================================================================== BUG: KASAN: slab-use-after-free in free_all_midi2_umps sound/usb/midi2.c:689 [inline] BUG: KASAN: slab-use-after-free in snd_usb_midi_v2_free+0x602/0x7b0 sound/usb/midi2.c:941 Write of size 8 at addr ffff88802b4fa350 by task kworker/1:4/5736 CPU: 1 UID: 0 PID: 5736 Comm: kworker/1:4 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Workqueue: usb_hub_wq hub_event Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 free_all_midi2_umps sound/usb/midi2.c:689 [inline] snd_usb_midi_v2_free+0x602/0x7b0 sound/usb/midi2.c:941 snd_usb_midi_v2_free_all+0x67/0x90 sound/usb/midi2.c:1240 snd_usb_audio_free+0x4c/0x100 sound/usb/card.c:608 snd_card_do_free sound/core/init.c:596 [inline] release_card_device+0x113/0x240 sound/core/init.c:153 device_release+0xc4/0x1f0 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+0x222/0x550 lib/kobject.c:737 usb_unbind_interface+0x295/0x9f0 drivers/usb/core/driver.c:461 device_remove drivers/base/dd.c:618 [inline] __device_release_driver drivers/base/dd.c:1349 [inline] device_release_driver_internal+0x4f5/0x880 drivers/base/dd.c:1372 bus_remove_device+0x444/0x560 drivers/base/bus.c:664 device_del+0x524/0x8f0 drivers/base/core.c:3965 usb_disable_device+0x3d4/0x8d0 drivers/usb/core/message.c:1478 usb_disconnect+0x346/0x9a0 drivers/usb/core/hub.c:2350 hub_port_connect drivers/usb/core/hub.c:5420 [inline] hub_port_connect_change drivers/usb/core/hub.c:5720 [inline] port_event drivers/usb/core/hub.c:5884 [inline] hub_event+0x1bbb/0x4d30 drivers/usb/core/hub.c:5966 process_one_work kernel/workqueue.c:3375 [inline] process_scheduled_works+0xc4e/0x1630 kernel/workqueue.c:3458 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3539 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 5749: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x31d/0x600 mm/slub.c:5563 _kmalloc_noprof include/linux/slab.h:991 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] snd_ump_endpoint_new+0x7d/0x3d0 sound/core/ump.c:169 create_midi2_ump+0x314/0x7b0 sound/usb/midi2.c:717 find_matching_ep_partner sound/usb/midi2.c:781 [inline] parse_midi_2_0 sound/usb/midi2.c:973 [inline] snd_usb_midi_v2_create+0x140d/0x4ac0 sound/usb/midi2.c:1129 snd_usb_create_stream+0x262/0x630 sound/usb/card.c:290 snd_usb_create_streams sound/usb/card.c:392 [inline] usb_audio_probe+0x144c/0x2240 sound/usb/card.c:1065 usb_probe_interface+0x788/0xe50 drivers/usb/core/driver.c:399 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x254/0xae0 drivers/base/dd.c:706 __driver_probe_device+0x1e8/0x360 drivers/base/dd.c:868 driver_probe_device+0x4f/0x240 drivers/base/dd.c:898 __device_attach_driver+0x270/0x410 drivers/base/dd.c:1026 bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500 __device_attach+0x2c4/0x450 drivers/base/dd.c:1098 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1153 bus_probe_device+0x12a/0x220 drivers/base/bus.c:620 device_add+0x7d7/0xb80 drivers/base/core.c:3776 usb_set_configuration+0x1ad8/0x2180 drivers/usb/core/message.c:2268 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250 usb_probe_device+0x1c3/0x3b0 drivers/usb/core/driver.c:293 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x254/0xae0 drivers/base/dd.c:706 __driver_probe_device+0x1e8/0x360 drivers/base/dd.c:868 driver_probe_device+0x4f/0x240 drivers/base/dd.c:898 __device_attach_driver+0x270/0x410 drivers/base/dd.c:1026 bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500 __device_attach+0x2c4/0x450 drivers/base/dd.c:1098 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1153 bus_probe_device+0x12a/0x220 drivers/base/bus.c:620 device_add+0x7d7/0xb80 drivers/base/core.c:3776 usb_new_device+0x9aa/0x1690 drivers/usb/core/hub.c:2708 hub_port_connect drivers/usb/core/hub.c:5580 [inline] hub_port_connect_change drivers/usb/core/hub.c:5720 [inline] port_event drivers/usb/core/hub.c:5884 [inline] hub_event+0x28e8/0x4d30 drivers/usb/core/hub.c:5966 process_one_work kernel/workqueue.c:3375 [inline] process_scheduled_works+0xc4e/0x1630 kernel/workqueue.c:3458 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3539 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Freed by task 5736: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2748 [inline] slab_free mm/slub.c:6499 [inline] kfree+0x1c5/0x650 mm/slub.c:6792 snd_rawmidi_free+0x400/0x420 sound/core/rawmidi.c:1934 snd_rawmidi_dev_free+0x38/0x50 sound/core/rawmidi.c:1943 __snd_device_free sound/core/device.c:76 [inline] snd_device_free_all+0x2c7/0x7a0 sound/core/device.c:233 snd_card_do_free sound/core/init.c:591 [inline] release_card_device+0x77/0x240 sound/core/init.c:153 