Re: possible deadlock in dev_mc_unsync

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger crash:

Reported-and-tested-by: syzbot+08e3d39f3eb8643216be@xxxxxxxxxxxxxxxxxxxxxxxxx

Tested on:

commit:         152c6a4d genetlink: get rid of family->attrbuf
git tree:       https://github.com/congwang/linux.git net
kernel config:  https://syzkaller.appspot.com/x/.config?x=bf3aec367b9ab569
dashboard link: https://syzkaller.appspot.com/bug?extid=08e3d39f3eb8643216be
compiler:       gcc (GCC) 10.1.0-syz 20200507

Note: testing is done by a robot and is best-effort only.