KASAN: use-after-free Read in wdm_out

Title	Rank 🛈	Repro	Cause bisect	Fix bisect	Count	Last	Reported
KASAN: use-after-free Read in wdm_int_callback usb	19	C			6	2532d	2543d
Title	Replies (including bot)	Last reply
KASAN: use-after-free Read in wdm_out_callback	2 (4)	2019/09/20 15:42
Reminder: 52 active syzbot reports in usb subsystem	1 (1)	2019/08/22 03:28
cdc_wdm 1-1:118.0: nonzero urb status received: -71
cdc_wdm 1-1:118.0: wdm_int_callback - 0 bytes
==================================================================
BUG: KASAN: use-after-free in __lock_acquire+0x302a/0x3b50 kernel/locking/lockdep.c:3753
Read of size 8 at addr ffff8881cbdca8e8 by task swapper/0/0

CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.3.0-rc4+ #26
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xca/0x13e lib/dump_stack.c:113
 print_address_description+0x6a/0x32c mm/kasan/report.c:351
 __kasan_report.cold+0x1a/0x33 mm/kasan/report.c:482
 kasan_report+0xe/0x12 mm/kasan/common.c:612
 __lock_acquire+0x302a/0x3b50 kernel/locking/lockdep.c:3753
 lock_acquire+0x127/0x320 kernel/locking/lockdep.c:4412
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x32/0x50 kernel/locking/spinlock.c:159
 wdm_out_callback+0x45/0x170 drivers/usb/class/cdc-wdm.c:148
 __usb_hcd_giveback_urb+0x1f2/0x470 drivers/usb/core/hcd.c:1657
 usb_hcd_giveback_urb+0x368/0x420 drivers/usb/core/hcd.c:1722
 dummy_timer+0x120f/0x2fa2 drivers/usb/gadget/udc/dummy_hcd.c:1965
 call_timer_fn+0x179/0x650 kernel/time/timer.c:1322
 expire_timers kernel/time/timer.c:1366 [inline]
 __run_timers kernel/time/timer.c:1685 [inline]
 __run_timers kernel/time/timer.c:1653 [inline]
 run_timer_softirq+0x5cc/0x14b0 kernel/time/timer.c:1698
 __do_softirq+0x221/0x912 kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x178/0x1a0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:537 [inline]
 smp_apic_timer_interrupt+0x12f/0x500 arch/x86/kernel/apic/apic.c:1095
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830
 </IRQ>
RIP: 0010:default_idle+0x28/0x2e0 arch/x86/kernel/process.c:581
Code: 90 90 41 56 41 55 65 44 8b 2d 64 ea 93 7a 41 54 55 53 0f 1f 44 00 00 e8 96 5b d5 fb e9 07 00 00 00 0f 00 2d 7a 8f 54 00 fb f4 <65> 44 8b 2d 40 ea 93 7a 0f 1f 44 00 00 5b 5d 41 5c 41 5d 41 5e c3
RSP: 0018:ffffffff86c07da8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000007 RBX: ffffffff86c2b200 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000006 RDI: ffffffff86c2ba44
RBP: fffffbfff0d85640 R08: ffffffff86c2b200 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 cpuidle_idle_call kernel/sched/idle.c:154 [inline]
 do_idle+0x3c2/0x4f0 kernel/sched/idle.c:263
 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:354
 start_kernel+0x838/0x872 init/main.c:785
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241

