================================================================== 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+0x52d/0x670 sound/usb/midi2.c:941 Write of size 8 at addr ffff888054d7a350 by task syz.1.67/6101 CPU: 1 UID: 0 PID: 6101 Comm: syz.1.67 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595 free_all_midi2_umps sound/usb/midi2.c:689 [inline] snd_usb_midi_v2_free+0x52d/0x670 sound/usb/midi2.c:941 snd_usb_midi_v2_free_all+0x85/0xe0 sound/usb/midi2.c:1240 snd_usb_audio_free+0x4e/0x120 sound/usb/card.c:608 snd_card_do_free sound/core/init.c:594 [inline] release_card_device+0xb2/0x1a0 sound/core/init.c:153 device_release+0xd2/0x270 drivers/base/core.c:2636 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1f7/0x640 lib/kobject.c:737 put_device+0x1f/0x30 drivers/base/core.c:3880 snd_card_free_when_closed sound/core/init.c:626 [inline] snd_card_free_when_closed+0x2b/0x40 sound/core/init.c:620 usb_audio_disconnect+0x210/0x680 sound/usb/card.c:1159 usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:618 [inline] device_remove+0x12a/0x180 drivers/base/dd.c:610 __device_release_driver drivers/base/dd.c:1349 [inline] device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1372 usb_driver_release_interface+0x10e/0x190 drivers/usb/core/driver.c:640 proc_ioctl+0x5cd/0x6f0 drivers/usb/core/devio.c:2359 proc_ioctl_default drivers/usb/core/devio.c:2402 [inline] usbdev_do_ioctl drivers/usb/core/devio.c:2766 [inline] usbdev_ioctl+0x1017/0x3aa0 drivers/usb/core/devio.c:2826 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f693739e019 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f6938198028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f6937626090 RCX: 00007f693739e019 RDX: 0000200000000200 RSI: 00000000c0105512 RDI: 0000000000000004 RBP: 00007f693743500c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6937626128 R14: 00007f6937626090 R15: 00007fff763a3988 Allocated by task 5798: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x2e5/0x6c0 mm/slub.c:5489 _kmalloc_noprof include/linux/slab.h:988 [inline] _kzalloc_noprof include/linux/slab.h:1309 [inline] snd_ump_endpoint_new+0x93/0x470 sound/core/ump.c:169 create_midi2_ump+0x2dd/0x920 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+0x11fa/0x4070 sound/usb/midi2.c:1129 snd_usb_create_stream.isra.0+0x386/0x4d0 sound/usb/card.c:290 snd_usb_create_streams sound/usb/card.c:392 [inline] usb_audio_probe+0xf05/0x3b10 sound/usb/card.c:1031 usb_probe_interface+0x303/0x8f0 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:628 [inline] really_probe+0x241/0xa60 drivers/base/dd.c:706 __driver_probe_device+0x20e/0x450 drivers/base/dd.c:868 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898 __device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153 bus_probe_device+0x64/0x160 drivers/base/bus.c:620 device_add+0x121d/0x1970 drivers/base/core.c:3772 usb_set_configuration+0xd97/0x1c60 drivers/usb/core/message.c:2268 usb_generic_driver_probe+0xa1/0xe0 drivers/usb/core/generic.c:250 usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:628 [inline] really_probe+0x241/0xa60 drivers/base/dd.c:706 __driver_probe_device+0x20e/0x450 drivers/base/dd.c:868 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898 __device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153 bus_probe_device+0x64/0x160 drivers/base/bus.c:620 device_add+0x121d/0x1970 drivers/base/core.c:3772 usb_new_device.cold+0x685/0x115c drivers/usb/core/hub.c:2695 hub_port_connect drivers/usb/core/hub.c:5567 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x30a3/0x4a60 drivers/usb/core/hub.c:5953 process_one_work+0xa23/0x1940 kernel/workqueue.c:3322 process_scheduled_works kernel/workqueue.c:3405 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Freed by task 6101: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2677 [inline] slab_free mm/slub.c:6377 [inline] kfree+0x22b/0x6c0 mm/slub.c:6692 snd_rawmidi_free sound/core/rawmidi.c:1923 [inline] snd_rawmidi_dev_free+0x3e/0x60 sound/core/rawmidi.c:1945 __snd_device_free+0x1a3/0x300 sound/core/device.c:76 snd_device_free_all+0xf3/0x220 sound/core/device.c:233 snd_card_do_free sound/core/init.c:592 [inline] release_card_device+0x77/0x1a0 sound/core/init.c:153 device_release+0xd2/0x270 drivers/base/core.c:2636 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1f7/0x640 lib/kobject.c:737 put_device+0x1f/0x30 drivers/base/core.c:3880 snd_card_free_when_closed sound/core/init.c:626 [inline] snd_card_free_when_closed+0x2b/0x40 sound/core/init.c:620 usb_audio_disconnect+0x210/0x680 sound/usb/card.c:1159 usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:618 [inline] device_remove+0x12a/0x180 drivers/base/dd.c:610 __device_release_driver drivers/base/dd.c:1349 [inline] device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1372 usb_driver_release_interface+0x10e/0x190 drivers/usb/core/driver.c:640 proc_ioctl+0x5cd/0x6f0 drivers/usb/core/devio.c:2359 proc_ioctl_default drivers/usb/core/devio.c:2402 [inline] usbdev_do_ioctl drivers/usb/core/devio.c:2766 [inline] usbdev_ioctl+0x1017/0x3aa0 drivers/usb/core/devio.c:2826 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888054d7a000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 848 bytes inside of freed 4096-byte region [ffff888054d7a000, ffff888054d7b000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x54d78 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 ffff88813fe28140 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800040004 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88813fe28140 dead000000000100 dead000000000122 head: 0000000000000000 0000000800040004 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 5620, tgid 5620 (syz-executor), ts 72583840072, free_ts 17582736686 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859 prep_new_page mm/page_alloc.c:1867 [inline] get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304 alloc_slab_page mm/slub.c:3266 [inline] allocate_slab mm/slub.c:3380 [inline] new_slab+0xa2/0x640 mm/slub.c:3426 refill_objects+0xe3/0x410 mm/slub.c:7310 refill_sheaf mm/slub.c:2804 [inline] __pcs_replace_empty_main+0x376/0x680 mm/slub.c:4675 alloc_from_pcs mm/slub.c:4773 [inline] slab_alloc_node mm/slub.c:4905 [inline] __do_kmalloc_node mm/slub.c:5333 [inline] __kmalloc_noprof+0x66d/0x820 mm/slub.c:5359 _kmalloc_noprof include/linux/slab.h:992 [inline] tomoyo_realpath_from_path+0xb6/0x690 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_number_perm+0x23c/0x580 security/tomoyo/file.c:728 security_file_ioctl+0xd3/0x230 security/security.c:2512 __do_sys_ioctl fs/ioctl.c:591 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0xb7/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 1 tgid 1 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1406 [inline] free_pages_prepare+0x586/0xd80 mm/page_alloc.c:1451 __free_contig_range_common+0x14f/0x250 mm/page_alloc.c:6897 debug_vm_pgtable_free_huge_page mm/debug_vm_pgtable.c:980 [inline] destroy_args+0xa8/0x7a0 mm/debug_vm_pgtable.c:993 debug_vm_pgtable+0x1d69/0x3490 mm/debug_vm_pgtable.c:1368 do_one_initcall+0x11d/0x700 init/main.c:1347 do_initcall_level init/main.c:1409 [inline] do_initcalls init/main.c:1425 [inline] do_basic_setup init/main.c:1445 [inline] kernel_init_freeable+0x6ea/0x7b0 init/main.c:1658 kernel_init+0x1f/0x1e0 init/main.c:1548 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff888054d7a200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888054d7a280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888054d7a300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888054d7a380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888054d7a400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================