[ath9k-devel] [PATCH] net: wireless: wcn36xx: fix potential NULL pointer dereference

[Michal Nazarewicz <mpn@google.com>]

From: Michal Nazarewicz <mina86@mina86.com>

If kmalloc fails wcn36xx_smd_rsp_process will attempt to dereference
a NULL pointer.  There might be a better error recovery then just
printing an error, but printing an error message is better then the
current behaviour.

Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
---
 drivers/net/wireless/ath/wcn36xx/smd.c | 22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/drivers/net/wireless/ath/wcn36xx/smd.c b/drivers/net/wireless/ath/wcn36xx/smd.c
index de9eb2c..10d6ae9 100644
--- a/drivers/net/wireless/ath/wcn36xx/smd.c
+++ b/drivers/net/wireless/ath/wcn36xx/smd.c
@@ -2041,13 +2041,23 @@ static void wcn36xx_smd_rsp_process(struct wcn36xx *wcn, void *buf, size_t len)
 	case WCN36XX_HAL_DELETE_STA_CONTEXT_IND:
 		mutex_lock(&wcn->hal_ind_mutex);
 		msg_ind = kmalloc(sizeof(*msg_ind), GFP_KERNEL);
-		msg_ind->msg_len = len;
-		msg_ind->msg = kmalloc(len, GFP_KERNEL);
-		memcpy(msg_ind->msg, buf, len);
-		list_add_tail(&msg_ind->list, &wcn->hal_ind_queue);
-		queue_work(wcn->hal_ind_wq, &wcn->hal_ind_work);
-		wcn36xx_dbg(WCN36XX_DBG_HAL, "indication arrived\n");
+		if (msg_ind) {
+			msg_ind->msg_len = len;
+			msg_ind->msg = kmalloc(len, GFP_KERNEL);
+			memcpy(msg_ind->msg, buf, len);
+			list_add_tail(&msg_ind->list, &wcn->hal_ind_queue);
+			queue_work(wcn->hal_ind_wq, &wcn->hal_ind_work);
+			wcn36xx_dbg(WCN36XX_DBG_HAL, "indication arrived\n");
+		}
 		mutex_unlock(&wcn->hal_ind_mutex);
+		if (!msg_ind) {
+			/*
+			 * FIXME: Do something smarter then just
+			 * printing an error when allocation fails.
+			 */
+			wcn36xx_err("Run out of memory while hnadling SMD_EVENT (%d)\n",
+				    msg_header->msg_type);
+		}
 		break;
 	default:
 		wcn36xx_err("SMD_EVENT (%d) not supported\n",
-- 
1.8.4.1