From: Johannes Berg <johannes@sipsolutions.net>
To: John Linville <linville@tuxdriver.com>
Cc: linux-wireless <linux-wireless@vger.kernel.org>
Subject: [PATCH] mac80211: fix sta assignment
Date: Thu, 22 Jul 2010 17:11:28 +0200 [thread overview]
Message-ID: <1279811488.12439.22.camel@jlt3.sipsolutions.net> (raw)
From: Johannes Berg <johannes.berg@intel.com>
I just had the following:
WARNING: at drivers/net/wireless/iwlwifi/iwl-agn-tx.c:574 iwlagn_tx_skb+0x1576/0x15f0 [iwlagn]()
Call Trace:
<IRQ> [<ffffffff8105c5df>] warn_slowpath_common+0x7f/0xc0
[<ffffffff8105c63a>] warn_slowpath_null+0x1a/0x20
[<ffffffffa0290b46>] iwlagn_tx_skb+0x1576/0x15f0 [iwlagn]
[<ffffffffa027076c>] iwl_mac_tx+0x5c/0x260 [iwlagn]
[<ffffffffa01bdf5b>] __ieee80211_tx+0x10b/0x1a0 [mac80211]
[<ffffffffa01bfb86>] ieee80211_tx_pending+0x186/0x2d0 [mac80211]
[<ffffffff81062ea5>] tasklet_action+0x125/0x130
[<ffffffff810634a6>] __do_softirq+0x106/0x270
[<ffffffff8100c09c>] call_softirq+0x1c/0x30
iwlagn 0000:02:00.0: Attempting to modify non-existing station 107
Note that 107 == 0x6b which is slab poison.
The reason is that mac80211 passed a freed station
pointer to mac80211, because as it happened iwlwifi
reset itself while mac80211 was disconnecting from
the network.
It turns out that we do take care to look up the
station pointer in ieee80211_tx_pending_skb, but
then don't use it, which obviously is a bug. Fix
this by removing the ieee80211_tx_h_sta handler
and assigning the station pointer directly.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
net/mac80211/tx.c | 17 +++++------------
1 file changed, 5 insertions(+), 12 deletions(-)
--- wireless-testing.orig/net/mac80211/tx.c 2010-07-22 16:55:47.000000000 +0200
+++ wireless-testing/net/mac80211/tx.c 2010-07-22 16:59:49.000000000 +0200
@@ -576,17 +576,6 @@ ieee80211_tx_h_select_key(struct ieee802
}
static ieee80211_tx_result debug_noinline
-ieee80211_tx_h_sta(struct ieee80211_tx_data *tx)
-{
- struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
-
- if (tx->sta && tx->sta->uploaded)
- info->control.sta = &tx->sta->sta;
-
- return TX_CONTINUE;
-}
-
-static ieee80211_tx_result debug_noinline
ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
{
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
@@ -1307,6 +1296,11 @@ static int __ieee80211_tx(struct ieee802
break;
}
+ if (sta && sta->uploaded)
+ info->control.sta = &sta->sta;
+ else
+ info->control.sta = NULL;
+
ret = drv_tx(local, skb);
if (WARN_ON(ret != NETDEV_TX_OK && skb->len != len)) {
dev_kfree_skb(skb);
@@ -1346,7 +1340,6 @@ static int invoke_tx_handlers(struct iee
CALL_TXH(ieee80211_tx_h_check_assoc);
CALL_TXH(ieee80211_tx_h_ps_buf);
CALL_TXH(ieee80211_tx_h_select_key);
- CALL_TXH(ieee80211_tx_h_sta);
if (!(tx->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL))
CALL_TXH(ieee80211_tx_h_rate_ctrl);
reply other threads:[~2010-07-22 15:11 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1279811488.12439.22.camel@jlt3.sipsolutions.net \
--to=johannes@sipsolutions.net \
--cc=linux-wireless@vger.kernel.org \
--cc=linville@tuxdriver.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).