Debian GNU/Linux 7 syzkaller ttyS0

Warning: Permanently added '[localhost]:37952' (ECDSA) to the list of known hosts.
syzkaller login: [  116.618986][   T40] kauditd_printk_skb: 7 callbacks suppressed
[  116.619017][   T40] audit: type=1400 audit(1584459425.908:42): avc:  denied  { map } for  pid=8993 comm="syz-executor295" path="/syz-executor295538224" dev="sda1" ino=16526 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:file_t:s0 tclass=file permissive=1
[  116.739040][ T8994] IPVS: ftp: loaded support on port[0] = 21
executing program
[  116.863258][ T8994] netlink: 16 bytes leftover after parsing attributes in process `syz-executor295'.
[  117.054620][    C2] ------------[ cut here ]------------
[  117.067734][    C2] refcount_t: underflow; use-after-free.
[  117.083095][    C2] WARNING: CPU: 2 PID: 22 at lib/refcount.c:28 refcount_warn_saturate+0x1d1/0x1e0
[  117.089079][    C2] Kernel panic - not syncing: panic_on_warn set ...
[  117.089079][    C2] CPU: 2 PID: 22 Comm: ksoftirqd/2 Not tainted 5.6.0-rc6-syzkaller #0
[  117.089079][    C2] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
[  117.089079][    C2] Call Trace:
[  117.089079][    C2]  dump_stack+0x188/0x20d
[  117.089079][    C2]  ? refcount_warn_saturate+0x170/0x1e0
[  117.089079][    C2]  panic+0x2e3/0x75c
[  117.089079][    C2]  ? add_taint.cold+0x16/0x16
[  117.089079][    C2]  ? __probe_kernel_read+0x188/0x1d0
[  117.089079][    C2]  ? __warn.cold+0x14/0x35
[  117.089079][    C2]  ? __warn+0xd5/0x1c8
[  117.089079][    C2]  ? refcount_warn_saturate+0x1d1/0x1e0
[  117.089079][    C2]  __warn.cold+0x2f/0x35
[  117.089079][    C2]  ? refcount_warn_saturate+0x1d1/0x1e0
[  117.089079][    C2]  report_bug+0x27b/0x2f0
[  117.089079][    C2]  do_error_trap+0x12b/0x220
[  117.089079][    C2]  ? refcount_warn_saturate+0x1d1/0x1e0
[  117.089079][    C2]  do_invalid_op+0x32/0x40
[  117.089079][    C2]  ? refcount_warn_saturate+0x1d1/0x1e0
[  117.089079][    C2]  invalid_op+0x23/0x30
[  117.089079][    C2] RIP: 0010:refcount_warn_saturate+0x1d1/0x1e0
[  117.089079][    C2] Code: e9 db fe ff ff 48 89 df e8 0c 06 20 fe e9 8a fe ff ff e8 d2 47 e3 fd 48 c7 c7 00 aa 51 88 c6 05 24 4e d2 06 01 e8 b7 58 b5 fd <0f> 0b e9 af fe ff ff 0f 1f 84 00 00 00 00 00 41 56 41 55 41 54 55
[  117.089079][    C2] RSP: 0018:ffffc90000517c18 EFLAGS: 00010282
[  117.089079][    C2] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[  117.089079][    C2] RDX: 0000000000000100 RSI: ffffffff815c06c1 RDI: fffff520000a2f75
[  117.089079][    C2] RBP: 0000000000000003 R08: ffff88802c7506c0 R09: 0000000000000000
[  117.089079][    C2] R10: 0000000000000000 R11: 0000000000000000 R12: ffff888000598000
[  117.089079][    C2] R13: ffff888021fa0040 R14: ffff888021fa0044 R15: ffff88802c7506c0
[  117.089079][    C2]  ? vprintk_func+0x81/0x17e
[  117.089079][    C2]  ? refcount_warn_saturate+0x1d1/0x1e0
[  117.089079][    C2]  __sk_destruct+0x696/0x7c0
[  117.089079][    C2]  sk_destruct+0xc6/0x100
[  117.089079][    C2]  __sk_free+0xef/0x3d0
[  117.089079][    C2]  sk_free+0x78/0xa0
[  117.089079][    C2]  deferred_put_nlk_sk+0x151/0x2e0
[  117.089079][    C2]  rcu_core+0x5a4/0x12d0
[  117.089079][    C2]  ? __rcu_read_unlock+0x700/0x700
[  117.089079][    C2]  ? rcu_read_lock_sched_held+0x9c/0xd0
[  117.089079][    C2]  ? rcu_read_lock_any_held.part.0+0x50/0x50
[  117.089079][    C2]  __do_softirq+0x26c/0x99d
[  117.089079][    C2]  ? takeover_tasklets+0x810/0x810
[  117.089079][    C2]  run_ksoftirqd+0x89/0x100
[  117.089079][    C2]  smpboot_thread_fn+0x653/0x9e0
[  117.089079][    C2]  ? __smpboot_create_thread.part.0+0x340/0x340
[  117.089079][    C2]  ? __kthread_parkme+0x10a/0x1c0
[  117.089079][    C2]  ? __smpboot_create_thread.part.0+0x340/0x340
[  117.089079][    C2]  kthread+0x357/0x430
[  117.089079][    C2]  ? kthread_mod_delayed_work+0x1a0/0x1a0
[  117.089079][    C2]  ret_from_fork+0x24/0x30
[  117.089079][    C2] Kernel Offset: disabled
[  117.089079][    C2] Rebooting in 86400 seconds..