[PATCH] [net] Fix memory leak in htc_connect_service

[Takeshi Misawa]

Timeout occurs in htc_connect_service(), then this function returns
without freeing skb.

Fix this by going to err path.

syzbot report:
https://syzkaller.appspot.com/bug?id=fbf138952d6c1115ba7d797cf7d56f6935184e3f
BUG: memory leak
unreferenced object 0xffff88810a980800 (size 240):
  comm "kworker/1:1", pid 24, jiffies 4294947427 (age 16.220s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<ffffffff83b971c6>] __alloc_skb+0x206/0x270 net/core/skbuff.c:552
    [<ffffffff82eb3731>] alloc_skb include/linux/skbuff.h:1270 [inline]
    [<ffffffff82eb3731>] htc_connect_service+0x121/0x230 drivers/net/wireless/ath/ath9k/htc_hst.c:259
    [<ffffffff82ec03a5>] ath9k_htc_connect_svc drivers/net/wireless/ath/ath9k/htc_drv_init.c:137 [inline]
    [<ffffffff82ec03a5>] ath9k_init_htc_services.constprop.0+0xe5/0x390 drivers/net/wireless/ath/ath9k/htc_drv_init.c:157
    [<ffffffff82ec0747>] ath9k_htc_probe_device+0xf7/0x8a0 drivers/net/wireless/ath/ath9k/htc_drv_init.c:959
    [<ffffffff82eb3ef5>] ath9k_htc_hw_init+0x35/0x60 drivers/net/wireless/ath/ath9k/htc_hst.c:521
    [<ffffffff82eb68dd>] ath9k_hif_usb_firmware_cb+0xcd/0x1f0 drivers/net/wireless/ath/ath9k/hif_usb.c:1243
    [<ffffffff82aa835b>] request_firmware_work_func+0x4b/0x90 drivers/base/firmware_loader/main.c:1107
    [<ffffffff8129a35a>] process_one_work+0x2ba/0x5f0 kernel/workqueue.c:2289
    [<ffffffff8129ac7d>] worker_thread+0x5d/0x5b0 kernel/workqueue.c:2436
    [<ffffffff812a4fa9>] kthread+0x129/0x170 kernel/kthread.c:376
    [<ffffffff81002dcf>] ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

Fixes: fb9987d0f748 ("ath9k_htc: Support for AR9271 chipset.")
Reported-and-tested-by: syzbot+b68fbebe56d8362907e8@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Takeshi Misawa <jeantsuru.cumc.mandola@xxxxxxxxx>
---
 drivers/net/wireless/ath/ath9k/htc_hst.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/ath/ath9k/htc_hst.c b/drivers/net/wireless/ath/ath9k/htc_hst.c
index ca05b07a45e6..6878da6d15b4 100644
--- a/drivers/net/wireless/ath/ath9k/htc_hst.c
+++ b/drivers/net/wireless/ath/ath9k/htc_hst.c
@@ -285,7 +285,8 @@ int htc_connect_service(struct htc_target *target,
 	if (!time_left) {
 		dev_err(target->dev, "Service connection timeout for: %d\n",
 			service_connreq->service_id);
-		return -ETIMEDOUT;
+		ret = -ETIMEDOUT;
+		goto err;
 	}
 
 	*conn_rsp_epid = target->conn_rsp_epid;
-- 
2.39.2