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From:   Chi-Hsien Lin <chi-hsien.lin@cypress.com>
To:     linux-wireless@vger.kernel.org
Cc:     brcm80211-dev-list@broadcom.com, brcm80211-dev-list@cypress.com,
        Arend van Spriel <arend.vanspriel@broadcom.com>,
        Franky Lin <franky.lin@broadcom.com>,
        Hante Meuleman <hante.meuleman@broadcom.com>,
        Wright Feng <wright.feng@cypress.com>,
        Kalle Valo <kvalo@codeaurora.org>,
        Raveendran Somu <raveendran.somu@cypress.com>,
        Chi-hsien Lin <chi-hsien.lin@cypress.com>
Subject: [PATCH 2/6] brcmfmac: Fix double freeing in the fmac usb data path
Date:   Thu, 13 Feb 2020 02:44:32 -0600
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From: Raveendran Somu <raveendran.somu@cypress.com>

When the brcmf_fws_process_skb() fails to get hanger slot for
queuing the skb, it tries to free the skb.
But the caller brcmf_netdev_start_xmit() of that funciton frees
the packet on error return value.
This causes the double freeing and which caused the kernel crash.

Signed-off-by: Raveendran Somu <raveendran.somu@cypress.com>
Signed-off-by: Chi-hsien Lin <chi-hsien.lin@cypress.com>
---
 drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.c
index 5e1a11c07551..10022c765354 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.c
@@ -2145,8 +2145,7 @@ int brcmf_fws_process_skb(struct brcmf_if *ifp, struct sk_buff *skb)
 		brcmf_fws_enq(fws, BRCMF_FWS_SKBSTATE_DELAYED, fifo, skb);
 		brcmf_fws_schedule_deq(fws);
 	} else {
-		bphy_err(drvr, "drop skb: no hanger slot\n");
-		brcmf_txfinalize(ifp, skb, false);
+		bphy_err(drvr, "no hanger slot available\n");
 		rc = -ENOMEM;
 	}
 	brcmf_fws_unlock(fws);
-- 
2.1.0