[PATCH] rtlwifi: rtl8822b: fix a missing check of alloc_skb

From: Kangjie Lu
Date: Sat Dec 22 2018 - 17:58:45 EST


__netdev_alloc_skb() return NULl when it fails. skb_put() further uses
it even when the allocation fails, leading to NULL pointer dereference.
The fix inserts a check for the return value of __netdev_alloc_skb().

Signed-off-by: Kangjie Lu <kjlu@xxxxxxx>
---
drivers/staging/rtlwifi/rtl8822be/fw.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/staging/rtlwifi/rtl8822be/fw.c b/drivers/staging/rtlwifi/rtl8822be/fw.c
index a40396614814..f061dd1382aa 100644
--- a/drivers/staging/rtlwifi/rtl8822be/fw.c
+++ b/drivers/staging/rtlwifi/rtl8822be/fw.c
@@ -486,6 +486,8 @@ bool rtl8822b_halmac_cb_write_data_h2c(struct rtl_priv *rtlpriv, u8 *buf,

/* without GFP_DMA, pci_map_single() may not work */
skb = __netdev_alloc_skb(NULL, size, GFP_ATOMIC | GFP_DMA);
+ if (!skb)
+ return false;
memcpy((u8 *)skb_put(skb, size), buf, size);

return _rtl8822be_send_bcn_or_cmd_packet(rtlpriv->hw, skb, H2C_QUEUE);
--
2.17.2 (Apple Git-113)