================================================================== BUG: KASAN: use-after-free in v4l2_fh_init+0x279/0x2c0 drivers/media/v4l2-core/v4l2-fh.c:25 Read of size 8 at addr ffff88802ceb48a8 by task v4l_id/12137 CPU: 0 PID: 12137 Comm: v4l_id Not tainted 5.13.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:233 __kasan_report mm/kasan/report.c:419 [inline] kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:436 v4l2_fh_init+0x279/0x2c0 drivers/media/v4l2-core/v4l2-fh.c:25 v4l2_fh_open+0x88/0xc0 drivers/media/v4l2-core/v4l2-fh.c:63 v4l_stk_open+0x12e/0x280 drivers/media/usb/stkwebcam/stk-webcam.c:626 v4l2_open+0x21c/0x3f0 drivers/media/v4l2-core/v4l2-dev.c:429 chrdev_open+0x266/0x770 fs/char_dev.c:414 do_dentry_open+0x4b9/0x11b0 fs/open.c:826 do_open fs/namei.c:3361 [inline] path_openat+0x1c0e/0x27e0 fs/namei.c:3494 do_filp_open+0x190/0x3d0 fs/namei.c:3521 do_sys_openat2+0x16d/0x420 fs/open.c:1187 do_sys_open fs/open.c:1203 [inline] __do_sys_open fs/open.c:1211 [inline] __se_sys_open fs/open.c:1207 [inline] __x64_sys_open+0x119/0x1c0 fs/open.c:1207 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f9ab74db840 Code: 73 01 c3 48 8b 0d 68 77 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 bb 20 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24 RSP: 002b:00007ffc3b40a9d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007ffc3b40ab48 RCX: 00007f9ab74db840 RDX: 00007f9ab74c7ea0 RSI: 0000000000000000 RDI: 00007ffc3b40af1e RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000000b R11: 0000000000000246 R12: 000055d32aa5f8d0 R13: 00007ffc3b40ab40 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 9727: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:428 [inline] ____kasan_kmalloc mm/kasan/common.c:507 [inline] ____kasan_kmalloc mm/kasan/common.c:466 [inline] __kasan_kmalloc+0x9b/0xd0 mm/kasan/common.c:516 kmalloc include/linux/slab.h:556 [inline] kzalloc include/linux/slab.h:686 [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+0x291/0xf60 drivers/base/dd.c:576 driver_probe_device+0x298/0x410 drivers/base/dd.c:763 __device_attach_driver+0x203/0x2c0 drivers/base/dd.c:870 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:431 __device_attach+0x228/0x4b0 drivers/base/dd.c:938 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0xbe0/0x2100 drivers/base/core.c:3324 usb_set_configuration+0x113f/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+0x291/0xf60 drivers/base/dd.c:576 driver_probe_device+0x298/0x410 drivers/base/dd.c:763 __device_attach_driver+0x203/0x2c0 drivers/base/dd.c:870 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:431 __device_attach+0x228/0x4b0 drivers/base/dd.c:938 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0xbe0/0x2100 drivers/base/core.c:3324 usb_new_device.cold+0x721/0x1058 drivers/usb/core/hub.c:2556 hub_port_connect drivers/usb/core/hub.c:5276 [inline] hub_port_connect_change drivers/usb/core/hub.c:5416 [inline] port_event drivers/usb/core/hub.c:5562 [inline] hub_event+0x2357/0x4330 drivers/usb/core/hub.c:5644 process_one_work+0x98d/0x1600 kernel/workqueue.c:2276 worker_thread+0x64c/0x1120 kernel/workqueue.c:2422 kthread+0x3b1/0x4a0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Freed by task 9701: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:357 ____kasan_slab_free mm/kasan/common.c:360 [inline] ____kasan_slab_free mm/kasan/common.c:325 [inline] __kasan_slab_free+0xfb/0x130 mm/kasan/common.c:368 kasan_slab_free include/linux/kasan.h:212 [inline] slab_free_hook mm/slub.c:1582 [inline] slab_free_freelist_hook+0xdf/0x240 mm/slub.c:1607 slab_free mm/slub.c:3167 [inline] kfree+0xe5/0x7f0 mm/slub.c:4217 usb_unbind_interface+0x1d8/0x8d0 