usb 6-1: USB disconnect, device number 2 ================================================================== BUG: KASAN: slab-use-after-free in hdm_disconnect+0x10d/0x1c0 drivers/most/most_usb.c:1125 Read of size 8 at addr ffff88805b9ed898 by task kworker/1:0/23 CPU: 1 PID: 23 Comm: kworker/1:0 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: usb_hub_wq hub_event Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xac/0x220 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 hdm_disconnect+0x10d/0x1c0 drivers/most/most_usb.c:1125 usb_unbind_interface+0x1f2/0x870 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:569 [inline] __device_release_driver drivers/base/dd.c:1272 [inline] device_release_driver_internal+0x4cb/0x7a0 drivers/base/dd.c:1295 bus_remove_device+0x342/0x400 drivers/base/bus.c:576 device_del+0x50b/0x900 drivers/base/core.c:3872 usb_disable_device+0x3e9/0x8a0 drivers/usb/core/message.c:1416 usb_disconnect+0x34c/0x8a0 drivers/usb/core/hub.c:2315 hub_port_connect drivers/usb/core/hub.c:5369 [inline] hub_port_connect_change drivers/usb/core/hub.c:5669 [inline] port_event drivers/usb/core/hub.c:5833 [inline] hub_event+0x1cef/0x49c0 drivers/usb/core/hub.c:5915 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Allocated by task 23: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] hdm_probe+0x96/0x13e0 drivers/most/most_usb.c:959 usb_probe_interface+0x5a4/0xb00 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x25b/0xb40 drivers/base/dd.c:658 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:800 driver_probe_device+0x4f/0x420 drivers/base/dd.c:830 __device_attach_driver+0x2ca/0x520 drivers/base/dd.c:958 bus_for_each_drv+0x24b/0x2d0 drivers/base/bus.c:459 __device_attach+0x2b5/0x400 drivers/base/dd.c:1030 bus_probe_device+0x180/0x260 drivers/base/bus.c:534 device_add+0x85b/0xc20 drivers/base/core.c:3683 usb_set_configuration+0x1a79/0x20c0 drivers/usb/core/message.c:2207 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:238 usb_probe_device+0x13d/0x280 drivers/usb/core/driver.c:293 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x25b/0xb40 drivers/base/dd.c:658 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:800 driver_probe_device+0x4f/0x420 drivers/base/dd.c:830 __device_attach_driver+0x2ca/0x520 drivers/base/dd.c:958 bus_for_each_drv+0x24b/0x2d0 drivers/base/bus.c:459 __device_attach+0x2b5/0x400 drivers/base/dd.c:1030 bus_probe_device+0x180/0x260 drivers/base/bus.c:534 device_add+0x85b/0xc20 drivers/base/core.c:3683 usb_new_device+0xa31/0x1630 drivers/usb/core/hub.c:2660 hub_port_connect drivers/usb/core/hub.c:5529 [inline] hub_port_connect_change drivers/usb/core/hub.c:5669 [inline] port_event drivers/usb/core/hub.c:5833 [inline] hub_event+0x2962/0x49c0 drivers/usb/core/hub.c:5915 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Freed by task 23: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1811 [inline] slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] __kmem_cache_free+0xba/0x1f0 mm/slub.c:3843 device_release+0x96/0x1c0 drivers/base/core.c:-1 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x221/0x470 lib/kobject.c:737 hdm_disconnect+0xf3/0x1c0 drivers/most/most_usb.c:1123 usb_unbind_interface+0x1f2/0x870 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:569 [inline] __device_release_driver drivers/base/dd.c:1272 [inline] device_release_driver_internal+0x4cb/0x7a0 drivers/base/dd.c:1295 bus_remove_device+0x342/0x400 drivers/base/bus.c:576 device_del+0x50b/0x900 drivers/base/core.c:3872 usb_disable_device+0x3e9/0x8a0 drivers/usb/core/message.c:1416 usb_disconnect+0x34c/0x8a0 drivers/usb/core/hub.c:2315 hub_port_connect drivers/usb/core/hub.c:5369 [inline] hub_port_connect_change drivers/usb/core/hub.c:5669 [inline] port_event drivers/usb/core/hub.c:5833 [inline] hub_event+0x1cef/0x49c0 drivers/usb/core/hub.c:5915 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 insert_work+0x3d/0x310 kernel/workqueue.c:1651 __queue_work+0xc39/0x1020 kernel/workqueue.c:1800 