================================================================== BUG: KASAN: use-after-free in snd_usbmidi_error_timer+0x5fe/0x660 sound/usb/midi.c:352 Read of size 1 at addr ffff888060e9b143 by task kworker/0:0/7 CPU: 0 PID: 7 Comm: kworker/0:0 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: usb_hub_wq hub_event Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 print_address_description+0x60/0x2d0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0xdf/0x130 mm/kasan/report.c:451 snd_usbmidi_error_timer+0x5fe/0x660 sound/usb/midi.c:352 call_timer_fn+0x16c/0x530 kernel/time/timer.c:1451 expire_timers kernel/time/timer.c:1496 [inline] __run_timers+0x525/0x7c0 kernel/time/timer.c:1767 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780 handle_softirqs+0x328/0x820 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:console_unlock+0xd90/0x1200 kernel/printk/printk.c:2749 Code: 00 48 83 7c 24 28 00 75 19 e8 4c 94 18 00 eb 18 e8 45 94 18 00 e8 80 af 42 08 48 83 7c 24 28 00 74 e7 e8 33 94 18 00 fb 31 ff <89> de e8 89 97 18 00 85 db 0f 94 c0 22 44 24 17 3c 01 75 1f e8 17 RSP: 0018:ffffc90000cc6660 EFLAGS: 00000246 RAX: ffffffff815f37dd RBX: 0000000000000000 RCX: 0000000000100000 RDX: ffffc9001495a000 RSI: 000000000007cbbe RDI: 0000000000000000 RBP: ffffc90000cc68d0 R08: dffffc0000000000 R09: fffffbfff1ff5419 R10: fffffbfff1ff5419 R11: 1ffffffff1ff5418 R12: 1ffffffff194c7e9 R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffffffff194c7e2 vprintk_emit+0xc0/0x150 kernel/printk/printk.c:2274 __warn_printk+0xda/0x120 kernel/panic.c:721 debug_print_object lib/debugobjects.c:518 [inline] __debug_check_no_obj_freed lib/debugobjects.c:973 [inline] debug_check_no_obj_freed+0x43c/0x530 lib/debugobjects.c:1003 slab_free_hook mm/slub.c:1685 [inline] slab_free_freelist_hook+0x8b/0x170 mm/slub.c:1736 slab_free mm/slub.c:3504 [inline] kfree+0xef/0x2a0 mm/slub.c:4564 snd_rawmidi_free+0x3b7/0x3e0 sound/core/rawmidi.c:1844 snd_rawmidi_dev_free+0x34/0x40 sound/core/rawmidi.c:1853 __snd_device_free+0x1cd/0x2e0 sound/core/device.c:76 snd_device_free_all+0xcb/0x180 sound/core/device.c:233 snd_card_do_free sound/core/init.c:588 [inline] release_card_device+0x6d/0x1f0 sound/core/init.c:145 device_release+0x92/0x1c0 drivers/base/core.c:-1 kobject_cleanup lib/kobject.c:713 [inline] kobject_release lib/kobject.c:744 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x21d/0x460 lib/kobject.c:761 snd_card_free_when_closed sound/core/init.c:620 [inline] snd_card_free+0x123/0x190 sound/core/init.c:653 usb_audio_probe+0x187f/0x1d50 sound/usb/card.c:939 usb_probe_interface+0x5a0/0xaf0 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x284/0xc80 drivers/base/dd.c:595 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:755 driver_probe_device+0x4f/0x420 drivers/base/dd.c:785 __device_attach_driver+0x2b0/0x500 drivers/base/dd.c:907 bus_for_each_drv+0x175/0x200 drivers/base/bus.c:429 __device_attach+0x29b/0x460 drivers/base/dd.c:979 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489 device_add+0xa00/0xfb0 drivers/base/core.c:3412 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+0x284/0xc80 drivers/base/dd.c:595 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:755 driver_probe_device+0x4f/0x420 drivers/base/dd.c:785 __device_attach_driver+0x2b0/0x500 drivers/base/dd.c:907 bus_for_each_drv+0x175/0x200 drivers/base/bus.c:429 __device_attach+0x29b/0x460 drivers/base/dd.c:979 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489 device_add+0xa00/0xfb0 drivers/base/core.c:3412 usb_new_device+0xd53/0x1640 drivers/usb/core/hub.c:2632 hub_port_connect drivers/usb/core/hub.c:5497 [inline] hub_port_connect_change drivers/usb/core/hub.c:5637 [inline] port_event drivers/usb/core/hub.c:5799 [inline] hub_event+0x2dd9/0x5560 drivers/usb/core/hub.c:5881 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Allocated by task 