drivers/usb/core/driver.c:458 __device_release_driver+0x3bd/0x6f0 drivers/base/dd.c:1181 device_release_driver_internal drivers/base/dd.c:1212 [inline] device_release_driver+0x26/0x40 drivers/base/dd.c:1235 bus_remove_device+0x2eb/0x5a0 drivers/base/bus.c:533 device_del+0x502/0xd40 drivers/base/core.c:3512 usb_disable_device+0x35b/0x7b0 drivers/usb/core/message.c:1413 usb_disconnect.cold+0x27d/0x791 drivers/usb/core/hub.c:2219 hub_port_connect drivers/usb/core/hub.c:5127 [inline] hub_port_connect_change drivers/usb/core/hub.c:5416 [inline] port_event drivers/usb/core/hub.c:5562 [inline] hub_event+0x1c9c/0x4330 drivers/usb/core/hub.c:5644 process_one_work+0x98d/0x1600 kernel/workqueue.c:2276 worker_thread+0x64c/0x1120 kernel/workqueue.c:2422 kthread+0x3b1/0x4a0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 The buggy address belongs to the object at ffff88802ceb4000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 2216 bytes inside of 4096-byte region [ffff88802ceb4000, ffff88802ceb5000) The buggy address belongs to the page: page:ffffea0000b3ac00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2ceb0 head:ffffea0000b3ac00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888011042140 raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 6425, ts 38540831197, free_ts 38498398889 prep_new_page mm/page_alloc.c:2358 [inline] get_page_from_freelist+0x1033/0x2b60 mm/page_alloc.c:3994 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5200 alloc_pages+0x18c/0x2a0 mm/mempolicy.c:2272 alloc_slab_page mm/slub.c:1645 [inline] allocate_slab+0x2c5/0x4c0 mm/slub.c:1785 new_slab mm/slub.c:1848 [inline] new_slab_objects mm/slub.c:2594 [inline] ___slab_alloc+0x4a1/0x810 mm/slub.c:2757 __slab_alloc.constprop.0+0xa7/0xf0 mm/slub.c:2797 slab_alloc_node mm/slub.c:2879 [inline] slab_alloc mm/slub.c:2921 [inline] __kmalloc+0x315/0x330 mm/slub.c:4055 kmalloc include/linux/slab.h:561 [inline] tomoyo_realpath_from_path+0xc3/0x620 security/tomoyo/realpath.c:254 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x272/0x380 security/tomoyo/file.c:771 tomoyo_file_open security/tomoyo/tomoyo.c:313 [inline] tomoyo_file_open+0xa3/0xd0 security/tomoyo/tomoyo.c:308 security_file_open+0x52/0x4f0 security/security.c:1633 do_dentry_open+0x358/0x11b0 fs/open.c:813 do_open fs/namei.c:3361 [inline] path_openat+0x1c0e/0x27e0 fs/namei.c:3494 do_filp_open+0x190/0x3d0 fs/namei.c:3521 do_sys_openat2+0x16d/0x420 fs/open.c:1187 do_sys_open fs/open.c:1203 [inline] __do_sys_open fs/open.c:1211 [inline] __se_sys_open fs/open.c:1207 [inline] __x64_sys_open+0x119/0x1c0 fs/open.c:1207 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1298 [inline] __free_pages_ok+0x476/0xce0 mm/page_alloc.c:1572 qlink_free mm/kasan/quarantine.c:146 [inline] qlist_free_all+0x5a/0xc0 mm/kasan/quarantine.c:165 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272 __kasan_slab_alloc+0x8e/0xa0 mm/kasan/common.c:438 kasan_slab_alloc include/linux/kasan.h:236 [inline] slab_post_alloc_hook mm/slab.h:524 [inline] slab_alloc_node mm/slub.c:2913 [inline] slab_alloc mm/slub.c:2921 [inline] kmem_cache_alloc+0x219/0x3a0 mm/slub.c:2926 prepare_kernel_cred+0x23/0x800 kernel/cred.c:687 call_usermodehelper_exec_async+0x10e/0x580 kernel/umh.c:91 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Memory state around the buggy address: ffff88802ceb4780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802ceb4800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802ceb4880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802ceb4900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802ceb4980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================