================================================================== BUG: KASAN: slab-use-after-free in instrument_atomic_read include/linux/instrumented.h:68 [inline] BUG: KASAN: slab-use-after-free in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] BUG: KASAN: slab-use-after-free in snd_usbmidi_error_timer+0x15d/0x660 sound/usb/midi.c:355 Read of size 4 at addr ffff88814d52d910 by task udevd/5229 CPU: 0 UID: 0 PID: 5229 Comm: udevd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x2b0/0x2c0 mm/kasan/generic.c:189 instrument_atomic_read include/linux/instrumented.h:68 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] snd_usbmidi_error_timer+0x15d/0x660 sound/usb/midi.c:355 call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers kernel/time/timer.c:2372 [inline] __run_timer_base+0x61a/0x860 kernel/time/timer.c:2384 run_timer_base kernel/time/timer.c:2393 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403 handle_softirqs+0x286/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:rcu_lock_acquire include/linux/rcupdate.h:331 [inline] RIP: 0010:rcu_read_lock include/linux/rcupdate.h:841 [inline] RIP: 0010:class_rcu_constructor include/linux/rcupdate.h:1155 [inline] RIP: 0010:unwind_next_frame+0xa5/0x2390 arch/x86/kernel/unwind_orc.c:479 Code: de 1b 00 00 41 8b 06 85 c0 0f 84 32 02 00 00 89 84 24 84 00 00 00 4c 89 bc 24 90 00 00 00 e8 f2 57 34 00 4c 8d 3d 00 00 00 00 <48> c7 c7 e0 a0 13 8e 31 f6 31 d2 b9 02 00 00 00 45 31 c0 45 31 c9 RSP: 0018:ffffc9000441f8b8 EFLAGS: 00000283 RAX: 0000000000000001 RBX: ffffffff82348839 RCX: dffffc0000000000 RDX: dffffc0000000000 RSI: ffffffff82348839 RDI: ffffc9000441f988 RBP: dffffc0000000000 R08: ffffc9000441fa50 R09: 0000000000000005 R10: dffffc0000000000 R11: ffffffff81ac3b00 R12: 1ffff92000883f31 R13: ffffc9000441f9c0 R14: ffffc9000441f988 R15: ffffffff8172c195 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:243 [inline] __kasan_slab_free+0x5b/0x80 mm/kasan/common.c:275 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2422 [inline] slab_free mm/slub.c:4695 [inline] kmem_cache_free+0x18f/0x400 mm/slub.c:4797 file_free fs/file_table.c:71 [inline] __fput+0x6c2/0xa70 fs/file_table.c:481 fput_close_sync+0x119/0x200 fs/file_table.c:573 __do_sys_close fs/open.c:1587 [inline] __se_sys_close fs/open.c:1572 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1572 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd5ee915a67 Code: 44 00 00 48 83 ec 10 48 63 ff 45 31 c9 45 31 c0 6a 01 31 c9 e8 ca 19 f9 ff 48 83 c4 18 c3 0f 1f 44 00 00 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 8b 15 61 b3 0d 00 f7 d8 64 89 02 b8 RSP: 002b:00007fffbc2010c8 EFLAGS: 00000206 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 000055e2437dd680 RCX: 00007fd5ee915a67 RDX: 0000000000009771 RSI: 00007fd5ee9f1b20 RDI: 000000000000000e RBP: 000055e24392cff0 R08: 0000000000001730 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000206 R12: 000055e2437b77b0 R13: 00000000000000fe R14: 000055e22ea46be0 R15: 00007fffbc201380 Allocated by task 5999: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:388 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:405 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4376 [inline] __kmalloc_noprof+0x27a/0x4f0 mm/slub.c:4388 kmalloc_noprof include/linux/slab.h:909 [inline] usb_alloc_urb+0x46/0x150 drivers/usb/core/urb.c:75 snd_usbmidi_in_endpoint_create+0xb4/0xa30 sound/usb/midi.c:1348 snd_usbmidi_create_endpoints_midiman sound/usb/midi.c:2363 [inline] __snd_usbmidi_create+0x2223/0x2a70 sound/usb/midi.c:2646 snd_usb_midi_v2_create+0x43e6/0x4660 sound/usb/midi2.c:1178 usb_audio_probe+0xb78/0x1e10 sound/usb/card.c:976 