[ 3.8.y.z extended stable ] Patch "net: mac802154: comparision issue of type cast, finding by" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    net: mac802154: comparision issue of type cast, finding by

to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.8.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From db394652eee958a867e5ecfcb2301d76cab538b4 Mon Sep 17 00:00:00 2001
From: Chen Gang <gang.chen at asianux.com>
Date: Thu, 25 Apr 2013 00:49:55 +0000
Subject: net: mac802154: comparision issue of type cast, finding by
 EXTRA_CFLAGS=-W

[ Upstream commit 2c1bbbffa0b644fab4f91878cde0c2e8f52e2dcc ]

Change MAC802154_CHAN_NONE from ~(u8)0 to 0xff, or the comparison in
mac802154_wpan_xmit() for ``chan == MAC802154_CHAN_NONE'' will not
succeed.

This bug can be boiled down to ``u8 foo = 0xff; if (foo == ~(u8)0)
[...] else [...]'' where the condition will always take the else
branch.

Signed-off-by: Chen Gang <gang.chen at asianux.com>
Signed-off-by: David S. Miller <davem at davemloft.net>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 net/mac802154/mac802154.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/mac802154/mac802154.h b/net/mac802154/mac802154.h
index a4dcaf1..703c121 100644
--- a/net/mac802154/mac802154.h
+++ b/net/mac802154/mac802154.h
@@ -90,7 +90,7 @@ struct mac802154_sub_if_data {

 #define MAC802154_MAX_XMIT_ATTEMPTS	3

-#define MAC802154_CHAN_NONE		(~(u8)0) /* No channel is assigned */
+#define MAC802154_CHAN_NONE		0xff /* No channel is assigned */

 extern struct ieee802154_reduced_mlme_ops mac802154_mlme_reduced;
 extern struct ieee802154_mlme_ops mac802154_mlme_wpan;
--
1.8.1.2