• Herton Ronaldo Krzesinski's avatar
    rt2x00: prevent double kfree when failing to register hardware · f05faa31
    Herton Ronaldo Krzesinski authored
    
    
    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:
     [<c01abbb3>] print_trailer+0xd3/0x120
     [<c01abd37>] object_err+0x37/0x50
     [<c01acf57>] __slab_free+0xe7/0x2f0
     [<c01ad1de>] kfree+0x7e/0xd0
     [<e0e4a239>] ? rt2x00lib_remove_hw+0x59/0x70 [rt2x00lib]
     [<e0e4a239>] ? rt2x00lib_remove_hw+0x59/0x70 [rt2x00lib]
     [<e0e4a239>] rt2x00lib_remove_hw+0x59/0x70 [rt2x00lib]
     [<e0e4acc7>] rt2x00lib_remove_dev+0x37/0x50 [rt2x00lib]
     [<e0e4b087>] rt2x00lib_probe_dev+0x1a7/0x3b0 [rt2x00lib]
     [<e0eb288f>] rt2x00pci_probe+0xdf/0x1ee [rt2x00pci]
     [<c026b9ee>] local_pci_probe+0xe/0x10
     [<c026c750>] pci_device_probe+0x60/0x80
     [<c02d5c2a>] driver_probe_device+0x9a/0x2e0
     [<c02d5ef9>] __driver_attach+0x89/0x90
     [<c02d541b>] bus_for_each_dev+0x4b/0x70
     [<c026c690>] ? pci_device_remove+0x0/0x40
     [<c02d59d9>] driver_attach+0x19/0x20
     [<c02d5e70>] ? __driver_attach+0x0/0x90
     [<c02d4cef>] bus_add_driver+0x1cf/0x2a0
     [<c026c690>] ? pci_device_remove+0x0/0x40
     [<c02d60c9>] driver_register+0x69/0x140
     [<c026c9b0>] __pci_register_driver+0x40/0x80
     [<e0ecc000>] ? rt61pci_init+0x0/0x19 [rt61pci]
     [<e0ecc017>] rt61pci_init+0x17/0x19 [rt61pci]
     [<c0101116>] do_one_initcall+0x26/0x1c0
     [<c01ab90c>] ? slab_pad_check+0x3c/0x120
     [<c01ab90c>] ? slab_pad_check+0x3c/0x120
     [<c01ac8da>] ? check_object+0xda/0x210
     [<c01b0026>] ? percpu_free+0x46/0x50
     [<c01ad09e>] ? __slab_free+0x22e/0x2f0
     [<c01b0026>] ? percpu_free+0x46/0x50
     [<c01b0026>] ? percpu_free+0x46/0x50
     [<c01b0026>] ? percpu_free+0x46/0x50
     [<c01687ec>] ? stop_machine_destroy+0x3c/0x40
     [<c015e515>] ? load_module+0xa5/0x1c50
     [<e0ec5000>] ? rt61pci_eepromregister_read+0x0/0x40 [rt61pci]
     [<e0eb2000>] ? rt2x00pci_write_tx_data+0x0/0x90 [rt2x00pci]
     [<c03ac2fb>] ? mutex_lock+0xb/0x20
     [<c03ac2fb>] ? mutex_lock+0xb/0x20
     [<c017ad16>] ? tracepoint_update_probe_range+0x76/0xa0
     [<c017ad6f>] ? tracepoint_module_notify+0x2f/0x40
     [<c03b02ed>] ? notifier_call_chain+0x2d/0x70
     [<c014f0ed>] ? __blocking_notifier_call_chain+0x4d/0x60
     [<c014f11a>] ? blocking_notifier_call_chain+0x1a/0x20
     [<c0160156>] sys_init_module+0x96/0x1d0
     [<c019dad6>] ? sys_munmap+0x46/0x60
     [<c0105546>] 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: default avatarHerton Ronaldo Krzesinski <herton@mandriva.com.br>
    Acked-by: default avatarIvo van Doorn <IvDoorn@gmail.com>
    Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
    f05faa31
rt2x00dev.c 22.5 KB