usb_probe_interface+0x668/0xc30 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x26d/0x9e0 drivers/base/dd.c:659 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:801 driver_probe_device+0x4f/0x430 drivers/base/dd.c:831 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:959 bus_for_each_drv+0x251/0x2e0 drivers/base/bus.c:462 __device_attach+0x2b8/0x400 drivers/base/dd.c:1031 bus_probe_device+0x185/0x260 drivers/base/bus.c:537 device_add+0x7b6/0xb50 drivers/base/core.c:3689 usb_set_configuration+0x1a87/0x20e0 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250 usb_probe_device+0x1c4/0x390 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x26d/0x9e0 drivers/base/dd.c:659 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:801 driver_probe_device+0x4f/0x430 drivers/base/dd.c:831 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:959 bus_for_each_drv+0x251/0x2e0 drivers/base/bus.c:462 __device_attach+0x2b8/0x400 drivers/base/dd.c:1031 bus_probe_device+0x185/0x260 drivers/base/bus.c:537 device_add+0x7b6/0xb50 drivers/base/core.c:3689 usb_new_device+0xa39/0x16f0 drivers/usb/core/hub.c:2694 hub_port_connect drivers/usb/core/hub.c:5566 [inline] hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] port_event drivers/usb/core/hub.c:5870 [inline] hub_event+0x2958/0x4a20 drivers/usb/core/hub.c:5952 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the object at ffff88814d52d900 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 16 bytes inside of freed 192-byte region [ffff88814d52d900, ffff88814d52d9c0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x14d52d ksm flags: 0x57ff00000000000(node=1|zone=2|lastcpupid=0x7ff) page_type: f5(slab) raw: 057ff00000000000 ffff88801a4413c0 ffffea000533a300 dead000000000003 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 1, tgid 1 (swapper/0), ts 24659201465, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:2492 [inline] allocate_slab+0x8a/0x370 mm/slub.c:2660 new_slab mm/slub.c:2714 [inline] ___slab_alloc+0xbeb/0x1420 mm/slub.c:3901 __slab_alloc mm/slub.c:3992 [inline] __slab_alloc_node mm/slub.c:4067 [inline] slab_alloc_node mm/slub.c:4228 [inline] __do_kmalloc_node mm/slub.c:4375 [inline] __kmalloc_node_track_caller_noprof+0x2f8/0x4e0 mm/slub.c:4395 __do_krealloc mm/slub.c:4957 [inline] krealloc_noprof+0x124/0x340 mm/slub.c:5010 add_sysfs_param+0xc9/0xa20 kernel/params.c:655 kernel_add_sysfs_param+0x7f/0xe0 kernel/params.c:812 param_sysfs_builtin+0x18a/0x230 kernel/params.c:851 param_sysfs_builtin_init+0x23/0x30 kernel/params.c:987 do_one_initcall+0x236/0x820 init/main.c:1269 do_initcall_level+0x104/0x190 init/main.c:1331 do_initcalls+0x59/0xa0 init/main.c:1347 kernel_init_freeable+0x334/0x4b0 init/main.c:1579 page_owner free stack trace missing Memory state around the buggy address: ffff88814d52d800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88814d52d880: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88814d52d900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88814d52d980: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88814d52da00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess): 0: de 1b ficomps (%rbx) 2: 00 00 add %al,(%rax) 4: 41 8b 06 mov (%r14),%eax 7: 85 c0 test %eax,%eax 9: 0f 84 32 02 00 00 je 0x241 f: 89 84 24 84 00 00 00 mov %eax,0x84(%rsp) 16: 4c 89 bc 24 90 00 00 mov %r15,0x90(%rsp) 1d: 00 1e: e8 f2 57 34 00 call 0x345815 23: 4c 8d 3d 00 00 00 00 lea 0x0(%rip),%r15 # 0x2a * 2a: 48 c7 c7 e0 a0 13 8e mov $0xffffffff8e13a0e0,%rdi <-- trapping instruction 31: 31 f6 xor %esi,%esi 33: 31 d2 xor %edx,%edx 35: b9 02 00 00 00 mov $0x2,%ecx 3a: 45 31 c0 xor %r8d,%r8d 3d: 45 31 c9 xor %r9d,%r9d