Subject: [PATCH 29/62] net: qualcomm: rmnet: Fix incorrect allocation flag in receive path

From: Subash Abhinov Kasiviswanathan <[email-masked]>
Date: Tue, 2 Oct 2018 18:52:03 -0600

[ Upstream commit ec405641e2b73160e26ef17580d0cf28565d146c ]

The incoming skb needs to be reallocated in case the headroom
is not sufficient to adjust the ethernet header. This allocation
needs to be atomic otherwise it results in this splat

 [<600601bb>] ___might_sleep+0x185/0x1a3
 [<603f6314>] ? _raw_spin_unlock_irqrestore+0x0/0x27
 [<60069bb0>] ? __wake_up_common_lock+0x95/0xd1
 [<600602b0>] __might_sleep+0xd7/0xe2
 [<60065598>] ? enqueue_task_fair+0x112/0x209
 [<600eea13>] __kmalloc_track_caller+0x5d/0x124
 [<600ee9b6>] ? __kmalloc_track_caller+0x0/0x124
 [<602696d5>] __kmalloc_reserve.isra.34+0x30/0x7e
 [<603f629b>] ? _raw_spin_lock_irqsave+0x0/0x3d
 [<6026b744>] pskb_expand_head+0xbf/0x310
 [<6025ca6a>] rmnet_rx_handler+0x7e/0x16b
 [<6025c9ec>] ? rmnet_rx_handler+0x0/0x16b
 [<6027ad0c>] __netif_receive_skb_core+0x301/0x96f
 [<60033c17>] ? set_signals+0x0/0x40
 [<6027bbcb>] __netif_receive_skb+0x24/0x8e

Fixes: 74692caf1b0b ("net: qualcomm: rmnet: Process packets over ethernet")
Signed-off-by: Sean Tranchetti <[email-masked]>
Signed-off-by: Subash Abhinov Kasiviswanathan <[email-masked]>
Signed-off-by: David S. Miller <[email-masked]>
---
 drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c
index 1f98d65473cf..11167abe5934 100644
--- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c
+++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c
@@ -113,7 +113,7 @@ rmnet_map_ingress_handler(struct sk_buff *skb,
 	struct sk_buff *skbn;
 
 	if (skb->dev->type == ARPHRD_ETHER) {
-		if (pskb_expand_head(skb, ETH_HLEN, 0, GFP_KERNEL)) {
+		if (pskb_expand_head(skb, ETH_HLEN, 0, GFP_ATOMIC)) {
 			kfree_skb(skb);
 			return;
 		}
-- 
2.17.2