[PATCH AUTOSEL for 4.4 059/101] staging: wilc1000: fix unchecked return value

From: Sasha Levin
Date: Thu Mar 08 2018 - 00:06:45 EST


From: Pan Bian <bianpan2016@xxxxxxx>

[ Upstream commit 9e96652756ad647b7bcc03cb99ffc9756d7b5f93 ]

Function dev_alloc_skb() will return a NULL pointer if there is no
enough memory. However, in function WILC_WFI_mon_xmit(), its return
value is used without validation. This may result in a bad memory access
bug. This patch fixes the bug.

Signed-off-by: Pan Bian <bianpan2016@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
drivers/staging/wilc1000/linux_mon.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/staging/wilc1000/linux_mon.c b/drivers/staging/wilc1000/linux_mon.c
index 450af1b77f99..b2092c5ec7f3 100644
--- a/drivers/staging/wilc1000/linux_mon.c
+++ b/drivers/staging/wilc1000/linux_mon.c
@@ -251,6 +251,8 @@ static netdev_tx_t WILC_WFI_mon_xmit(struct sk_buff *skb,

if (skb->data[0] == 0xc0 && (!(memcmp(broadcast, &skb->data[4], 6)))) {
skb2 = dev_alloc_skb(skb->len + sizeof(struct wilc_wfi_radiotap_cb_hdr));
+ if (!skb2)
+ return -ENOMEM;

memcpy(skb_put(skb2, skb->len), skb->data, skb->len);

--
2.14.1