From f05faa31c387fb07f4c561350f00ba12cf673c9f Mon Sep 17 00:00:00 2001 From: Herton Ronaldo Krzesinski Date: Fri, 10 Apr 2009 18:05:14 -0300 Subject: [PATCH] rt2x00: prevent double kfree when failing to register hardware MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit In a scenario where there isn't any firmware available, we will have a double kfree of rt2x00dev->spec.channels_info when ieee80211_register_hw returns an error status inside rt2x00lib_probe_hw. The problem is that if ieee80211_register_hw fails, we call rt2x00lib_remove_hw twice: * first inside rt2x00lib_probe_hw upon failure of ieee80211_register_hw * error status is returned to rt2x00lib_probe_dev, which then sees it and calls in this case rt2x00lib_remove_dev that will again run rt2x00lib_remove_hw Prevent this avoiding calling rt2x00lib_remove_hw inside rt2x00lib_probe_hw Problem was detected with CONFIG_DEBUG_PAGEALLOC=y, CONFIG_SLUB_DEBUG=y, CONFIG_SLUB_DEBUG_ON=y, that dumps this with no firmware available: rt61pci 0000:00:07.0: PCI INT A -> GSI 19 (level, low) -> IRQ 19 wmaster0 (rt61pci): not using net_device_ops yet phy0: Selected rate control algorithm 'pid' phy0: Failed to initialize wep: -2 phy0 -> rt2x00lib_probe_dev: Error - Failed to initialize hw. ============================================================================= BUG kmalloc-128: Object already free ----------------------------------------------------------------------------- INFO: Allocated in rt61pci_probe_hw+0x3e5/0x6e0 [rt61pci] age=340 cpu=0 pid=21 INFO: Freed in rt2x00lib_remove_hw+0x59/0x70 [rt2x00lib] age=0 cpu=0 pid=21 INFO: Slab 0xc13ac3e0 objects=23 used=10 fp=0xdd59f6e0 flags=0x400000c3 INFO: Object 0xdd59f6e0 @offset=1760 fp=0xdd59f790 Bytes b4 0xdd59f6d0: 15 00 00 00 b2 8a fb ff 5a 5a 5a 5a 5a 5a 5a 5a ....².ûÿZZZZZZZZ Object 0xdd59f6e0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object 0xdd59f6f0: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object 0xdd59f700: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object 0xdd59f710: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object 0xdd59f720: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object 0xdd59f730: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object 0xdd59f740: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object 0xdd59f750: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b a5 kkkkkkkkkkkkkkk¥ Redzone 0xdd59f760: bb bb bb bb »»»» Padding 0xdd59f788: 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZ Pid: 21, comm: stage1 Not tainted 2.6.29.1-desktop-1.1mnb #1 Call Trace: [] print_trailer+0xd3/0x120 [] object_err+0x37/0x50 [] __slab_free+0xe7/0x2f0 [] kfree+0x7e/0xd0 [] ? rt2x00lib_remove_hw+0x59/0x70 [rt2x00lib] [] ? rt2x00lib_remove_hw+0x59/0x70 [rt2x00lib] [] rt2x00lib_remove_hw+0x59/0x70 [rt2x00lib] [] rt2x00lib_remove_dev+0x37/0x50 [rt2x00lib] [] rt2x00lib_probe_dev+0x1a7/0x3b0 [rt2x00lib] [] rt2x00pci_probe+0xdf/0x1ee [rt2x00pci] [] local_pci_probe+0xe/0x10 [] pci_device_probe+0x60/0x80 [] driver_probe_device+0x9a/0x2e0 [] __driver_attach+0x89/0x90 [] bus_for_each_dev+0x4b/0x70 [] ? pci_device_remove+0x0/0x40 [] driver_attach+0x19/0x20 [] ? __driver_attach+0x0/0x90 [] bus_add_driver+0x1cf/0x2a0 [] ? pci_device_remove+0x0/0x40 [] driver_register+0x69/0x140 [] __pci_register_driver+0x40/0x80 [] ? rt61pci_init+0x0/0x19 [rt61pci] [] rt61pci_init+0x17/0x19 [rt61pci] [] do_one_initcall+0x26/0x1c0 [] ? slab_pad_check+0x3c/0x120 [] ? slab_pad_check+0x3c/0x120 [] ? check_object+0xda/0x210 [] ? percpu_free+0x46/0x50 [] ? __slab_free+0x22e/0x2f0 [] ? percpu_free+0x46/0x50 [] ? percpu_free+0x46/0x50 [] ? percpu_free+0x46/0x50 [] ? stop_machine_destroy+0x3c/0x40 [] ? load_module+0xa5/0x1c50 [] ? rt61pci_eepromregister_read+0x0/0x40 [rt61pci] [] ? rt2x00pci_write_tx_data+0x0/0x90 [rt2x00pci] [] ? mutex_lock+0xb/0x20 [] ? mutex_lock+0xb/0x20 [] ? tracepoint_update_probe_range+0x76/0xa0 [] ? tracepoint_module_notify+0x2f/0x40 [] ? notifier_call_chain+0x2d/0x70 [] ? __blocking_notifier_call_chain+0x4d/0x60 [] ? blocking_notifier_call_chain+0x1a/0x20 [] sys_init_module+0x96/0x1d0 [] ? sys_munmap+0x46/0x60 [] syscall_call+0x7/0xb FIX kmalloc-128: Object at 0xdd59f6e0 not freed rt61pci 0000:00:07.0: PCI INT A disabled rt61pci: probe of 0000:00:07.0 failed with error -2 Signed-off-by: Herton Ronaldo Krzesinski Acked-by: Ivo van Doorn Signed-off-by: John W. Linville --- drivers/net/wireless/rt2x00/rt2x00dev.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/drivers/net/wireless/rt2x00/rt2x00dev.c b/drivers/net/wireless/rt2x00/rt2x00dev.c index 05f94e21b423..5752aaae906b 100644 --- a/drivers/net/wireless/rt2x00/rt2x00dev.c +++ b/drivers/net/wireless/rt2x00/rt2x00dev.c @@ -646,10 +646,8 @@ static int rt2x00lib_probe_hw(struct rt2x00_dev *rt2x00dev) * Register HW. */ status = ieee80211_register_hw(rt2x00dev->hw); - if (status) { - rt2x00lib_remove_hw(rt2x00dev); + if (status) return status; - } set_bit(DEVICE_STATE_REGISTERED_HW, &rt2x00dev->flags); -- 2.20.1