7: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc+0xb5/0xf0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:607 [inline] kzalloc include/linux/slab.h:738 [inline] snd_usbmidi_in_endpoint_create+0x7e/0xa20 sound/usb/midi.c:1342 snd_usbmidi_create_endpoints sound/usb/midi.c:1937 [inline] __snd_usbmidi_create+0x16f8/0x2f90 sound/usb/midi.c:2659 snd_usb_create_quirk sound/usb/quirks.c:577 [inline] create_composite_quirk+0x1ec/0x4e0 sound/usb/quirks.c:48 usb_audio_probe+0xb72/0x1d50 sound/usb/card.c:885 usb_probe_interface+0x5a0/0xaf0 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x284/0xc80 drivers/base/dd.c:595 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:755 driver_probe_device+0x4f/0x420 drivers/base/dd.c:785 __device_attach_driver+0x2b0/0x500 drivers/base/dd.c:907 bus_for_each_drv+0x175/0x200 drivers/base/bus.c:429 __device_attach+0x29b/0x460 drivers/base/dd.c:979 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489 device_add+0xa00/0xfb0 drivers/base/core.c:3412 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+0x284/0xc80 drivers/base/dd.c:595 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:755 driver_probe_device+0x4f/0x420 drivers/base/dd.c:785 __device_attach_driver+0x2b0/0x500 drivers/base/dd.c:907 bus_for_each_drv+0x175/0x200 drivers/base/bus.c:429 __device_attach+0x29b/0x460 drivers/base/dd.c:979 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489 device_add+0xa00/0xfb0 drivers/base/core.c:3412 usb_new_device+0xd53/0x1640 drivers/usb/core/hub.c:2632 hub_port_connect drivers/usb/core/hub.c:5497 [inline] hub_port_connect_change drivers/usb/core/hub.c:5637 [inline] port_event drivers/usb/core/hub.c:5799 [inline] hub_event+0x2dd9/0x5560 drivers/usb/core/hub.c:5881 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Freed by task 7: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1710 [inline] slab_free_freelist_hook+0xea/0x170 mm/slub.c:1736 slab_free mm/slub.c:3504 [inline] kfree+0xef/0x2a0 mm/slub.c:4564 snd_usbmidi_free sound/usb/midi.c:1530 [inline] snd_usbmidi_rawmidi_free+0xaa/0x150 sound/usb/midi.c:1590 snd_rawmidi_free+0x3b7/0x3e0 sound/core/rawmidi.c:1844 snd_rawmidi_dev_free+0x34/0x40 sound/core/rawmidi.c:1853 __snd_device_free+0x1cd/0x2e0 sound/core/device.c:76 snd_device_free_all+0xcb/0x180 sound/core/device.c:233 snd_card_do_free sound/core/init.c:588 [inline] release_card_device+0x6d/0x1f0 sound/core/init.c:145 device_release+0x92/0x1c0 drivers/base/core.c:-1 kobject_cleanup lib/kobject.c:713 [inline] kobject_release lib/kobject.c:744 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x21d/0x460 lib/kobject.c:761 snd_card_free_when_closed sound/core/init.c:620 [inline] snd_card_free+0x123/0x190 sound/core/init.c:653 usb_audio_probe+0x187f/0x1d50 sound/usb/card.c:939 usb_probe_interface+0x5a0/0xaf0 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x284/0xc80 drivers/base/dd.c:595 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:755 driver_probe_device+0x4f/0x420 drivers/base/dd.c:785 __device_attach_driver+0x2b0/0x500 drivers/base/dd.c:907 bus_for_each_drv+0x175/0x200 drivers/base/bus.c:429 __device_attach+0x29b/0x460 drivers/base/dd.c:979 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489 device_add+0xa00/0xfb0 drivers/base/core.c:3412 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+0x284/0xc80 drivers/base/dd.c:595 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:755 driver_probe_device+0x4f/0x420 drivers/base/dd.c:785 __device_attach_driver+0x2b0/0x500 drivers/base/dd.c:907 bus_for_each_drv+0x175/0x200 drivers/base/bus.c:429 __device_attach+0x29b/0x460 drivers/base/dd.c:979 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489 device_add+0xa00/0xfb0 drivers/base/core.c:3412 usb_new_device+0xd53/0x1640 drivers/usb/core/hub.c:2632 hub_port_connect drivers/usb/core/hub.c:5497 [inline] hub_port_connect_change drivers/usb/core/hub.c:5637 [inline] port_event drivers/usb/core/hub.c:5799 [inline] hub_event+0x2dd9/0x5560 drivers/usb/core/hub.c:5881 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 The buggy address belongs to the object at ffff888060e9b000 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 323 bytes inside of 512-byte region [ffff888060e9b000, ffff888060e9b200) The buggy address belongs to the page: page:ffffea000183a600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x60e98 head:ffffea000183a600 order:2 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 0000000100000001 ffff888016841c80 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4180, ts 68136243613, free_ts 68134446984 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x1b77/0x1c60 mm/page_alloc.c:4192 __alloc_pages+0x1e1/0x470 mm/page_alloc.c:5487 alloc_slab_page mm/slub.c:1780 [inline] allocate_slab mm/slub.c:1917 [inline] new_slab+0xc0/0x4b0 mm/slub.c:1980 ___slab_alloc+0x81e/0xdf0 mm/slub.c:3013 __slab_alloc mm/slub.c:3100 [inline] slab_alloc_node mm/slub.c:3191 [inline] __kmalloc_node_track_caller+0x1fc/0x3a0 mm/slub.c:4963 kmalloc_reserve net/core/skbuff.c:356 [inline] __alloc_skb+0x22c/0x750 net/core/skbuff.c:427 alloc_skb include/linux/skbuff.h:1162 [inline] nlmsg_new include/net/netlink.h:953 [inline] inet_netconf_notify_devconf+0x16f/0x230 net/ipv4/devinet.c:2121 __devinet_sysctl_register+0x321/0x380 net/ipv4/devinet.c:2609 devinet_sysctl_register+0x17c/0x1f0 net/ipv4/devinet.c:2643 inetdev_init+0x28c/0x4d0 net/ipv4/devinet.c:277 inetdev_event+0x280/0x1360 net/ipv4/devinet.c:1543 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391 call_netdevice_notifiers_extack net/core/dev.c:2061 [inline] call_netdevice_notifiers net/core/dev.c:2075 [inline] register_netdevice+0x1275/0x16b0 net/core/dev.c:10428 ip6gre_newlink_common+0x39a/0x530 net/ipv6/ip6_gre.c:2005 ip6gre_newlink+0x1d4/0x530 net/ipv6/ip6_gre.c:2036 __rtnl_newlink net/core/rtnetlink.c:3526 [inline] rtnl_newlink+0x114c/0x17d0 net/core/rtnetlink.c:3574 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317 free_unref_page+0x94/0x280 mm/page_alloc.c:3396 stack_depot_save+0x418/0x440 lib/stackdepot.c:335 kasan_save_stack mm/kasan/common.c:40 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0xb3/0xd0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3225 [inline] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc+0x100/0x290 mm/slub.c:3238 radix_tree_node_alloc+0x197/0x3a0 lib/radix-tree.c:251 idr_get_free+0x2af/0xa60 lib/radix-tree.c:1504 idr_alloc_u32 lib/idr.c:46 [inline] idr_alloc_cyclic+0x19e/0x530 lib/idr.c:125 __kernfs_new_node+0x120/0x680 fs/kernfs/dir.c:599 kernfs_new_node+0x148/0x250 fs/kernfs/dir.c:669 kernfs_create_link+0xa3/0x200 fs/kernfs/symlink.c:39 sysfs_do_create_link_sd+0x83/0x110 fs/sysfs/symlink.c:44 device_add_class_symlinks drivers/base/core.c:3154 [inline] device_add+0x7ed/0xfb0 drivers/base/core.c:3360 netdev_register_kobject+0x176/0x310 net/core/net-sysfs.c:2014 register_netdevice+0x1019/0x16b0 net/core/dev.c:10397 Memory state around the buggy address: ffff888060e9b000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888060e9b080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888060e9b100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888060e9b180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888060e9b200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: 00 48 83 add %cl,-0x7d(%rax) 3: 7c 24 jl 0x29 5: 28 00 sub %al,(%rax) 7: 75 19 jne 0x22 9: e8 4c 94 18 00 call 0x18945a e: eb 18 jmp 0x28 10: e8 45 94 18 00 call 0x18945a 15: e8 80 af 42 08 call 0x842af9a 1a: 48 83 7c 24 28 00 cmpq $0x0,0x28(%rsp) 20: 74 e7 je 0x9 22: e8 33 94 18 00 call 0x18945a 27: fb sti 28: 31 ff xor %edi,%edi * 2a: 89 de mov %ebx,%esi <-- trapping instruction 2c: e8 89 97 18 00 call 0x1897ba 31: 85 db test %ebx,%ebx 33: 0f 94 c0 sete %al 36: 22 44 24 17 and 0x17(%rsp),%al 3a: 3c 01 cmp $0x1,%al 3c: 75 1f jne 0x5d 3e: e8 .byte 0xe8 3f: 17 (bad)