usb 4-1: USB disconnect, device number 29 ================================================================== BUG: KASAN: use-after-free in hdm_disconnect+0x109/0x1c0 drivers/most/most_usb.c:1125 Read of size 8 at addr ffff88807c459898 by task kworker/0:4/4311 CPU: 0 PID: 4311 Comm: kworker/0:4 Not tainted 6.1.147-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: usb_hub_wq hub_event Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x200 mm/kasan/report.c:418 kasan_report+0x10b/0x140 mm/kasan/report.c:522 hdm_disconnect+0x109/0x1c0 drivers/most/most_usb.c:1125 usb_unbind_interface+0x1ee/0x860 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:550 [inline] __device_release_driver drivers/base/dd.c:1260 [inline] device_release_driver_internal+0x522/0x850 drivers/base/dd.c:1286 bus_remove_device+0x2e2/0x400 drivers/base/bus.c:531 device_del+0x628/0xa70 drivers/base/core.c:3885 usb_disable_device+0x3e2/0x890 drivers/usb/core/message.c:1414 usb_disconnect+0x348/0x8a0 drivers/usb/core/hub.c:2314 hub_port_connect drivers/usb/core/hub.c:5361 [inline] hub_port_connect_change drivers/usb/core/hub.c:5657 [inline] port_event drivers/usb/core/hub.c:5817 [inline] hub_event+0x1e24/0x54e0 drivers/usb/core/hub.c:5899 process_one_work+0x898/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 6769: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] hdm_probe+0x8f/0x13d0 drivers/most/most_usb.c:959 usb_probe_interface+0x5a0/0xaf0 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x2aa/0xc70 drivers/base/dd.c:639 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:785 driver_probe_device+0x4f/0x420 drivers/base/dd.c:815 __device_attach_driver+0x2c6/0x510 drivers/base/dd.c:943 bus_for_each_drv+0x175/0x200 drivers/base/bus.c:429 __device_attach+0x29b/0x460 drivers/base/dd.c:1015 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489 device_add+0xa00/0xfb0 drivers/base/core.c:3697 usb_set_configuration+0x1991/0x1fd0 drivers/usb/core/message.c:2165 usb_generic_driver_probe+0x89/0x150 drivers/usb/core/generic.c:238 usb_probe_device+0x139/0x270 drivers/usb/core/driver.c:293 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x2aa/0xc70 drivers/base/dd.c:639 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:785 driver_probe_device+0x4f/0x420 drivers/base/dd.c:815 __device_attach_driver+0x2c6/0x510 drivers/base/dd.c:943 bus_for_each_drv+0x175/0x200 drivers/base/bus.c:429 __device_attach+0x29b/0x460 drivers/base/dd.c:1015 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489 device_add+0xa00/0xfb0 drivers/base/core.c:3697 usb_new_device+0xd4d/0x1620 drivers/usb/core/hub.c:2659 hub_port_connect drivers/usb/core/hub.c:5517 [inline] hub_port_connect_change drivers/usb/core/hub.c:5657 [inline] port_event drivers/usb/core/hub.c:5817 [inline] hub_event+0x2d5e/0x54e0 drivers/usb/core/hub.c:5899 process_one_work+0x898/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Freed by task 4311: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook+0x131/0x1a0 mm/slub.c:1750 slab_free mm/slub.c:3661 [inline] __kmem_cache_free+0xb6/0x1f0 mm/slub.c:3674 device_release+0x92/0x1c0 drivers/base/core.c:-1 kobject_cleanup lib/kobject.c:681 [inline] kobject_release lib/kobject.c:712 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x21d/0x460 lib/kobject.c:729 hdm_disconnect+0xef/0x1c0 drivers/most/most_usb.c:1123 usb_unbind_interface+0x1ee/0x860 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:550 [inline] __device_release_driver drivers/base/dd.c:1260 [inline] device_release_driver_internal+0x522/0x850 drivers/base/dd.c:1286 bus_remove_device+0x2e2/0x400 drivers/base/bus.c:531 device_del+0x628/0xa70 drivers/base/core.c:3885 usb_disable_device+0x3e2/0x890 drivers/usb/core/message.c:1414 usb_disconnect+0x348/0x8a0 drivers/usb/core/hub.c:2314 hub_port_connect drivers/usb/core/hub.c:5361 [inline] hub_port_connect_change drivers/usb/core/hub.c:5657 [inline] port_event