================================================================== BUG: KASAN: use-after-free in __list_del_entry_valid+0xd2/0xf5 lib/list_debug.c:42 Read of size 8 at addr ffff8880860aa0e0 by task syz-executor.4/18429 CPU: 1 PID: 18429 Comm: syz-executor.4 Not tainted 5.1.0-rc3-next-20190408 #20 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:132 __list_del_entry_valid+0xd2/0xf5 lib/list_debug.c:42 __list_del_entry include/linux/list.h:117 [inline] list_del_init include/linux/list.h:176 [inline] snd_timer_process_callbacks+0x7f/0x2f0 sound/core/timer.c:763 snd_timer_interrupt sound/core/timer.c:883 [inline] snd_timer_interrupt+0x578/0xdd0 sound/core/timer.c:804 snd_hrtimer_callback+0x219/0x3e0 sound/core/hrtimer.c:64 __run_hrtimer kernel/time/hrtimer.c:1389 [inline] __hrtimer_run_queues+0x33e/0xde0 kernel/time/hrtimer.c:1451 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1509 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1035 [inline] smp_apic_timer_interrupt+0x120/0x570 arch/x86/kernel/apic/apic.c:1060 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:767 [inline] RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x95/0xe0 kernel/locking/spinlock.c:184 Code: 48 c7 c0 70 9b 92 88 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 39 48 83 3d 22 d5 78 01 00 74 24 48 89 df 57 9d <0f> 1f 44 00 00 bf 01 00 00 00 e8 dc e1 33 fa 65 8b 05 25 27 e8 78 RSP: 0018:ffff888052f9f5a0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff112536e RBX: 0000000000000282 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: 0000000000000006 RDI: 0000000000000282 RBP: ffff888052f9f5b0 R08: ffff88808df48440 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff88805a2399a8 R13: dffffc0000000000 R14: ffff888052f9f730 R15: ffff88805a2399a8 spin_unlock_irqrestore include/linux/spinlock.h:384 [inline] __skb_try_recv_datagram+0x2c4/0x4a0 net/core/datagram.c:274 __skb_recv_datagram+0x1e1/0x250 net/core/datagram.c:305 skb_recv_datagram+0xc8/0x110 net/core/datagram.c:324 raw_recvmsg+0x121/0x850 net/ipv4/raw.c:771 inet_recvmsg+0x13b/0x620 net/ipv4/af_inet.c:834 sock_recvmsg_nosec+0x8c/0xb0 net/socket.c:881 ___sys_recvmsg+0x273/0x5a0 net/socket.c:2422 do_recvmmsg+0x27e/0x7a0 net/socket.c:2535 __sys_recvmmsg+0x259/0x270 net/socket.c:2614 __do_sys_recvmmsg net/socket.c:2637 [inline] __se_sys_recvmmsg net/socket.c:2630 [inline] __x64_sys_recvmmsg+0xe6/0x140 net/socket.c:2630 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4582b9 Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f0b45e44c78 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00000000004582b9 RDX: 00000000006fdaec RSI: 00000000200004c0 RDI: 0000000000000005 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000022 R11: 0000000000000246 R12: 00007f0b45e456d4 R13: 00000000004c4f97 R14: 00000000004d8eb8 R15: 00000000ffffffff Allocated by task 18440: save_stack+0x45/0xd0 mm/kasan/common.c:75 set_track mm/kasan/common.c:87 [inline] __kasan_kmalloc mm/kasan/common.c:497 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:470 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:511 kmem_cache_alloc_trace+0x151/0x760 mm/slab.c:3621 kmalloc include/linux/slab.h:547 [inline] kzalloc include/linux/slab.h:742 [inline] snd_timer_instance_new+0x4f/0x3d0 sound/core/timer.c:109 snd_timer_open+0x8a7/0x1760 sound/core/timer.c:313 snd_seq_timer_open+0x240/0x590 sound/core/seq/seq_timer.c:290 queue_use+0xcb/0x240 sound/core/seq/seq_queue.c:502 snd_seq_queue_alloc+0x2c5/0x4d0 sound/core/seq/seq_queue.c:189 snd_seq_ioctl_create_queue+0xb0/0x330 sound/core/seq/seq_clientmgr.c:1522 snd_seq_ioctl+0x224/0x3e0 sound/core/seq/seq_clientmgr.c:2138 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0xd6e/0x1390 fs/ioctl.c:696 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 18440: save_stack+0x45/0xd0 mm/kasan/common.c:75 set_track mm/kasan/common.c:87 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:459 kasan_slab_free+0xe/0x10 mm/kasan/common.c:467 __cache_free mm/slab.c:3498 [inline] kfree+0xcf/0x230 mm/slab.c:3821 snd_timer_close_locked+0x6fd/0xd60 sound/core/timer.c:405 snd_timer_close+0x2e/0x70 sound/core/timer.c:430 snd_seq_timer_close+0x91/0xd0 sound/core/seq/seq_timer.c:329 queue_delete+0x52/0xb0 sound/core/seq/seq_queue.c:147 snd_seq_queue_client_leave+0x36/0x170 sound/core/seq/seq_queue.c:584 seq_free_client1.part.0+0xf3/0x270 sound/core/seq/seq_clientmgr.c:263 seq_free_client1 sound/core/seq/seq_clientmgr.c:256 [inline] seq_free_client+0x80/0xf0 sound/core/seq/seq_clientmgr.c:285 snd_seq_release+0x55/0xf0 sound/core/seq/seq_clientmgr.c:366 __fput+0x2e5/0x8d0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x14a/0x1c0 kernel/task_work.c:113 get_signal+0x1961/0x1d50 kernel/signal.c:2391 do_signal+0x87/0x1940 arch/x86/kernel/signal.c:816 exit_to_usermode_loop+0x244/0x2c0 arch/x86/entry/common.c:162 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x52d/0x610 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8880860aa040 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 160 bytes inside of 256-byte region [ffff8880860aa040, ffff8880860aa140) The buggy address belongs to the page: page:ffffea0002182a80 count:1 mapcount:0 mapping:ffff88812c3f07c0 index:0x0 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea00024ccd48 ffffea00029973c8 ffff88812c3f07c0 raw: 0000000000000000 ffff8880860aa040 000000010000000c 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880860a9f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880860aa000: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb >ffff8880860aa080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880860aa100: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880860aa180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================