queue_work_on+0x121/0x1e0 kernel/workqueue.c:1835 kref_put include/linux/kref.h:65 [inline] sg_release+0x1b6/0x2b0 drivers/scsi/sg.c:400 __fput+0x234/0x970 fs/file_table.c:384 task_work_run+0x1ce/0x250 kernel/task_work.c:239 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xf6/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Second to last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 insert_work+0x3d/0x310 kernel/workqueue.c:1651 __queue_work+0xc39/0x1020 kernel/workqueue.c:1800 queue_work_on+0x121/0x1e0 kernel/workqueue.c:1835 queue_work include/linux/workqueue.h:562 [inline] schedule_work include/linux/workqueue.h:623 [inline] f2fs_handle_critical_error+0x58e/0x900 fs/f2fs/super.c:4145 f2fs_write_end_io+0x52b/0x8a0 fs/f2fs/data.c:353 __submit_merged_bio+0x256/0x630 fs/f2fs/data.c:539 __f2fs_submit_merged_write fs/f2fs/data.c:632 [inline] __submit_merged_write_cond+0x449/0x520 fs/f2fs/data.c:654 f2fs_sync_node_pages+0x13ef/0x1560 fs/f2fs/node.c:2107 f2fs_write_node_pages+0x315/0x6b0 fs/f2fs/node.c:2179 do_writepages+0x3a2/0x600 mm/page-writeback.c:2575 __writeback_single_inode+0x153/0xee0 fs/fs-writeback.c:1635 writeback_sb_inodes+0x77c/0xef0 fs/fs-writeback.c:1926 wb_writeback+0x450/0xba0 fs/fs-writeback.c:2105 wb_do_writeback fs/fs-writeback.c:2252 [inline] wb_workfn+0x3ff/0xe20 fs/fs-writeback.c:2292 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 The buggy address belongs to the object at ffff88805b9ec000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 6296 bytes inside of freed 8192-byte region [ffff88805b9ec000, ffff88805b9ee000) The buggy address belongs to the physical page: page:ffffea00016e7a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5b9e8 head:ffffea00016e7a00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888017842280 ffffea00017cc800 dead000000000004 raw: 0000000000000000 0000000080020002 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 7026, tgid 7026 (syz-executor), ts 195937719288, free_ts 195744749271 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554 prep_new_page mm/page_alloc.c:1561 [inline] get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457 alloc_slab_page+0x5d/0x170 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2e0 mm/slub.c:2081 ___slab_alloc+0xc6d/0x1300 mm/slub.c:3253 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x1a2/0x260 mm/slub.c:3534 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0xa4/0x240 mm/slab_common.c:1020 kmalloc_array include/linux/slab.h:637 [inline] kcalloc include/linux/slab.h:668 [inline] cache_create_net+0x92/0x250 net/sunrpc/cache.c:1747 rsc_cache_create_net net/sunrpc/auth_gss/svcauth_gss.c:2056 [inline] gss_svc_init_net+0x58/0x560 net/sunrpc/auth_gss/svcauth_gss.c:2084 ops_init+0x397/0x640 net/core/net_namespace.c:139 setup_net+0x3a5/0xa00 net/core/net_namespace.c:343 copy_net_ns+0x36d/0x5e0 net/core/net_namespace.c:520 create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x11a/0x160 kernel/nsproxy.c:228 ksys_unshare+0x4c0/0x890 kernel/fork.c:3439 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1154 [inline] free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429 discard_slab mm/slub.c:2127 [inline] __unfreeze_partials+0x1cf/0x210 mm/slub.c:2667 put_cpu_partial+0x17c/0x250 mm/slub.c:2743 __slab_free+0x31d/0x410 mm/slub.c:3700 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc+0x11e/0x2e0 mm/slub.c:3519 getname_flags+0xbb/0x500 fs/namei.c:140 vfs_fstatat+0x111/0x1b0 fs/stat.c:298 __do_sys_newfstatat fs/stat.c:463 [inline] __se_sys_newfstatat fs/stat.c:457 [inline] __x64_sys_newfstatat+0x117/0x190 fs/stat.c:457 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff88805b9ed780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805b9ed800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805b9ed880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805b9ed900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805b9ed980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================