------------[ cut here ]------------
err == -EMSGSIZE
WARNING: net/ipv4/tcp_diag.c:628 at tcp_diag_dump_one+0x594/0x630, CPU#0: syz.2.687/8445
Modules linked in:
CPU: 0 UID: 0 PID: 8445 Comm: syz.2.687 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:tcp_diag_dump_one+0x594/0x630
Code: c6 05 0f 24 f0 05 01 48 c7 c7 a0 a6 30 8d be 9e 00 00 00 48 c7 c2 00 a9 30 8d e8 07 aa 30 f7 e9 ac fc ff ff e8 0d 05 55 f7 90 <0f> 0b 90 eb 93 44 89 f9 80 e1 07 38 c1 0f 8c d6 fd ff ff 4c 89 ff
RSP: 0018:ffffc900064d7340 EFLAGS: 00010293
RAX: ffffffff8a72f903 RBX: ffff88802315c380 RCX: ffff8881077d0000
RDX: 0000000000000000 RSI: 00000000ffffffa6 RDI: 00000000ffffffa6
RBP: 00000000ffffffa6 R08: ffffffff8a72fdb4 R09: 0000000000000000
R10: ffff888112ae68dc R11: ffffffff8a72fd70 R12: ffffc900064d7450
R13: dffffc0000000000 R14: 0000000000000400 R15: ffff888112230780
FS:  00007f66e1bf76c0(0000) GS:ffff88818d6da000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f66e1b93ff8 CR3: 000000001de22000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 inet_diag_cmd_exact+0x415/0x550
 inet_diag_handler_cmd+0x21d/0x2c0
 sock_diag_rcv_msg+0x4b0/0x5f0
 netlink_rcv_skb+0x226/0x4a0
 netlink_unicast+0x7bd/0x940
 netlink_sendmsg+0x813/0xb40
 sock_sendmsg_nosec+0x14e/0x190
 sock_write_iter+0x2de/0x3e0
 do_iter_readv_writev+0x612/0x8c0
 vfs_writev+0x343/0x990
 do_writev+0x154/0x2e0
 do_syscall_64+0x166/0x520
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f66e0d9e199
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f66e1bf7028 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007f66e1026180 RCX: 00007f66e0d9e199
RDX: 0000000000000001 RSI: 0000200000000080 RDI: 0000000000000004
RBP: 00007f66e0e350b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f66e1026218 R14: 00007f66e1026180 R15: 00007ffd8ef514c8
 </TASK>
