panic: Can't clear local locks with F_UNLCKSYS

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 4d504c57 stack(9): Drop unused API mode and comment that r..
git tree: freebsd
console output: https://syzkaller.appspot.com/x/log.txt?x=13f7486d200000
dashboard link: https://syzkaller.appspot.com/bug?extid=9c457a6ae014a3281eb8
userspace arch: amd64

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+9c457a...@syzkaller.appspotmail.com

panic: Can't clear local locks with F_UNLCKSYS
cpuid = 1
time = 59
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x47/frame
0xfffffe001fa0e520
vpanic() at vpanic+0x1e0/frame 0xfffffe001fa0e580
panic() at panic+0x43/frame 0xfffffe001fa0e5e0
lf_advlockasync() at lf_advlockasync+0x14dd/frame 0xfffffe001fa0e6a0
lf_advlock() at lf_advlock+0x5e/frame 0xfffffe001fa0e710
vop_stdadvlock() at vop_stdadvlock+0xf2/frame 0xfffffe001fa0e810
VOP_ADVLOCK_APV() at VOP_ADVLOCK_APV+0xc5/frame 0xfffffe001fa0e840
kern_fcntl() at kern_fcntl+0xfd1/frame 0xfffffe001fa0e8f0
kern_fcntl_freebsd() at kern_fcntl_freebsd+0x14f/frame 0xfffffe001fa0e980
amd64_syscall() at amd64_syscall+0x436/frame 0xfffffe001fa0eab0
fast_syscall_common() at fast_syscall_common+0x101/frame 0xfffffe001fa0eab0
--- syscall (198, FreeBSD ELF64, nosys), rip = 0x412e5a, rsp =
0x7fffdfffdf38, rbp = 0x3 ---
KDB: enter: panic
[ thread pid 39379 tid 100710 ]
Stopped at kdb_enter+0x6a: movq $0,kdb_why


---
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[syzbot]

syzbot has found a reproducer for the following crash on:

HEAD commit: 4d504c57 stack(9): Drop unused API mode and comment that r..
git tree: freebsd

console output: https://syzkaller.appspot.com/x/log.txt?x=12a4df6f200000

dashboard link: https://syzkaller.appspot.com/bug?extid=9c457a6ae014a3281eb8
userspace arch: amd64

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=141ee5fb200000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11a646d7200000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+9c457a...@syzkaller.appspotmail.com

login: panic: Can't clear local locks with F_UNLCKSYS
cpuid = 1
time = 1552712050

KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x47/frame

0xfffffe001fa04520
vpanic() at vpanic+0x1e0/frame 0xfffffe001fa04580
panic() at panic+0x43/frame 0xfffffe001fa045e0
lf_advlockasync() at lf_advlockasync+0x14dd/frame 0xfffffe001fa046a0
lf_advlock() at lf_advlock+0x5e/frame 0xfffffe001fa04710
vop_stdadvlock() at vop_stdadvlock+0xf2/frame 0xfffffe001fa04810
VOP_ADVLOCK_APV() at VOP_ADVLOCK_APV+0xc5/frame 0xfffffe001fa04840
kern_fcntl() at kern_fcntl+0xfd1/frame 0xfffffe001fa048f0
kern_fcntl_freebsd() at kern_fcntl_freebsd+0x14f/frame 0xfffffe001fa04980
amd64_syscall() at amd64_syscall+0x436/frame 0xfffffe001fa04ab0
fast_syscall_common() at fast_syscall_common+0x101/frame 0xfffffe001fa04ab0
--- syscall (0, FreeBSD ELF64, nosys), rip = 0x41c31a, rsp =
0x7fffffffeae8, rbp = 0x7fffffffeb40 ---
KDB: enter: panic
[ thread pid 759 tid 100094 ]