Re: [PATCH] net: tipc: Fix a sleep-in-atomic bug in tipc_msg_reverse

[David Miller]

From: Jia-Ju Bai <baijiaju1990@xxxxxxx>
Date: Sat, 10 Jun 2017 17:03:35 +0800

> The kernel may sleep under a rcu read lock in tipc_msg_reverse, and the
> function call path is:
> tipc_l2_rcv_msg (acquire the lock by rcu_read_lock)
>   tipc_rcv
>     tipc_sk_rcv
>       tipc_msg_reverse
>         pskb_expand_head(GFP_KERNEL) --> may sleep
> tipc_node_broadcast
>   tipc_node_xmit_skb
>     tipc_node_xmit
>       tipc_sk_rcv
>         tipc_msg_reverse
>           pskb_expand_head(GFP_KERNEL) --> may sleep
> 
> To fix it, "GFP_KERNEL" is replaced with "GFP_ATOMIC".
> 
> Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxx>

Applied and queued up for -stable.