mISDN: Fix a sleep-in-atomic bug
authorJia-Ju Bai <baijiaju1990@163.com>
Wed, 31 May 2017 07:08:25 +0000 (15:08 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 13 Apr 2018 17:50:16 +0000 (19:50 +0200)
[ Upstream commit 93818da5eed63fbc17b64080406ea53b86b23309 ]

The driver may sleep under a read spin lock, and the function call path is:
send_socklist (acquire the lock by read_lock)
  skb_copy(GFP_KERNEL) --> may sleep

To fix it, the "GFP_KERNEL" is replaced with "GFP_ATOMIC".

Signed-off-by: Jia-Ju Bai <baijiaju1990@163.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/isdn/mISDN/stack.c

index 9cb4b62..b92a19a 100644 (file)
@@ -72,7 +72,7 @@ send_socklist(struct mISDN_sock_list *sl, struct sk_buff *skb)
                if (sk->sk_state != MISDN_BOUND)
                        continue;
                if (!cskb)
-                       cskb = skb_copy(skb, GFP_KERNEL);
+                       cskb = skb_copy(skb, GFP_ATOMIC);
                if (!cskb) {
                        printk(KERN_WARNING "%s no skb\n", __func__);
                        break;