Patch "brcmfmac: fix possible buffer overflow in brcmf_cfg80211_mgmt_tx()" has been added to the 3.18-stable tree

[<gregkh@linuxfoundation.org>]

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

    brcmfmac: fix possible buffer overflow in brcmf_cfg80211_mgmt_tx()

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-fix-possible-buffer-overflow-in-brcmf_cfg80211_mgmt_tx.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 <stable@vger.kernel.org> know about it.


>From 8f44c9a41386729fea410e688959ddaa9d51be7c Mon Sep 17 00:00:00 2001
From: Arend van Spriel <arend.vanspriel@broadcom.com>
Date: Fri, 7 Jul 2017 21:09:06 +0100
Subject: brcmfmac: fix possible buffer overflow in brcmf_cfg80211_mgmt_tx()
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

From: Arend van Spriel <arend.vanspriel@broadcom.com>

commit 8f44c9a41386729fea410e688959ddaa9d51be7c upstream.

The lower level nl80211 code in cfg80211 ensures that "len" is between
25 and NL80211_ATTR_FRAME (2304).  We subtract DOT11_MGMT_HDR_LEN (24) from
"len" so thats's max of 2280.  However, the action_frame->data[] buffer is
only BRCMF_FIL_ACTION_FRAME_SIZE (1800) bytes long so this memcpy() can
overflow.

	memcpy(action_frame->data, &buf[DOT11_MGMT_HDR_LEN],
	       le16_to_cpu(action_frame->len));

Fixes: 18e2f61db3b70 ("brcmfmac: P2P action frame tx.")
Reported-by: "freenerguo(郭大兴)" <freenerguo@tencent.com>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/net/wireless/brcm80211/brcmfmac/wl_cfg80211.c |    5 +++++
 1 file changed, 5 insertions(+)

--- a/drivers/net/wireless/brcm80211/brcmfmac/wl_cfg80211.c
+++ b/drivers/net/wireless/brcm80211/brcmfmac/wl_cfg80211.c
@@ -4108,6 +4108,11 @@ brcmf_cfg80211_mgmt_tx(struct wiphy *wip
 		cfg80211_mgmt_tx_status(wdev, *cookie, buf, len, true,
 					GFP_KERNEL);
 	} else if (ieee80211_is_action(mgmt->frame_control)) {
+		if (len > BRCMF_FIL_ACTION_FRAME_SIZE + DOT11_MGMT_HDR_LEN) {
+			brcmf_err("invalid action frame length\n");
+			err = -EINVAL;
+			goto exit;
+		}
 		af_params = kzalloc(sizeof(*af_params), GFP_KERNEL);
 		if (af_params == NULL) {
 			brcmf_err("unable to allocate frame\n");


Patches currently in stable-queue which might be from arend.vanspriel@broadcom.com are

queue-3.18/brcmfmac-fix-possible-buffer-overflow-in-brcmf_cfg80211_mgmt_tx.patch