WARNING in hsr_forward_skb

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 4d552acf Linux 4.19.34
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1170745b200000
kernel config: https://syzkaller.appspot.com/x/.config?x=c95a88291f095edd
dashboard link: https://syzkaller.appspot.com/bug?extid=fed9e12307896dd86f23
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=129332dd200000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=174ac5ed200000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+fed9e1...@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
------------[ cut here ]------------
net/hsr/hsr_forward.c:366: Malformed frame (port_src hsr0)
WARNING: CPU: 0 PID: 7750 at net/hsr/hsr_forward.c:365
hsr_forward_skb+0x122f/0x1c10 net/hsr/hsr_forward.c:365
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 7750 Comm: syz-executor577 Not tainted 4.19.34 #2
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x172/0x1f0 lib/dump_stack.c:113
panic+0x263/0x51d kernel/panic.c:185
__warn.cold+0x20/0x54 kernel/panic.c:540
report_bug+0x263/0x2b0 lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:178 [inline]
fixup_bug arch/x86/kernel/traps.c:173 [inline]
do_error_trap+0x204/0x360 arch/x86/kernel/traps.c:296
do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316
invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:997
RIP: 0010:hsr_forward_skb+0x122f/0x1c10 net/hsr/hsr_forward.c:365
Code: fb ff ff e8 43 13 85 fa 4c 89 e9 ba 6e 01 00 00 48 c7 c6 60 6e fa 87
48 c7 c7 a0 6e fa 87 c6 05 22 c5 4f 02 01 e8 3f ee 58 fa <0f> 0b 48 b8 00
00 00 00 00 fc ff df 4c 89 fa 48 c1 ea 03 80 3c 02
RSP: 0018:ffff88808529f8e8 EFLAGS: 00010282
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8155d206 RDI: ffffed1010a53f0f
RBP: ffff88808529f988 R08: ffff888096b1c040 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88808284d780
R13: ffff88809adf6a00 R14: ffff88809e924d00 R15: ffff88809e924d10
hsr_dev_xmit+0x72/0xa0 net/hsr/hsr_device.c:242
__netdev_start_xmit include/linux/netdevice.h:4300 [inline]
netdev_start_xmit include/linux/netdevice.h:4309 [inline]
dev_direct_xmit+0x352/0x650 net/core/dev.c:3895
packet_direct_xmit+0xfb/0x170 net/packet/af_packet.c:246
packet_snd net/packet/af_packet.c:2933 [inline]
packet_sendmsg+0x3a95/0x6330 net/packet/af_packet.c:2958
sock_sendmsg_nosec net/socket.c:622 [inline]
sock_sendmsg+0xdd/0x130 net/socket.c:632
__sys_sendto+0x262/0x380 net/socket.c:1787
__do_sys_sendto net/socket.c:1799 [inline]
__se_sys_sendto net/socket.c:1795 [inline]
__x64_sys_sendto+0xe1/0x1a0 net/socket.c:1795
do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4419e9
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
ff 0f 83 bb 10 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffe73c658d8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004419e9
RDX: 000000000000000e RSI: 00000000200000c0 RDI: 0000000000000003
RBP: 00000000004a9090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402f30
R13: 0000000000402fc0 R14: 0000000000000000 R15: 0000000000000000
Kernel Offset: disabled
Rebooting in 86400 seconds..


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