panic: udp_output: shared udbinfo lock, excl inp lock

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 84b9791b bridge: Fix panic if the STP root is removed
git tree: freebsd
console output: https://syzkaller.appspot.com/x/log.txt?x=1305e76f200000
dashboard link: https://syzkaller.appspot.com/bug?extid=1f5c6800e4f99bdb1a48
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+1f5c68...@syzkaller.appspotmail.com

panic: udp_output: shared udbinfo lock, excl inp lock
cpuid = 1
time = 4294967443
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x47/frame
0xfffffe00212d1560
vpanic() at vpanic+0x1e0/frame 0xfffffe00212d15c0
panic() at panic+0x43/frame 0xfffffe00212d1620
udp_send() at udp_send+0x1377/frame 0xfffffe00212d1730
sosend_dgram() at sosend_dgram+0x550/frame 0xfffffe00212d17a0
sosend() at sosend+0xc6/frame 0xfffffe00212d1810
kern_sendit() at kern_sendit+0x35e/frame 0xfffffe00212d18c0
sendit() at sendit+0x226/frame 0xfffffe00212d1920
sys_sendmsg() at sys_sendmsg+0x8b/frame 0xfffffe00212d1980
amd64_syscall() at amd64_syscall+0x436/frame 0xfffffe00212d1ab0
fast_syscall_common() at fast_syscall_common+0x101/frame 0xfffffe00212d1ab0
--- syscall (198, FreeBSD ELF64, nosys), rip = 0x412e5a, rsp =
0x7fffdfffdf38, rbp = 0x3 ---
KDB: enter: panic
[ thread pid 34575 tid 100824 ]
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: 84b9791b bridge: Fix panic if the STP root is removed
git tree: freebsd

console output: https://syzkaller.appspot.com/x/log.txt?x=145db9fb200000

dashboard link: https://syzkaller.appspot.com/bug?extid=1f5c6800e4f99bdb1a48
userspace arch: amd64

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1051e3e7200000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=115e57db200000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+1f5c68...@syzkaller.appspotmail.com

login: panic: udp_output: shared udbinfo lock, excl inp lock
cpuid = 1
time = 1552655206

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

0xfffffe0021218560
vpanic() at vpanic+0x1e0/frame 0xfffffe00212185c0
panic() at panic+0x43/frame 0xfffffe0021218620
udp_send() at udp_send+0x1377/frame 0xfffffe0021218730
sosend_dgram() at sosend_dgram+0x550/frame 0xfffffe00212187a0
sosend() at sosend+0xc6/frame 0xfffffe0021218810
kern_sendit() at kern_sendit+0x35e/frame 0xfffffe00212188c0
sendit() at sendit+0x226/frame 0xfffffe0021218920
sys_sendmsg() at sys_sendmsg+0x8b/frame 0xfffffe0021218980
amd64_syscall() at amd64_syscall+0x436/frame 0xfffffe0021218ab0
fast_syscall_common() at fast_syscall_common+0x101/frame 0xfffffe0021218ab0
--- syscall (0, FreeBSD ELF64, nosys), rip = 0x41c3aa, rsp =
0x7fffffffeae8, rbp = 0x7fffffffeb40 ---
KDB: enter: panic
[ thread pid 759 tid 100098 ]

[ema...@freebsdfoundation.org]

On Friday, March 15, 2019 at 8:54:04 AM UTC-4, syzbot wrote:

Hello,

syzbot found the following crash on:

HEAD commit:    84b9791b bridge: Fix panic if the STP root is removed
git tree:       freebsd
console output: https://syzkaller.appspot.com/x/log.txt?x=1305e76f200000
dashboard link: https://syzkaller.appspot.com/bug?extid=1f5c6800e4f99bdb1a48
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+1f5c68...@syzkaller.appspotmail.com

Proposed fix in https://reviews.freebsd.org/D19594