panic: mtx_lock() of spin mutex (null) @ /syzkaller/managers/main/kernel/sys/kern/uipc_sockbuf.c:434
cpuid = 1
time = 1621497900
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x47/frame 0xfffffe00037790a0
vpanic() at vpanic+0x1c7/frame 0xfffffe0003779100
panic() at panic+0x43/frame 0xfffffe0003779160
__mtx_lock_flags() at __mtx_lock_flags+0x202/frame 0xfffffe00037791c0
socantrcvmore() at socantrcvmore+0x2c/frame 0xfffffe00037791e0
sctp_notify_assoc_change() at sctp_notify_assoc_change+0x5b8/frame 0xfffffe0003779250
sctp_process_control() at sctp_process_control+0x9040/frame 0xfffffe00037796e0
sctp_common_input_processing() at sctp_common_input_processing+0x7d0/frame 0xfffffe0003779860
sctp6_input_with_port() at sctp6_input_with_port+0x302/frame 0xfffffe0003779960
sctp6_input() at sctp6_input+0x1f/frame 0xfffffe0003779980
ip6_input() at ip6_input+0x1810/frame 0xfffffe0003779a90
swi_net() at swi_net+0x20d/frame 0xfffffe0003779b10
ithread_loop() at ithread_loop+0x33f/frame 0xfffffe0003779bb0
fork_exit() at fork_exit+0xb3/frame 0xfffffe0003779bf0
fork_trampoline() at fork_trampoline+0xe/frame 0xfffffe0003779bf0
--- trap 0, rip = 0, rsp = 0, rbp = 0 ---
KDB: enter: panic
[ thread pid 12 tid 100032 ]
Stopped at      kdb_enter+0x67: movq    $0,0x16391de(%rip)
db> 
db> set $lines = 0
db> set $maxwidth = 0
db>