WARNING in hsr_forward_skb

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 2bf3258a Linux 4.14.125
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=13c6fc3ea00000
kernel config: https://syzkaller.appspot.com/x/.config?x=4d8d355e5f0fe72c
dashboard link: https://syzkaller.appspot.com/bug?extid=194a3141c56ae993aa31
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1675c6b6a00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=102b1396a00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+194a31...@syzkaller.appspotmail.com

IPv6: ADDRCONF(NETDEV_CHANGE): team0: link becomes ready
IPv6: ADDRCONF(NETDEV_UP): vxcan1: link is not ready
8021q: adding VLAN 0 to HW filter on device batadv0
net/hsr/hsr_forward.c:366: Malformed frame (port_src hsr0)
------------[ cut here ]------------
WARNING: CPU: 0 PID: 7118 at net/hsr/hsr_forward.c:365
hsr_forward_skb.cold+0xce/0x100 net/hsr/hsr_forward.c:365
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 7118 Comm: syz-executor758 Not tainted 4.14.125 #19
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x138/0x19c lib/dump_stack.c:53
panic+0x1f2/0x426 kernel/panic.c:182
__warn.cold+0x2f/0x36 kernel/panic.c:546
report_bug+0x216/0x254 lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:177 [inline]
fixup_bug arch/x86/kernel/traps.c:172 [inline]
do_error_trap+0x1bb/0x310 arch/x86/kernel/traps.c:295
do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:314
invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:960
RIP: 0010:hsr_forward_skb.cold+0xce/0x100 net/hsr/hsr_forward.c:365
RSP: 0018:ffff88809b6af958 EFLAGS: 00010282
RAX: 000000000000003a RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff866d0ca0 RDI: ffffed10136d5f21
RBP: ffff88809b6af9f0 R08: 000000000000003a R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880975a0080
R13: ffff88809ede8a00 R14: ffff88807deab480 R15: ffff88807deab490
hsr_dev_xmit+0x72/0xa0 net/hsr/hsr_device.c:242
__netdev_start_xmit include/linux/netdevice.h:4033 [inline]
netdev_start_xmit include/linux/netdevice.h:4042 [inline]
packet_direct_xmit+0x431/0x640 net/packet/af_packet.c:269
packet_snd net/packet/af_packet.c:2973 [inline]
packet_sendmsg+0x328f/0x5920 net/packet/af_packet.c:2998
sock_sendmsg_nosec net/socket.c:646 [inline]
sock_sendmsg+0xce/0x110 net/socket.c:656
SYSC_sendto+0x206/0x310 net/socket.c:1763
SyS_sendto+0x40/0x50 net/socket.c:1731
do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x441a09
RSP: 002b:00007fff42fc9938 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000441a09
RDX: 000000000000000e RSI: 0000000020000040 RDI: 0000000000000003
RBP: 00000000004a90b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402f50
R13: 0000000000402fe0 R14: 0000000000000000 R15: 0000000000000000
Kernel Offset: disabled
Rebooting in 86400 seconds..


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