general protection fault in hsr_dev_change_mtu

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 13af6c74 Linux 4.19.136
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=13d8bed4900000
kernel config: https://syzkaller.appspot.com/x/.config?x=5b7578d3b5457a49
dashboard link: https://syzkaller.appspot.com/bug?extid=3a187b23dac12145bb39
compiler: gcc (GCC) 10.1.0-syz 20200507

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

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+3a187b...@syzkaller.appspotmail.com

ldm_validate_partition_table(): Disk read failed.
Dev loop0: unable to read RDB block 0
loop0: unable to read partition table
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 13635 Comm: syz-executor.4 Not tainted 4.19.136-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:hsr_dev_change_mtu+0xa2/0xd0 net/hsr/hsr_device.c:149
Code: 89 e0 5b 5d 41 5c 41 5d c3 e8 4a 90 6c fa eb e1 e8 a3 70 36 fa 49 8d 7d 10 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 75 1d 49 8b 7d 10 ba 06 00 00 00 48 c7 c6 00 7f 49 88
RSP: 0018:ffff88820c0c6b60 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 00000000000005dc RCX: ffffc9000e316000
RDX: 0000000000000002 RSI: ffffffff87333e9d RDI: 0000000000000010
RBP: ffff888054d46300 R08: 0000000000000000 R09: 00000000000005d6
R10: 0000000000000004 R11: 0000000000000000 R12: 00000000000005d6
R13: 0000000000000000 R14: ffff888054d46538 R15: 0000000000000001
FS: 00007f8cdf8ca700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056252f06e458 CR3: 0000000212acc000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__dev_set_mtu net/core/dev.c:7754 [inline]
dev_set_mtu_ext+0x339/0x580 net/core/dev.c:7807
dev_set_mtu+0x95/0x120 net/core/dev.c:7831
team_port_add drivers/net/team/team.c:1205 [inline]
team_add_slave+0x905/0x1eb0 drivers/net/team/team.c:1976
do_set_master+0x1c8/0x220 net/core/rtnetlink.c:2321
do_setlink+0x7ec/0x3540 net/core/rtnetlink.c:2455
rtnl_newlink+0xda0/0x15b0 net/core/rtnetlink.c:3077
rtnetlink_rcv_msg+0x453/0xb80 net/core/rtnetlink.c:4778
netlink_rcv_skb+0x160/0x440 net/netlink/af_netlink.c:2455
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x4d5/0x690 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x6bb/0xc40 net/netlink/af_netlink.c:1909
sock_sendmsg_nosec net/socket.c:622 [inline]
sock_sendmsg+0xc3/0x120 net/socket.c:632
___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2115
__sys_sendmsg net/socket.c:2153 [inline]
__do_sys_sendmsg net/socket.c:2162 [inline]
__se_sys_sendmsg net/socket.c:2160 [inline]
__x64_sys_sendmsg+0x132/0x220 net/socket.c:2160
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45cc79
Code: 2d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 fb b5 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f8cdf8c9c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 000000000002c080 RCX: 000000000045cc79
RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000006
RBP: 000000000078bf40 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bf0c
R13: 00007ffdbb225eaf R14: 00007f8cdf8ca9c0 R15: 000000000078bf0c
Modules linked in:
---[ end trace 2c8b0e96b148aace ]---
RIP: 0010:hsr_dev_change_mtu+0xa2/0xd0 net/hsr/hsr_device.c:149
Code: 89 e0 5b 5d 41 5c 41 5d c3 e8 4a 90 6c fa eb e1 e8 a3 70 36 fa 49 8d 7d 10 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 75 1d 49 8b 7d 10 ba 06 00 00 00 48 c7 c6 00 7f 49 88
RSP: 0018:ffff88820c0c6b60 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 00000000000005dc RCX: ffffc9000e316000
RDX: 0000000000000002 RSI: ffffffff87333e9d RDI: 0000000000000010
RBP: ffff888054d46300 R08: 0000000000000000 R09: 00000000000005d6
R10: 0000000000000004 R11: 0000000000000000 R12: 00000000000005d6
R13: 0000000000000000 R14: ffff888054d46538 R15: 0000000000000001
FS: 00007f8cdf8ca700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fece8755de0 CR3: 0000000212acc000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

[syzbot]

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