wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50 IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready ================================================================== BUG: KASAN: use-after-free in snd_seq_timer_interrupt+0x2c8/0x370 sound/core/seq/seq_timer.c:145 Read of size 8 at addr ffff8880a5868cd8 by task syz-executor.0/8462 CPU: 1 PID: 8462 Comm: syz-executor.0 Not tainted 4.19.206-syzkaller #0 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+0x17c/0x226 lib/dump_stack.c:118 print_address_description.cold.6+0x9/0x211 mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report mm/kasan/report.c:412 [inline] kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:396 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 snd_seq_timer_interrupt+0x2c8/0x370 sound/core/seq/seq_timer.c:145 snd_timer_interrupt sound/core/timer.c:877 [inline] snd_timer_interrupt+0x617/0x1080 sound/core/timer.c:789 snd_timer_s_function+0xa7/0x120 sound/core/timer.c:1116 call_timer_fn+0x14c/0x510 kernel/time/timer.c:1338 expire_timers+0x255/0x3a0 kernel/time/timer.c:1375 __run_timers kernel/time/timer.c:1696 [inline] run_timer_softirq+0x1dc/0x570 kernel/time/timer.c:1709 __do_softirq+0x25f/0x919 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:372 [inline] irq_exit+0x17f/0x1c0 kernel/softirq.c:412 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x13e/0x540 arch/x86/kernel/apic/apic.c:1098 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894 RIP: 0010:pipe_write+0x237/0xd00 fs/pipe.c:468 Code: ff 0f 00 00 0f 86 fd 02 00 00 48 63 d0 48 01 55 a0 4c 89 fa 48 c1 ea 03 42 80 3c 2a 00 0f 85 88 08 00 00 49 8d 7f 10 4d 89 1f <48> 89 fa 48 c1 ea 03 42 80 3c 2a 00 0f 85 5d 08 00 00 49 8d 7f 08 RSP: 0018:ffff8880aacc7bf8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 000000000000000c RBX: 0000000000000000 RCX: ffff8880aacc7d68 RDX: 1ffff110154af03a RSI: 1ffff11015598fb0 RDI: ffff8880aa5781e0 RBP: ffff8880aacc7c70 R08: 0000000000000000 R09: ffff8880aacc7cd0 R10: ffff8880aacc7d80 R11: ffffea00025c2d80 R12: ffff88809a9d0ac0 R13: dffffc0000000000 R14: ffff8880a1decd40 R15: ffff8880aa5781d0 call_write_iter include/linux/fs.h:1821 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x443/0x890 fs/read_write.c:487 vfs_write+0x150/0x4d0 fs/read_write.c:549 ksys_write+0x103/0x260 fs/read_write.c:599 __do_sys_write fs/read_write.c:611 [inline] __se_sys_write fs/read_write.c:608 [inline] __x64_sys_write+0x6e/0xb0 fs/read_write.c:608 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4192bf Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 99 fd ff ff 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 cc fd ff ff 48 RSP: 002b:00007fff423fe7a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000000001e RCX: 00000000004192bf RDX: 000000000000000c RSI: 00007fff423fe8a0 RDI: 00000000000000f8 RBP: 00007fff423fe83c R08: 0000000000000000 R09: 0000000db167ed56 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000032 R13: 000000000000bcc7 R14: 0000000000000006 R15: 00007fff423fe8a0 Allocated by task 10268: save_stack mm/kasan/kasan.c:448 [inline] set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc.part.1+0x62/0xf0 mm/kasan/kasan.c:553 kasan_kmalloc+0xaf/0xc0 mm/kasan/kasan.c:538 kmem_cache_alloc_trace+0x152/0x3a0 mm/slab.c:3625 kmalloc include/linux/slab.h:515 [inline] kzalloc include/linux/slab.h:709 [inline] queue_new sound/core/seq/seq_queue.c:113 [inline] snd_seq_queue_alloc+0x52/0x4d0 sound/core/seq/seq_queue.c:185 snd_seq_ioctl_create_queue+0xaa/0x2e0 sound/core/seq/seq_clientmgr.c:1531 snd_seq_ioctl+0x1c6/0x3e0 sound/core/seq/seq_clientmgr.c:2140 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x196/0x10c0 fs/ioctl.c:688 ksys_ioctl+0x62/0x90 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:710 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 10264: save_stack mm/kasan/kasan.c:448 [inline] set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x13c/0x220 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3503 [inline] kfree+0xcf/0x220 mm/slab.c:3822 queue_delete+0x8b/0xa0 sound/core/seq/seq_queue.c:156 snd_seq_queue_client_leave+0x27/0x110 sound/core/seq/seq_queue.c:592 seq_free_client1.part.8+0xef/0x260 sound/core/seq/seq_clientmgr.c:263 seq_free_client1 sound/core/seq/seq_clientmgr.c:256 [inline] seq_free_client+0x5c/0xd0 sound/core/seq/seq_clientmgr.c:285 snd_seq_release+0x48/0xe0 sound/core/seq/seq_clientmgr.c:366 __fput+0x249/0x7f0 fs/file_table.c:278 ____fput+0x9/0x10 fs/file_table.c:309 task_work_run+0x108/0x180 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x185/0x1e0 arch/x86/entry/common.c:167 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x413/0x4e0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8880a5868c80 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 88 bytes inside of 512-byte region [ffff8880a5868c80, ffff8880a5868e80) The buggy address belongs to the page: page:ffffea0002961a00 count:1 mapcount:0 mapping:ffff88813bff6940 index:0xffff8880a5868000 flags: 0xfff00000000100(slab) raw: 00fff00000000100 ffffea0002cdb0c8 ffffea0002cdb688 ffff88813bff6940 raw: ffff8880a5868000 ffff8880a5868000 0000000100000005 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a5868b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880a5868c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880a5868c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880a5868d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a5868d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: ff 0f decl (%rdi) 2: 00 00 add %al,(%rax) 4: 0f 86 fd 02 00 00 jbe 0x307 a: 48 63 d0 movslq %eax,%rdx d: 48 01 55 a0 add %rdx,-0x60(%rbp) 11: 4c 89 fa mov %r15,%rdx 14: 48 c1 ea 03 shr $0x3,%rdx 18: 42 80 3c 2a 00 cmpb $0x0,(%rdx,%r13,1) 1d: 0f 85 88 08 00 00 jne 0x8ab 23: 49 8d 7f 10 lea 0x10(%r15),%rdi 27: 4d 89 1f mov %r11,(%r15) * 2a: 48 89 fa mov %rdi,%rdx <-- trapping instruction 2d: 48 c1 ea 03 shr $0x3,%rdx 31: 42 80 3c 2a 00 cmpb $0x0,(%rdx,%r13,1) 36: 0f 85 5d 08 00 00 jne 0x899 3c: 49 8d 7f 08 lea 0x8(%r15),%rdi