There is a possible race between USB suspend and main thread:

1. After processing the command response, main thread will submit
rx_cmd URB back so as to process next command response, by
calling mwifiex_usb_submit_rx_urb.

2. During USB suspend, the suspend handler will check if rx_cmd
URB is pending(submitted) and if true, kill this URB.

There is a possible race between #1 and #2, where rx_cmd URB will
be submitted by main thread(#1) after the suspend handler check
in #2.

To fix this, check if device is already suspended in
mwifiex_usb_submit_rx_urb, in which case do not submit the URB.

Signed-off-by: Vidya Dharmaraju <[email protected]>
Signed-off-by: Cathy Luo <[email protected]>
Signed-off-by: Ganapathi Bhat <[email protected]>
---
 drivers/net/wireless/marvell/mwifiex/usb.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/net/wireless/marvell/mwifiex/usb.c 
b/drivers/net/wireless/marvell/mwifiex/usb.c
index 433c6a16..76d80fd 100644
--- a/drivers/net/wireless/marvell/mwifiex/usb.c
+++ b/drivers/net/wireless/marvell/mwifiex/usb.c
@@ -298,6 +298,13 @@ static int mwifiex_usb_submit_rx_urb(struct urb_context 
*ctx, int size)
        struct mwifiex_adapter *adapter = ctx->adapter;
        struct usb_card_rec *card = (struct usb_card_rec *)adapter->card;
 
+       if (test_bit(MWIFIEX_IS_SUSPENDED, &adapter->work_flags)) {
+               mwifiex_dbg(adapter, ERROR,
+                           "%s: card removed/suspended, EP %d rx_cmd URB 
submit skipped\n",
+                           __func__, ctx->ep);
+               return -1;
+       }
+
        if (card->rx_cmd_ep != ctx->ep) {
                ctx->skb = dev_alloc_skb(size);
                if (!ctx->skb) {
-- 
1.9.1

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