0 [ 0.501145] EAX: 00200200 EBX: 78397434 ECX: 78397460 EDX: 78025e70 [ 0.501816] ESI: 00000246 EDI: 78028000 EBP: 78025e8c ESP: 78025e54 [ 0.502497] DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068 [ 0.503076] CR0: 8005003b CR2: 00200200 CR3: 01b9d000 CR4: 00000690 [ 0.503773] Stack: [ 0.503998] 00000000 00000001 00000000 7925b5e8 78397460 7925b5e8 78397474 78397460 [ 0.504944] 00200200 11111111 78025e70 78397000 79ac9d74 00000001 78025ea0 7925b5e8 [ 0.505451] 79ac9d74 fffffffe 00000001 78025ebc 7925a3ff 7a251398 78025ec8 7925bf80 [ 0.505451] Call Trace: [ 0.505451] [<7925b5e8>] ? driver_detach+0x58/0xa0 [ 0.505451] [<7925b5e8>] ? driver_detach+0x58/0xa0 [ 0.505451] [<7925b5e8>] driver_detach+0x58/0xa0 [ 0.505451] [<7925a3ff>] bus_remove_driver+0x8f/0xb0 [ 0.505451] [<7925bf80>] ? class_unregister+0x40/0x80 [ 0.505451] [<7925bad7>] driver_unregister+0x47/0x50 [ 0.505451] [<7925c033>] ? class_destroy+0x13/0x20 [ 0.505451] [<7925d07b>] platform_driver_unregister+0xb/0x10 [ 0.505451] [<79b51ba0>] init_mac80211_hwsim+0x3e8/0x3f9 [ 0.505451] [<79b30c58>] do_one_initcall+0x106/0x1a9 [ 0.505451] [<79b517b8>] ? if_spi_init_module+0xac/0xac [ 0.505451] [<79b517b8>] ? if_spi_init_module+0xac/0xac [ 0.505451] [<79071935>] ? parse_args+0x2f5/0x480 [ 0.505451] [<7906b41e>] ? __usermodehelper_set_disable_depth+0x3e/0x50 [ 0.505451] [<79b30dd9>] kernel_init_freeable+0xde/0x17d [ 0.505451] [<79b304d6>] ? do_early_param+0x7a/0x7a [ 0.505451] [<79677b1b>] kernel_init+0xb/0xe0 [ 0.505451] [<79075f42>] ? schedule_tail+0x12/0x40 [ 0.505451] [<79686580>] ret_from_kernel_thread+0x20/0x30 [ 0.505451] [<79677b10>] ? rest_init+0xc0/0xc0 [ 0.505451] Code: 89 d8 e8 cf 9b 9f ff 8b 4f 04 8d 55 e4 89 d8 e8 72 9d 9f ff 8d 43 2c 89 c1 89 45 d8 8b 43 30 8d 55 e4 89 53 30 89 4d e4 89 45 e8 <89> 10 8b 55 dc 8b 45 e0 89 7d ec e8 db af 9f ff eb 11 90 31 c0 [ 0.505451] EIP: [<79682de5>] mutex_lock_nested+0x135/0x2a0 SS:ESP 0068:78025e54 [ 0.505451] CR2: 0000000000200200 [ 0.505451] ---[ end trace ad8ac403ff8aef5e ]--- [ 0.505451] Kernel panic - not syncing: Fatal exception Fixes: 9ea927748ced ("mac80211_hwsim: Register and bind to driver") Reported-by: Fengguang Wu Signed-off-by: Junjie Mao --- drivers/net/wireless/mac80211_hwsim.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/mac80211_hwsim.c b/drivers/net/wireless/mac80211_hwsim.c index babbdc1ce741..c9ad4cf1adfb 100644 --- a/drivers/net/wireless/mac80211_hwsim.c +++ b/drivers/net/wireless/mac80211_hwsim.c @@ -1987,7 +1987,7 @@ static int mac80211_hwsim_create_radio(int channels, const char *reg_alpha2, if (err != 0) { printk(KERN_DEBUG "mac80211_hwsim: device_bind_driver failed (%d)\n", err); - goto failed_hw; + goto failed_bind; } skb_queue_head_init(&data->pending); @@ -2183,6 +2183,8 @@ static int mac80211_hwsim_create_radio(int channels, const char *reg_alpha2, return idx; failed_hw: + device_release_driver(data->dev); +failed_bind: device_unregister(data->dev); failed_drvdata: ieee80211_free_hw(hw); -- 1.9.3