Patch "mac80211: move WEP tailroom size check" has been added to the 3.14-stable tree

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

mac80211: move WEP tailroom size check

to the 3.14-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:

     mac80211-move-wep-tailroom-size-check.patch

and it can be found in the queue-3.14 subdirectory.

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

From: Janusz Dziedzic <[email protected]>
Date: Mon, 11 May 2015 11:31:15 +0200
Subject: mac80211: move WEP tailroom size check

From: Janusz Dziedzic <[email protected]>

commit 47b4e1fc4972cc43a19121bc2608a60aef3bf216 upstream.

Remove checking tailroom when adding IV as it uses only headroom, and move the check to the ICV generation that actually needs the tailroom.

In other case I hit such warning and datapath don't work, when testing:
- IBSS + WEP
- ath9k with hw crypt enabled
- IPv6 data (ping6)

WARNING: CPU: 3 PID: 13301 at net/mac80211/wep.c:102 ieee80211_wep_add_iv+0x129/0x190 [mac80211]()
[...]
Call Trace:
[<ffffffff817bf491>] dump_stack+0x45/0x57
[<ffffffff8107746a>] warn_slowpath_common+0x8a/0xc0
[<ffffffff8107755a>] warn_slowpath_null+0x1a/0x20
[<ffffffffc09ae109>] ieee80211_wep_add_iv+0x129/0x190 [mac80211]
[<ffffffffc09ae7ab>] ieee80211_crypto_wep_encrypt+0x6b/0xd0 [mac80211]
[<ffffffffc09d3fb1>] invoke_tx_handlers+0xc51/0xf30 [mac80211]

[...]

---
 net/mac80211/wep.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

@@ -98,8 +98,7 @@ static u8 *ieee80211_wep_add_iv(struct i
 
 	hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
 
-	if (WARN_ON(skb_tailroom(skb) < IEEE80211_WEP_ICV_LEN ||
-		    skb_headroom(skb) < IEEE80211_WEP_IV_LEN))
+	if (WARN_ON(skb_headroom(skb) < IEEE80211_WEP_IV_LEN))
 		return NULL;
 
 	hdrlen = ieee80211_hdrlen(hdr->frame_control);

@@ -169,6 +168,9 @@ int ieee80211_wep_encrypt(struct ieee802
 	size_t len;
 	u8 rc4key[3 + WLAN_KEY_LEN_WEP104];
 
+	if (WARN_ON(skb_tailroom(skb) < IEEE80211_WEP_ICV_LEN))
+		return -1;
+
 	iv = ieee80211_wep_add_iv(local, skb, keylen, keyidx);
 	if (!iv)
 		return -1;

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

queue-3.14/mac80211-move-wep-tailroom-size-check.patch