From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Ahern <dsahern@gmail.com>
Subject: Re: [PATCH net] net/ipv6: fix lock imbalance in ip6_route_del()
Date: Wed, 9 May 2018 11:09:15 -0600
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Cc: netdev <netdev@vger.kernel.org>,
        Eric Dumazet <eric.dumazet@gmail.com>
To: Eric Dumazet <edumazet@google.com>,
        "David S . Miller" <davem@davemloft.net>
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On 5/9/18 11:05 AM, Eric Dumazet wrote:
> WARNING: lock held when returning to user space!
> 4.17.0-rc3+ #37 Not tainted
> 
> syz-executor1/27662 is leaving the kernel with locks still held!
> 1 lock held by syz-executor1/27662:
>  #0: 00000000f661aee7 (rcu_read_lock){....}, at: ip6_route_del+0xea/0x13f0 net/ipv6/route.c:3206
> BUG: scheduling while atomic: syz-executor1/27662/0x00000002
> INFO: lockdep is turned off.
> Modules linked in:
> Kernel panic - not syncing: scheduling while atomic
> 
> CPU: 1 PID: 27662 Comm: syz-executor1 Not tainted 4.17.0-rc3+ #37

...

> 
> Fixes: 23fb93a4d3f1 ("net/ipv6: Cleanup exception and cache route handling")
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> Cc: David Ahern <dsahern@gmail.com>
> Reported-by: syzbot <syzkaller@googlegroups.com>
> ---
>  net/ipv6/route.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 

Acked-by: David Ahern <dsahern@gmail.com>

Thanks for the fix, Eric.