tree 711dba8be73a7b425c523b09098b57f7f77d330e
parent 06e55addd3f40b5294e448c2cb7605ca4f28c2e3
author Eric Dumazet <edumazet@google.com> 1538171508 -0700
committer David S. Miller <davem@davemloft.net> 1538461648 -0700

tun: initialize napi_mutex unconditionally

This is the first part to fix following syzbot report :

console output: https://syzkaller.appspot.com/x/log.txt?x=145378e6400000
kernel config:  https://syzkaller.appspot.com/x/.config?x=443816db871edd66
dashboard link: https://syzkaller.appspot.com/bug?extid=e662df0ac1d753b57e80

Following patch is fixing the race condition, but it seems safer
to initialize this mutex at tfile creation anyway.

Fixes: 90e33d459407 ("tun: enable napi_gro_frags() for TUN/TAP driver")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot+e662df0ac1d753b57e80@syzkaller.appspotmail.com
Signed-off-by: David S. Miller <davem@davemloft.net>