device_release+0xc4/0x1f0 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+0x222/0x550 lib/kobject.c:737 usb_unbind_interface+0x295/0x9f0 drivers/usb/core/driver.c:461 device_remove drivers/base/dd.c:618 [inline] __device_release_driver drivers/base/dd.c:1349 [inline] device_release_driver_internal+0x4f5/0x880 drivers/base/dd.c:1372 bus_remove_device+0x444/0x560 drivers/base/bus.c:664 device_del+0x524/0x8f0 drivers/base/core.c:3965 usb_disable_device+0x3d4/0x8d0 drivers/usb/core/message.c:1478 usb_disconnect+0x346/0x9a0 drivers/usb/core/hub.c:2350 hub_port_connect drivers/usb/core/hub.c:5420 [inline] hub_port_connect_change drivers/usb/core/hub.c:5720 [inline] port_event drivers/usb/core/hub.c:5884 [inline] hub_event+0x1bbb/0x4d30 drivers/usb/core/hub.c:5966 process_one_work kernel/workqueue.c:3375 [inline] process_scheduled_works+0xc4e/0x1630 kernel/workqueue.c:3458 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3539 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the object at ffff88802b4fa000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 848 bytes inside of freed 4096-byte region [ffff88802b4fa000, ffff88802b4fb000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2b4f8 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801b008140 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000040004 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801b008140 dead000000000100 dead000000000122 head: 0000000000000000 0000000000040004 00000000f5000000 0000000000000000 head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 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 4990, tgid 4990 (udevd), ts 41532662426 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1871 prep_new_page mm/page_alloc.c:1879 [inline] get_page_from_freelist+0x2205/0x2280 mm/page_alloc.c:4001 __alloc_frozen_pages_noprof+0x217/0x5a0 mm/page_alloc.c:5498 alloc_slab_page mm/slub.c:3347 [inline] allocate_slab+0x7d/0x620 mm/slub.c:3462 new_slab mm/slub.c:3513 [inline] refill_objects+0x2d5/0x350 mm/slub.c:7410 refill_sheaf mm/slub.c:2885 [inline] __pcs_replace_empty_main+0x2c4/0x6b0 mm/slub.c:4774 alloc_from_pcs mm/slub.c:4850 [inline] slab_alloc_node mm/slub.c:4984 [inline] __do_kmalloc_node mm/slub.c:5413 [inline] __kmalloc_noprof+0x477/0x710 mm/slub.c:5439 _kmalloc_noprof include/linux/slab.h:995 [inline] tomoyo_realpath_from_path+0xef/0x640 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_number_perm+0x246/0x5f0 security/tomoyo/file.c:728 tomoyo_path_mknod+0x14a/0x1a0 security/tomoyo/tomoyo.c:252 security_path_mknod+0x176/0x370 security/security.c:1417 may_o_create fs/namei.c:4319 [inline] lookup_open+0x626/0x1a40 fs/namei.c:4512 open_last_lookups fs/namei.c:4767 [inline] path_openat+0x677/0x1d60 fs/namei.c:4997 do_file_open+0x23e/0x4a0 fs/namei.c:5029 do_sys_openat2+0x115/0x200 fs/open.c:1417 do_sys_open fs/open.c:1423 [inline] __do_sys_openat fs/open.c:1439 [inline] __se_sys_openat fs/open.c:1434 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1434 page last free pid 4968 tgid 4968 ts 41422167814 stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] __free_pages_prepare mm/page_alloc.c:1418 [inline] __free_frozen_pages+0xc8f/0xd80 mm/page_alloc.c:3020 __slab_free+0x274/0x2c0 mm/slub.c:5815 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4683 [inline] slab_alloc_node mm/slub.c:4996 [inline] __do_kmalloc_node mm/slub.c:5413 [inline] __kmalloc_noprof+0x303/0x710 mm/slub.c:5439 _kmalloc_noprof include/linux/slab.h:995 [inline] tomoyo_add_entry security/tomoyo/common.c:2166 [inline] tomoyo_supervisor+0xc53/0x1560 security/tomoyo/common.c:2238 tomoyo_audit_path_log security/tomoyo/file.c:169 [inline] tomoyo_path_permission+0x262/0x3b0 security/tomoyo/file.c:592 tomoyo_check_open_permission+0x2b2/0x470 security/tomoyo/file.c:782 security_file_open+0xa9/0x240 security/security.c:2739 do_dentry_open+0x4a0/0x1380 fs/open.c:973 vfs_open+0x3b/0x340 fs/open.c:1101 do_open fs/namei.c:4837 [inline] path_openat+0x1443/0x1d60 fs/namei.c:5000 do_file_open+0x23e/0x4a0 fs/namei.c:5029 do_sys_openat2+0x115/0x200 fs/open.c:1417 do_sys_open fs/open.c:1423 [inline] __do_sys_openat fs/open.c:1439 [inline] __se_sys_openat fs/open.c:1434 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1434 Memory state around the buggy address: ffff88802b4fa200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802b4fa280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802b4fa300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802b4fa380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802b4fa400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================