Allocated by task 83:
 save_stack+0x1b/0x80 mm/kasan/common.c:69
 set_track mm/kasan/common.c:77 [inline]
 __kasan_kmalloc mm/kasan/common.c:487 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:460
 kmalloc include/linux/slab.h:552 [inline]
 kzalloc include/linux/slab.h:748 [inline]
 wdm_create+0x56/0x1720 drivers/usb/class/cdc-wdm.c:786
 wdm_probe+0x220/0x2d0 drivers/usb/class/cdc-wdm.c:922
 usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:361
 really_probe+0x281/0x6d0 drivers/base/dd.c:548
 driver_probe_device+0x101/0x1b0 drivers/base/dd.c:721
 __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:828
 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:454
 __device_attach+0x217/0x360 drivers/base/dd.c:894
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514
 device_add+0xae6/0x16f0 drivers/base/core.c:2165
 usb_set_configuration+0xdf6/0x1670 drivers/usb/core/message.c:2023
 generic_probe+0x9d/0xd5 drivers/usb/core/generic.c:210
 usb_probe_device+0x99/0x100 drivers/usb/core/driver.c:266
 really_probe+0x281/0x6d0 drivers/base/dd.c:548
 driver_probe_device+0x101/0x1b0 drivers/base/dd.c:721
 __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:828
 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:454
 __device_attach+0x217/0x360 drivers/base/dd.c:894
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514
 device_add+0xae6/0x16f0 drivers/base/core.c:2165
 usb_new_device.cold+0x6a4/0xe79 drivers/usb/core/hub.c:2536
 hub_port_connect drivers/usb/core/hub.c:5098 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5213 [inline]
 port_event drivers/usb/core/hub.c:5359 [inline]
 hub_event+0x1b5c/0x3640 drivers/usb/core/hub.c:5441
 process_one_work+0x92b/0x1530 kernel/workqueue.c:2269
 worker_thread+0x96/0xe20 kernel/workqueue.c:2415
 kthread+0x318/0x420 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

Freed by task 83:
 save_stack+0x1b/0x80 mm/kasan/common.c:69
 set_track mm/kasan/common.c:77 [inline]
 __kasan_slab_free+0x130/0x180 mm/kasan/common.c:449
 slab_free_hook mm/slub.c:1423 [inline]
 slab_free_freelist_hook mm/slub.c:1474 [inline]
 slab_free mm/slub.c:3016 [inline]
 kfree+0xe4/0x2f0 mm/slub.c:3957
 wdm_create+0x542/0x1720 drivers/usb/class/cdc-wdm.c:884
 wdm_probe+0x220/0x2d0 drivers/usb/class/cdc-wdm.c:922
 usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:361
 really_probe+0x281/0x6d0 drivers/base/dd.c:548
 driver_probe_device+0x101/0x1b0 drivers/base/dd.c:721
 __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:828
 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:454
 __device_attach+0x217/0x360 drivers/base/dd.c:894
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514
 device_add+0xae6/0x16f0 drivers/base/core.c:2165
 usb_set_configuration+0xdf6/0x1670 drivers/usb/core/message.c:2023
 generic_probe+0x9d/0xd5 drivers/usb/core/generic.c:210
 usb_probe_device+0x99/0x100 drivers/usb/core/driver.c:266
 really_probe+0x281/0x6d0 drivers/base/dd.c:548
 driver_probe_device+0x101/0x1b0 drivers/base/dd.c:721
 __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:828
 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:454
 __device_attach+0x217/0x360 drivers/base/dd.c:894
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514
 device_add+0xae6/0x16f0 drivers/base/core.c:2165
 usb_new_device.cold+0x6a4/0xe79 drivers/usb/core/hub.c:2536
 hub_port_connect drivers/usb/core/hub.c:5098 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5213 [inline]
 port_event drivers/usb/core/hub.c:5359 [inline]
 hub_event+0x1b5c/0x3640 drivers/usb/core/hub.c:5441
 process_one_work+0x92b/0x1530 kernel/workqueue.c:2269
 worker_thread+0x96/0xe20 kernel/workqueue.c:2415
 kthread+0x318/0x420 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

The buggy address belongs to the object at ffff8881cbdca880
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 104 bytes inside of
 1024-byte region [ffff8881cbdca880, ffff8881cbdcac80)
The buggy address belongs to the page:
page:ffffea00072f7200 refcount:1 mapcount:0 mapping:ffff8881da002280 index:0x0 compound_mapcount: 0
flags: 0x200000000010200(slab|head)
raw: 0200000000010200 ffffea000719ca00 0000000400000004 ffff8881da002280
raw: 0000000000000000 00000000000e000e 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881cbdca780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881cbdca800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8881cbdca880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                          ^
 ffff8881cbdca900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881cbdca980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================