================================================================== BUG: KASAN: use-after-free in v4l2_release+0x326/0x3b0 drivers/media/v4l2-core/v4l2-dev.c:449 Read of size 8 at addr ffff88811199c398 by task v4l_id/31821 CPU: 1 PID: 31821 Comm: v4l_id Not tainted 5.10.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xae/0x4c8 mm/kasan/report.c:385 __kasan_report mm/kasan/report.c:545 [inline] kasan_report.cold+0x1f/0x37 mm/kasan/report.c:562 v4l2_release+0x326/0x3b0 drivers/media/v4l2-core/v4l2-dev.c:449 __fput+0x28a/0x930 fs/file_table.c:281 task_work_run+0xdd/0x1a0 kernel/task_work.c:151 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop kernel/entry/common.c:164 [inline] exit_to_user_mode_prepare+0x155/0x160 kernel/entry/common.c:191 syscall_exit_to_user_mode+0x38/0x250 kernel/entry/common.c:266 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7fd3bd0c7270 Code: 73 01 c3 48 8b 0d 38 7d 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 59 c1 20 00 00 75 10 b8 03 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 ee fb ff ff 48 89 04 24 RSP: 002b:00007ffe5c42ac48 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007fd3bd0c7270 RDX: 000000000000000a RSI: 00007fd3bd0b3760 RDI: 0000000000000003 RBP: 00007fd3bd6f7698 R08: 00007fd3bd0b3760 R09: 00007fd3bd6f7700 R10: 000056408d73fee3 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe5c42add0 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 31: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xc2/0xd0 mm/kasan/common.c:461 kmalloc include/linux/slab.h:552 [inline] kzalloc include/linux/slab.h:664 [inline] stk_camera_probe+0x7d/0xc50 drivers/media/usb/stkwebcam/stk-webcam.c:1281 usb_probe_interface+0x315/0x7f0 drivers/usb/core/driver.c:396 really_probe+0x291/0xde0 drivers/base/dd.c:554 driver_probe_device+0x26b/0x3d0 drivers/base/dd.c:738 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:844 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:431 __device_attach+0x228/0x4a0 drivers/base/dd.c:912 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0xbb2/0x1ce0 drivers/base/core.c:2936 usb_set_configuration+0x113c/0x1910 drivers/usb/core/message.c:2164 usb_generic_driver_probe+0xba/0x100 drivers/usb/core/generic.c:238 usb_probe_device+0xd9/0x2c0 drivers/usb/core/driver.c:293 really_probe+0x291/0xde0 drivers/base/dd.c:554 driver_probe_device+0x26b/0x3d0 drivers/base/dd.c:738 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:844 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:431 __device_attach+0x228/0x4a0 drivers/base/dd.c:912 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0xbb2/0x1ce0 drivers/base/core.c:2936 usb_new_device.cold+0x71d/0xfe9 drivers/usb/core/hub.c:2555 hub_port_connect drivers/usb/core/hub.c:5223 [inline] hub_port_connect_change drivers/usb/core/hub.c:5363 [inline] port_event drivers/usb/core/hub.c:5509 [inline] hub_event+0x2348/0x42d0 drivers/usb/core/hub.c:5591 process_one_work+0x933/0x1520 kernel/workqueue.c:2272 worker_thread+0x64c/0x1120 kernel/workqueue.c:2418 kthread+0x38c/0x460 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Freed by task 7171: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track+0x1c/0x30 mm/kasan/common.c:56 kasan_set_free_info+0x1b/0x30 mm/kasan/generic.c:355 __kasan_slab_free+0x102/0x140 mm/kasan/common.c:422 slab_free_hook mm/slub.c:1544 [inline] slab_free_freelist_hook+0x5d/0x150 mm/slub.c:1577 slab_free mm/slub.c:3142 [inline] kfree+0xe5/0x5e0 mm/slub.c:4124 usb_unbind_interface+0x1d8/0x8d0 drivers/usb/core/driver.c:458 __device_release_driver+0x3bd/0x6f0 drivers/base/dd.c:1154 device_release_driver_internal drivers/base/dd.c:1185 [inline] device_release_driver+0x26/0x40 drivers/base/dd.c:1208 bus_remove_device+0x2eb/0x5a0 drivers/base/bus.c:533 device_del+0x502/0xec0 drivers/base/core.c:3115 usb_disable_device+0x35b/0x7b0 drivers/usb/core/message.c:1413 usb_disconnect.cold+0x27d/0x780 drivers/usb/core/hub.c:2218 hub_port_connect drivers/usb/core/hub.c:5074 [inline] hub_port_connect_change drivers/usb/core/hub.c:5363 [inline] port_event drivers/usb/core/hub.c:5509 [inline] hub_event+0x1c8a/0x42d0 drivers/usb/core/hub.c:5591 process_one_work+0x933/0x1520 kernel/workqueue.c:2272 worker_thread+0x64c/0x1120 kernel/workqueue.c:2418 kthread+0x38c/0x460 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 The buggy address belongs to the object at ffff88811199c000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 920 bytes inside of 4096-byte region [ffff88811199c000, ffff88811199d000) The buggy address belongs to the page: page:000000006cc9cfe6 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x111998 head:000000006cc9cfe6 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x200000000010200(slab|head) raw: 0200000000010200 0000000000000000 0000000100000001 ffff888100042140 raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88811199c280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88811199c300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88811199c380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88811199c400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88811199c480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================