Patch "brcmfmac: Make skb header writable before use" has been added to the 3.18-stable tree

This is a note to let you know that I've just added the patch titled

brcmfmac: Make skb header writable before use

to the 3.18-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
brcmfmac-make-skb-header-writable-before-use.patch
and it can be found in the queue-3.18 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: James Hughes <[email protected]>
Date: Tue, 25 Apr 2017 10:15:06 +0100
Subject: brcmfmac: Make skb header writable before use

From: James Hughes <[email protected]>

commit 9cc4b7cb86cbcc6330a3faa8cd65268cd2d3c227 upstream.

The driver was making changes to the skb_header without ensuring it was writable (i.e. uncloned).
This patch also removes some boiler plate header size checking/adjustment code as that is also handled by the skb_cow_header function used to make header writable.

---
 drivers/net/wireless/brcm80211/brcmfmac/dhd_linux.c |   19 +++++--------------
 1 file changed, 5 insertions(+), 14 deletions(-)

@@ -213,22 +213,13 @@ static netdev_tx_t brcmf_netdev_start_xm
 		goto done;
 	}
 
-	/* Make sure there's enough room for any header */
-	if (skb_headroom(skb) < drvr->hdrlen) {
-		struct sk_buff *skb2;
-
-		brcmf_dbg(INFO, "%s: insufficient headroom\n",
+	/* Make sure there's enough writable headroom*/
+	ret = skb_cow_head(skb, drvr->hdrlen);
+	if (ret < 0) {
+		brcmf_err("%s: skb_cow_head failed\n",
 			  brcmf_ifname(drvr, ifp->bssidx));
-		drvr->bus_if->tx_realloc++;
-		skb2 = skb_realloc_headroom(skb, drvr->hdrlen);
 		dev_kfree_skb(skb);
-		skb = skb2;
-		if (skb == NULL) {
-			brcmf_err("%s: skb_realloc_headroom failed\n",
-				  brcmf_ifname(drvr, ifp->bssidx));
-			ret = -ENOMEM;
-			goto done;
-		}
+		goto done;
 	}
 
 	/* validate length for ether packet */

Patches currently in stable-queue which might be from [email protected] are

queue-3.18/brcmfmac-make-skb-header-writable-before-use.patch queue-3.18/brcmfmac-ensure-pointer-correctly-set-if-skb-data-location-changes.patch