------------[ cut here ]------------
skb_is_nonlinear(skb)
WARNING: ./include/linux/skbuff.h:3354 at skb_trim+0x112/0x1a0, CPU#0: sshd/5530
Modules linked in:
CPU: 0 UID: 0 PID: 5530 Comm: sshd 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:skb_trim+0x112/0x1a0
Code: 04 28 84 c0 0f 85 81 00 00 00 41 89 1e eb 05 e8 e4 0f 1d f8 5b 41 5c 41 5d 41 5e 41 5f 5d e9 85 2e 3d 02 cc e8 cf 0f 1d f8 90 <0f> 0b 90 eb e5 44 89 e1 80 e1 07 80 c1 03 38 c1 0f 8c 12 ff ff ff
RSP: 0018:ffffc900000070f8 EFLAGS: 00010246
RAX: ffffffff89aabae1 RBX: 00000000000004bc RCX: ffff88810e429e00
RDX: 0000000000000100 RSI: 0000000000000100 RDI: 0000000000000000
RBP: 00000000000000e6 R08: 0000000000000100 R09: 1ffff110216ae020
R10: dffffc0000000000 R11: ffffed10216ae021 R12: ffff88810ea0caf4
R13: dffffc0000000000 R14: ffff88810ea0ca80 R15: 1ffff11021d4195e
FS:  00007fb4e3a8e800(0000) GS:ffff88818d6d2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f82bd267d58 CR3: 0000000117048000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 sctp_ulpevent_make_rcvmsg+0x3bd/0x970
 sctp_ulpq_tail_data+0xd1/0xed0
 sctp_do_sm+0x1afc/0x5dd0
 sctp_assoc_bh_rcv+0x401/0x6f0
 sctp_rcv+0x11e5/0x18b0
 sctp6_rcv+0x39/0x70
 ip6_protocol_deliver_rcu+0xe8c/0x1680
 ip6_input_finish+0x191/0x370
 NF_HOOK+0x336/0x3c0
 ip6_input+0x16a/0x270
 NF_HOOK+0x336/0x3c0
 process_backlog+0x795/0x18b0
 __napi_poll+0xaa/0x330
 net_rx_action+0x61d/0xf50
 handle_softirqs+0x226/0x860
 do_softirq+0x77/0xd0
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x100/0x140
 __dev_queue_xmit+0x1edc/0x3820
 ip_finish_output2+0xbda/0x10b0
 ip_output+0x29f/0x450
 __ip_queue_xmit+0x10df/0x1b10
 __tcp_transmit_skb+0x2d18/0x47c0
 tcp_write_xmit+0x1bfa/0x6400
 __tcp_push_pending_frames+0x96/0x380
 tcp_sendmsg_locked+0x47da/0x5400
 tcp_sendmsg+0x2f/0x50
 sock_sendmsg_nosec+0x10e/0x180
 sock_write_iter+0x2de/0x3e0
 vfs_write+0x612/0xba0
 ksys_write+0x150/0x270
 do_syscall_64+0x166/0x520
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb4e3716bf2
Code: 89 c7 48 89 44 24 08 e8 7b 34 fa ff 48 8b 44 24 08 48 83 c4 28 c3 c3 64 8b 04 25 18 00 00 00 85 c0 75 20 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 6f 48 8b 15 07 a2 0d 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffe5b791798 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000054 RCX: 00007fb4e3716bf2
RDX: 0000000000000054 RSI: 000055bdac772e70 RDI: 0000000000000004
RBP: 000055bdac7510e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000055bd806aeaa4
R13: 00000000000000cf R14: 000055bd806af3e8 R15: 00007ffe5b791808
 </TASK>
