panic: Assertion in_epoch(net_epoch_preempt) failed at /syzkaller/managers/main/kernel/sys/netinet/in_mcast.c:LINE

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 6bf933c4 Revert changes to rip6_bind() from r353292. This..
git tree: freebsd
console output: https://syzkaller.appspot.com/x/log.txt?x=138b6920e00000
dashboard link: https://syzkaller.appspot.com/bug?extid=c7892411968c2596fae3

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+c78924...@syzkaller.appspotmail.com

panic: Assertion in_epoch(net_epoch_preempt) failed at
/syzkaller/managers/main/kernel/sys/netinet/in_mcast.c:1319
cpuid = 1
time = 985
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x47/frame
0xfffffe00243d94c0
vpanic() at vpanic+0x1e0/frame 0xfffffe00243d9520
panic() at panic+0x43/frame 0xfffffe00243d9580
in_leavegroup_locked() at in_leavegroup_locked+0x215/frame
0xfffffe00243d95e0
inp_setmoptions() at inp_setmoptions+0x1290/frame 0xfffffe00243d97b0
ip_ctloutput() at ip_ctloutput+0x823/frame 0xfffffe00243d9810
rip_ctloutput() at rip_ctloutput+0x2c9/frame 0xfffffe00243d9850
sosetopt() at sosetopt+0x101/frame 0xfffffe00243d98d0
kern_setsockopt() at kern_setsockopt+0x14f/frame 0xfffffe00243d9950
sys_setsockopt() at sys_setsockopt+0x33/frame 0xfffffe00243d9980
amd64_syscall() at amd64_syscall+0x477/frame 0xfffffe00243d9ab0
fast_syscall_common() at fast_syscall_common+0x101/frame 0xfffffe00243d9ab0
--- syscall (198, FreeBSD ELF64, nosys), rip = 0x4132aa, rsp =
0x7fffdfffdf38, rbp = 0x5 ---
KDB: enter: panic
[ thread pid 18097 tid 100235 ]
Stopped at kdb_enter+0x6a: movq $0,kdb_why


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.