drivers/usb/core/hub.c:5817 [inline] hub_event+0x1e24/0x54e0 drivers/usb/core/hub.c:5899 process_one_work+0x898/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486 kvfree_call_rcu+0x108/0x870 kernel/rcu/tree.c:3405 device_release+0x92/0x1c0 drivers/base/core.c:-1 kobject_cleanup lib/kobject.c:681 [inline] kobject_release lib/kobject.c:712 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x21d/0x460 lib/kobject.c:729 siw_newlink+0xa0a/0xe60 drivers/infiniband/sw/siw/siw_main.c:515 nldev_newlink+0x48b/0x560 drivers/infiniband/core/nldev.c:1719 rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:-1 [inline] rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline] rdma_nl_rcv+0x6a9/0x990 drivers/infiniband/core/netlink.c:259 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x74d/0x8d0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x89e/0xbc0 net/netlink/af_netlink.c:1872 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] ____sys_sendmsg+0x59b/0x970 net/socket.c:2519 ___sys_sendmsg+0x21c/0x290 net/socket.c:2573 __sys_sendmsg net/socket.c:2602 [inline] __do_sys_sendmsg net/socket.c:2611 [inline] __se_sys_sendmsg+0x19e/0x270 net/socket.c:2609 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff88807c458000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 6296 bytes inside of 8192-byte region [ffff88807c458000, ffff88807c45a000) The buggy address belongs to the physical page: page:ffffea0001f11600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7c458 head:ffffea0001f11600 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0001f64000 dead000000000002 ffff888017442280 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 11819, tgid 11817 (syz.0.2064), ts 965280101517, free_ts 964825082962 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2532 prep_new_page mm/page_alloc.c:2539 [inline] get_page_from_freelist+0x1a26/0x1ac0 mm/page_alloc.c:4328 __alloc_pages+0x1df/0x4e0 mm/page_alloc.c:5614 alloc_slab_page+0x5d/0x160 mm/slub.c:1794 allocate_slab mm/slub.c:1939 [inline] new_slab+0x87/0x2c0 mm/slub.c:1992 ___slab_alloc+0xbc6/0x1220 mm/slub.c:3180 __slab_alloc mm/slub.c:3279 [inline] slab_alloc_node mm/slub.c:3364 [inline] __kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3437 kmalloc_trace+0x26/0xe0 mm/slab_common.c:1026 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] ppp_asynctty_open+0x91/0x560 drivers/net/ppp/ppp_async.c:165 tty_ldisc_open+0x9d/0x100 drivers/tty/tty_ldisc.c:433 tty_set_ldisc+0x370/0x550 drivers/tty/tty_ldisc.c:564 tty_ioctl+0xa1e/0xba0 drivers/tty/tty_io.c:2712 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1459 [inline] free_pcp_prepare mm/page_alloc.c:1509 [inline] free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3384 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3479 free_slab mm/slub.c:2031 [inline] discard_slab mm/slub.c:2037 [inline] __unfreeze_partials+0x1a5/0x200 mm/slub.c:2586 put_cpu_partial+0x17c/0x250 mm/slub.c:2662 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737 slab_alloc_node mm/slub.c:3398 [inline] slab_alloc mm/slub.c:3406 [inline] __kmem_cache_alloc_lru mm/slub.c:3413 [inline] kmem_cache_alloc+0x123/0x2f0 mm/slub.c:3422 vm_area_dup+0x23/0x1a0 kernel/fork.c:467 dup_mmap kernel/fork.c:646 [inline] dup_mm kernel/fork.c:1541 [inline] copy_mm+0xa7e/0x15c0 kernel/fork.c:1590 copy_process+0x1953/0x4020 kernel/fork.c:2351 kernel_clone+0x225/0x8b0 kernel/fork.c:2757 __do_sys_clone kernel/fork.c:2898 [inline] __se_sys_clone kernel/fork.c:2882 [inline] __x64_sys_clone+0x17c/0x1d0 kernel/fork.c:2882 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff88807c459780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807c459800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807c459880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807c459900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807c459980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================