linux-kernel - [PATCH 34/81] rtlwifi: Fix scheduling while atomic bug

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1361299784-8830-35-git-send-email-herton.krzesinski@canonical.com>
Date:	Tue, 19 Feb 2013 15:48:57 -0300
From:	Herton Ronaldo Krzesinski <herton.krzesinski@...onical.com>
To:	linux-kernel@...r.kernel.org, stable@...r.kernel.org,
	kernel-team@...ts.ubuntu.com
Cc:	Larry Finger <Larry.Finger@...inger.net>,
	Nathaniel Doherty <ntdoherty@...il.com>,
	Stanislaw Gruszka <sgruszka@...hat.com>,
	"John W. Linville" <linville@...driver.com>,
	Herton Ronaldo Krzesinski <herton.krzesinski@...onical.com>
Subject: [PATCH 34/81] rtlwifi: Fix scheduling while atomic bug

3.5.7.6 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Larry Finger <Larry.Finger@...inger.net>

commit a5ffbe0a1993a27072742ef7db6cf9839956fce9 upstream.

Kernel commits 41affd5 and 6539306 changed the locking in rtl_lps_leave()
from a spinlock to a mutex by doing the calls indirectly from a work queue
to reduce the time that interrupts were disabled. This change was fine for
most systems; however a scheduling while atomic bug was reported in
https://bugzilla.redhat.com/show_bug.cgi?id=903881. The backtrace indicates
that routine rtl_is_special(), which calls rtl_lps_leave() in three places
was entered in atomic context. These direct calls are replaced by putting a
request on the appropriate work queue.

Signed-off-by: Larry Finger <Larry.Finger@...inger.net>
Reported-and-tested-by: Nathaniel Doherty <ntdoherty@...il.com>
Cc: Nathaniel Doherty <ntdoherty@...il.com>
Cc: Stanislaw Gruszka <sgruszka@...hat.com>
Signed-off-by: John W. Linville <linville@...driver.com>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@...onical.com>
---
 drivers/net/wireless/rtlwifi/base.c |    7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/rtlwifi/base.c b/drivers/net/wireless/rtlwifi/base.c
index f4c852c..4110a6d 100644
--- a/drivers/net/wireless/rtlwifi/base.c
+++ b/drivers/net/wireless/rtlwifi/base.c
@@ -980,7 +980,8 @@ u8 rtl_is_special_data(struct ieee80211_hw *hw, struct sk_buff *skb, u8 is_tx)
 					 is_tx ? "Tx" : "Rx");
 
 				if (is_tx) {
-					rtl_lps_leave(hw);
+					schedule_work(&rtlpriv->
+						      works.lps_leave_work);
 					ppsc->last_delaylps_stamp_jiffies =
 					    jiffies;
 				}
@@ -990,7 +991,7 @@ u8 rtl_is_special_data(struct ieee80211_hw *hw, struct sk_buff *skb, u8 is_tx)
 		}
 	} else if (ETH_P_ARP == ether_type) {
 		if (is_tx) {
-			rtl_lps_leave(hw);
+			schedule_work(&rtlpriv->works.lps_leave_work);
 			ppsc->last_delaylps_stamp_jiffies = jiffies;
 		}
 
@@ -1000,7 +1001,7 @@ u8 rtl_is_special_data(struct ieee80211_hw *hw, struct sk_buff *skb, u8 is_tx)
 			 "802.1X %s EAPOL pkt!!\n", is_tx ? "Tx" : "Rx");
 
 		if (is_tx) {
-			rtl_lps_leave(hw);
+			schedule_work(&rtlpriv->works.lps_leave_work);
 			ppsc->last_delaylps_stamp_jiffies = jiffies;
 		}
 
-- 
1.7.9.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/