isdn: Fix a sleep-in-atomic bug
authorJia-Ju Bai <baijiaju1990@163.com>
Wed, 31 May 2017 01:40:11 +0000 (09:40 +0800)
committerDavid S. Miller <davem@davemloft.net>
Wed, 31 May 2017 18:38:10 +0000 (14:38 -0400)
The driver may sleep under a spin lock, the function call path is:
isdn_ppp_mp_receive (acquire the lock)
  isdn_ppp_mp_reassembly
    isdn_ppp_push_higher
      isdn_ppp_decompress
        isdn_ppp_ccp_reset_trans
          isdn_ppp_ccp_reset_alloc_state
            kzalloc(GFP_KERNEL) --> may sleep

To fixed 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>
drivers/isdn/i4l/isdn_ppp.c

index d07dd5196ffca59c11532051fb88e2ecdc7326c9..8aa158a091806fd7d3107ed56b8550198be7b9a0 100644 (file)
@@ -2364,7 +2364,7 @@ static struct ippp_ccp_reset_state *isdn_ppp_ccp_reset_alloc_state(struct ippp_s
                       id);
                return NULL;
        } else {
-               rs = kzalloc(sizeof(struct ippp_ccp_reset_state), GFP_KERNEL);
+               rs = kzalloc(sizeof(struct ippp_ccp_reset_state), GFP_ATOMIC);
                if (!rs)
                        return NULL;
                rs->state = CCPResetIdle;