* usb: mon: freeing active timer @ 2014-04-24 17:40 Sasha Levin 2014-04-24 19:24 ` Greg KH 0 siblings, 1 reply; 4+ messages in thread From: Sasha Levin @ 2014-04-24 17:40 UTC (permalink / raw) To: linux-usb; +Cc: Greg KH, Dave Jones, LKML Hi all, While fuzzing with trinity inside a KVM tools guest running the latest -next kernel I've stumbled on the following: [ 1361.390880] WARNING: CPU: 10 PID: 24274 at lib/debugobjects.c:260 debug_print_object+0x8c/0xb0() [ 1361.391203] ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x20 [ 1361.391203] Modules linked in: [ 1361.391203] CPU: 10 PID: 24274 Comm: trinity-c83 Not tainted 3.15.0-rc2-next-20140423-sasha-00018-gc4ff6c4 #408 [ 1361.391203] 0000000000000009 ffff8801de341c78 ffffffffb85271f2 0000000000000001 [ 1361.391203] ffff8801de341cc8 ffff8801de341cb8 ffffffffb515afcc ffff8801eb3ebd98 [ 1361.391203] ffff8801eb751870 ffffffffb9e76200 ffffffffb98dc502 ffffffffbc702550 [ 1361.391203] Call Trace: [ 1361.391203] dump_stack (lib/dump_stack.c:52) [ 1361.391203] warn_slowpath_common (kernel/panic.c:430) [ 1361.391203] warn_slowpath_fmt (kernel/panic.c:445) [ 1361.391203] debug_print_object (lib/debugobjects.c:262) [ 1361.391203] ? __queue_work (kernel/workqueue.c:1452) [ 1361.391203] __debug_check_no_obj_freed (lib/debugobjects.c:697) [ 1361.391203] debug_check_no_obj_freed (lib/debugobjects.c:726) [ 1361.391203] kmem_cache_free (mm/slub.c:2689 mm/slub.c:2717) [ 1361.391203] ? kmem_cache_destroy (mm/slab_common.c:363) [ 1361.391203] kmem_cache_destroy (mm/slab_common.c:363) [ 1361.391203] mon_text_release (drivers/usb/mon/mon_text.c:643) [ 1361.391203] __fput (fs/file_table.c:217) [ 1361.391203] ____fput (fs/file_table.c:253) [ 1361.391203] task_work_run (kernel/task_work.c:125 (discriminator 1)) [ 1361.391203] do_notify_resume (include/linux/tracehook.h:196 arch/x86/kernel/signal.c:751) [ 1361.391203] int_signal (arch/x86/kernel/entry_64.S:807) Thanks, Sasha ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: usb: mon: freeing active timer 2014-04-24 17:40 usb: mon: freeing active timer Sasha Levin @ 2014-04-24 19:24 ` Greg KH 2014-04-24 19:35 ` Sasha Levin 0 siblings, 1 reply; 4+ messages in thread From: Greg KH @ 2014-04-24 19:24 UTC (permalink / raw) To: Sasha Levin; +Cc: linux-usb, Dave Jones, LKML On Thu, Apr 24, 2014 at 01:40:14PM -0400, Sasha Levin wrote: > Hi all, > > While fuzzing with trinity inside a KVM tools guest running the latest -next > kernel I've stumbled on the following: > > [ 1361.390880] WARNING: CPU: 10 PID: 24274 at lib/debugobjects.c:260 debug_print_object+0x8c/0xb0() > [ 1361.391203] ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x20 > [ 1361.391203] Modules linked in: > [ 1361.391203] CPU: 10 PID: 24274 Comm: trinity-c83 Not tainted 3.15.0-rc2-next-20140423-sasha-00018-gc4ff6c4 #408 > [ 1361.391203] 0000000000000009 ffff8801de341c78 ffffffffb85271f2 0000000000000001 > [ 1361.391203] ffff8801de341cc8 ffff8801de341cb8 ffffffffb515afcc ffff8801eb3ebd98 > [ 1361.391203] ffff8801eb751870 ffffffffb9e76200 ffffffffb98dc502 ffffffffbc702550 > [ 1361.391203] Call Trace: > [ 1361.391203] dump_stack (lib/dump_stack.c:52) > [ 1361.391203] warn_slowpath_common (kernel/panic.c:430) > [ 1361.391203] warn_slowpath_fmt (kernel/panic.c:445) > [ 1361.391203] debug_print_object (lib/debugobjects.c:262) > [ 1361.391203] ? __queue_work (kernel/workqueue.c:1452) > [ 1361.391203] __debug_check_no_obj_freed (lib/debugobjects.c:697) > [ 1361.391203] debug_check_no_obj_freed (lib/debugobjects.c:726) > [ 1361.391203] kmem_cache_free (mm/slub.c:2689 mm/slub.c:2717) > [ 1361.391203] ? kmem_cache_destroy (mm/slab_common.c:363) > [ 1361.391203] kmem_cache_destroy (mm/slab_common.c:363) > [ 1361.391203] mon_text_release (drivers/usb/mon/mon_text.c:643) > [ 1361.391203] __fput (fs/file_table.c:217) > [ 1361.391203] ____fput (fs/file_table.c:253) > [ 1361.391203] task_work_run (kernel/task_work.c:125 (discriminator 1)) > [ 1361.391203] do_notify_resume (include/linux/tracehook.h:196 arch/x86/kernel/signal.c:751) > [ 1361.391203] int_signal (arch/x86/kernel/entry_64.S:807) So you were running usbmon at the time? Were you actually monitoring a specific USB device/bus, or something else? thanks, greg k-h ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: usb: mon: freeing active timer 2014-04-24 19:24 ` Greg KH @ 2014-04-24 19:35 ` Sasha Levin 2014-04-24 19:54 ` Alan Stern 0 siblings, 1 reply; 4+ messages in thread From: Sasha Levin @ 2014-04-24 19:35 UTC (permalink / raw) To: Greg KH; +Cc: linux-usb, Dave Jones, LKML On 04/24/2014 03:24 PM, Greg KH wrote: > On Thu, Apr 24, 2014 at 01:40:14PM -0400, Sasha Levin wrote: >> > Hi all, >> > >> > While fuzzing with trinity inside a KVM tools guest running the latest -next >> > kernel I've stumbled on the following: >> > >> > [ 1361.390880] WARNING: CPU: 10 PID: 24274 at lib/debugobjects.c:260 debug_print_object+0x8c/0xb0() >> > [ 1361.391203] ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x20 >> > [ 1361.391203] Modules linked in: >> > [ 1361.391203] CPU: 10 PID: 24274 Comm: trinity-c83 Not tainted 3.15.0-rc2-next-20140423-sasha-00018-gc4ff6c4 #408 >> > [ 1361.391203] 0000000000000009 ffff8801de341c78 ffffffffb85271f2 0000000000000001 >> > [ 1361.391203] ffff8801de341cc8 ffff8801de341cb8 ffffffffb515afcc ffff8801eb3ebd98 >> > [ 1361.391203] ffff8801eb751870 ffffffffb9e76200 ffffffffb98dc502 ffffffffbc702550 >> > [ 1361.391203] Call Trace: >> > [ 1361.391203] dump_stack (lib/dump_stack.c:52) >> > [ 1361.391203] warn_slowpath_common (kernel/panic.c:430) >> > [ 1361.391203] warn_slowpath_fmt (kernel/panic.c:445) >> > [ 1361.391203] debug_print_object (lib/debugobjects.c:262) >> > [ 1361.391203] ? __queue_work (kernel/workqueue.c:1452) >> > [ 1361.391203] __debug_check_no_obj_freed (lib/debugobjects.c:697) >> > [ 1361.391203] debug_check_no_obj_freed (lib/debugobjects.c:726) >> > [ 1361.391203] kmem_cache_free (mm/slub.c:2689 mm/slub.c:2717) >> > [ 1361.391203] ? kmem_cache_destroy (mm/slab_common.c:363) >> > [ 1361.391203] kmem_cache_destroy (mm/slab_common.c:363) >> > [ 1361.391203] mon_text_release (drivers/usb/mon/mon_text.c:643) >> > [ 1361.391203] __fput (fs/file_table.c:217) >> > [ 1361.391203] ____fput (fs/file_table.c:253) >> > [ 1361.391203] task_work_run (kernel/task_work.c:125 (discriminator 1)) >> > [ 1361.391203] do_notify_resume (include/linux/tracehook.h:196 arch/x86/kernel/signal.c:751) >> > [ 1361.391203] int_signal (arch/x86/kernel/entry_64.S:807) > So you were running usbmon at the time? Were you actually monitoring a > specific USB device/bus, or something else? This was inside a vm with no actual physical USB devices: # lsusb -t lsusb: cannot open "/var/lib/usbutils/usb.ids", No such file or directory /: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=ozwpan/8p, 12M /: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=dummy_hcd/1p, 480M |__ Port 1: Dev 2, If 0, Class=comm., Driver=cdc_eem, 480M Since it happened while I was fuzzing, I'm not sure what exactly was getting monitored at that point. Thanks, Sasha ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: usb: mon: freeing active timer 2014-04-24 19:35 ` Sasha Levin @ 2014-04-24 19:54 ` Alan Stern 0 siblings, 0 replies; 4+ messages in thread From: Alan Stern @ 2014-04-24 19:54 UTC (permalink / raw) To: Sasha Levin; +Cc: Greg KH, linux-usb, Dave Jones, LKML On Thu, 24 Apr 2014, Sasha Levin wrote: > On 04/24/2014 03:24 PM, Greg KH wrote: > > On Thu, Apr 24, 2014 at 01:40:14PM -0400, Sasha Levin wrote: > >> > Hi all, > >> > > >> > While fuzzing with trinity inside a KVM tools guest running the latest -next > >> > kernel I've stumbled on the following: > >> > > >> > [ 1361.390880] WARNING: CPU: 10 PID: 24274 at lib/debugobjects.c:260 debug_print_object+0x8c/0xb0() > >> > [ 1361.391203] ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x20 > >> > [ 1361.391203] Modules linked in: > >> > [ 1361.391203] CPU: 10 PID: 24274 Comm: trinity-c83 Not tainted 3.15.0-rc2-next-20140423-sasha-00018-gc4ff6c4 #408 > >> > [ 1361.391203] 0000000000000009 ffff8801de341c78 ffffffffb85271f2 0000000000000001 > >> > [ 1361.391203] ffff8801de341cc8 ffff8801de341cb8 ffffffffb515afcc ffff8801eb3ebd98 > >> > [ 1361.391203] ffff8801eb751870 ffffffffb9e76200 ffffffffb98dc502 ffffffffbc702550 > >> > [ 1361.391203] Call Trace: > >> > [ 1361.391203] dump_stack (lib/dump_stack.c:52) > >> > [ 1361.391203] warn_slowpath_common (kernel/panic.c:430) > >> > [ 1361.391203] warn_slowpath_fmt (kernel/panic.c:445) > >> > [ 1361.391203] debug_print_object (lib/debugobjects.c:262) > >> > [ 1361.391203] ? __queue_work (kernel/workqueue.c:1452) > >> > [ 1361.391203] __debug_check_no_obj_freed (lib/debugobjects.c:697) > >> > [ 1361.391203] debug_check_no_obj_freed (lib/debugobjects.c:726) > >> > [ 1361.391203] kmem_cache_free (mm/slub.c:2689 mm/slub.c:2717) > >> > [ 1361.391203] ? kmem_cache_destroy (mm/slab_common.c:363) > >> > [ 1361.391203] kmem_cache_destroy (mm/slab_common.c:363) > >> > [ 1361.391203] mon_text_release (drivers/usb/mon/mon_text.c:643) > >> > [ 1361.391203] __fput (fs/file_table.c:217) > >> > [ 1361.391203] ____fput (fs/file_table.c:253) > >> > [ 1361.391203] task_work_run (kernel/task_work.c:125 (discriminator 1)) > >> > [ 1361.391203] do_notify_resume (include/linux/tracehook.h:196 arch/x86/kernel/signal.c:751) > >> > [ 1361.391203] int_signal (arch/x86/kernel/entry_64.S:807) > > So you were running usbmon at the time? Were you actually monitoring a > > specific USB device/bus, or something else? > > This was inside a vm with no actual physical USB devices: > > # lsusb -t > lsusb: cannot open "/var/lib/usbutils/usb.ids", No such file or directory > /: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=ozwpan/8p, 12M > /: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=dummy_hcd/1p, 480M > |__ Port 1: Dev 2, If 0, Class=comm., Driver=cdc_eem, 480M > > Since it happened while I was fuzzing, I'm not sure what exactly was getting > monitored at that point. This is odd because the warning message indicates the something containing an active timer (a delayed_work structure?) was deallocated. But usbmon doesn't use either timers or work queues, and as far as I can see, neither does anything involved in kmem_cache management. Alan Stern ^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2014-04-24 19:54 UTC | newest] Thread overview: 4+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2014-04-24 17:40 usb: mon: freeing active timer Sasha Levin 2014-04-24 19:24 ` Greg KH 2014-04-24 19:35 ` Sasha Levin 2014-04-24 19:54 ` Alan Stern
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