syzbot has bisected this issue to:

commit bcd623d8e9fa5f82bbd8cd464dc418d24139157b
Author: Xin Long [off-list ref]
Date:   Thu Oct 29 07:05:05 2020 +0000

    sctp: call sk_setup_caps in sctp_packet_transmit instead

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=14df9cb8500000
start commit:   68bb4665 Merge branch 'l2-multicast-forwarding-for-ocelot-..
git tree:       net-next
final oops:     https://syzkaller.appspot.com/x/report.txt?x=16df9cb8500000
console output: https://syzkaller.appspot.com/x/log.txt?x=12df9cb8500000
kernel config:  https://syzkaller.appspot.com/x/.config?x=eac680ae76558a0e
dashboard link: https://syzkaller.appspot.com/bug?extid=5be8aebb1b7dfa90ef31
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=11286398500000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=11bbf398500000

Reported-by: syzbot+5be8aebb1b7dfa90ef31@syzkaller.appspotmail.com
Fixes: bcd623d8e9fa ("sctp: call sk_setup_caps in sctp_packet_transmit instead")

For information about bisection process see: https://goo.gl/tpsmEJ#bisection