From: Jia-Ju Bai <baijiaju1990@163.com>
Date: Wed, 31 May 2017 01:40:11 +0000 (+0800)
Subject: isdn: Fix a sleep-in-atomic bug
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=e8f4ae85439f34bec3b0ab69223a41809dab28c9;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git

isdn: Fix a sleep-in-atomic bug

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>
---

diff --git a/drivers/isdn/i4l/isdn_ppp.c b/drivers/isdn/i4l/isdn_ppp.c
index d07dd5196ffc..8aa158a09180 100644
--- a/drivers/isdn/i4l/isdn_ppp.c
+++ b/drivers/isdn/i4l/isdn_ppp.c
@@ -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;