diff options
| author | Jia-Ju Bai <baijiaju1990@163.com> | 2017-06-10 11:49:39 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-06-11 01:19:45 +0300 |
| commit | f146e872eb12ebbe92d8e583b2637e0741440db3 (patch) | |
| tree | 11df674fe1f70d91c86b2a63cfec66f8823ecfd1 | |
| parent | 5aa32f53ab93175442dffbd95a231d0798cab4d1 (diff) | |
| download | linux-f146e872eb12ebbe92d8e583b2637e0741440db3.tar.xz | |
net: caif: Fix a sleep-in-atomic bug in cfpkt_create_pfx
The kernel may sleep under a rcu read lock in cfpkt_create_pfx, and the
function call path is:
cfcnfg_linkup_rsp (acquire the lock by rcu_read_lock)
cfctrl_linkdown_req
cfpkt_create
cfpkt_create_pfx
alloc_skb(GFP_KERNEL) --> may sleep
cfserl_receive (acquire the lock by rcu_read_lock)
cfpkt_split
cfpkt_create_pfx
alloc_skb(GFP_KERNEL) --> may sleep
There is "in_interrupt" in cfpkt_create_pfx to decide use "GFP_KERNEL" or
"GFP_ATOMIC". In this situation, "GFP_KERNEL" is used because the function
is called under a rcu read lock, instead in interrupt.
To fix it, only "GFP_ATOMIC" is used in cfpkt_create_pfx.
Signed-off-by: Jia-Ju Bai <baijiaju1990@163.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/caif/cfpkt_skbuff.c | 6 |
1 files changed, 1 insertions, 5 deletions
diff --git a/net/caif/cfpkt_skbuff.c b/net/caif/cfpkt_skbuff.c index 59ce1fcc220c..71b6ab240dea 100644 --- a/net/caif/cfpkt_skbuff.c +++ b/net/caif/cfpkt_skbuff.c @@ -81,11 +81,7 @@ static struct cfpkt *cfpkt_create_pfx(u16 len, u16 pfx) { struct sk_buff *skb; - if (likely(in_interrupt())) - skb = alloc_skb(len + pfx, GFP_ATOMIC); - else - skb = alloc_skb(len + pfx, GFP_KERNEL); - + skb = alloc_skb(len + pfx, GFP_ATOMIC); if (unlikely(skb == NULL)) return NULL; |