diff options
| author | Stanislaw Gruszka <sgruszka@redhat.com> | 2014-02-19 13:15:17 +0100 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2014-04-02 00:58:55 +0100 |
| commit | cf117670cf074367290d5993fe3111ac6d6b1777 (patch) | |
| tree | 9040a8487f30acff5adb691ea121edbf01710282 /drivers | |
| parent | 2968ef3f71236c3bee3f1c1d2f97469642fb1d9f (diff) | |
ath9k: protect tid->sched check
commit 21f8aaee0c62708654988ce092838aa7df4d25d8 upstream.
We check tid->sched without a lock taken on ath_tx_aggr_sleep(). That
is race condition which can result of doing list_del(&tid->list) twice
(second time with poisoned list node) and cause crash like shown below:
[424271.637220] BUG: unable to handle kernel paging request at 00100104
[424271.637328] IP: [<f90fc072>] ath_tx_aggr_sleep+0x62/0xe0 [ath9k]
...
[424271.639953] Call Trace:
[424271.639998] [<f90f6900>] ? ath9k_get_survey+0x110/0x110 [ath9k]
[424271.640083] [<f90f6942>] ath9k_sta_notify+0x42/0x50 [ath9k]
[424271.640177] [<f809cfef>] sta_ps_start+0x8f/0x1c0 [mac80211]
[424271.640258] [<c10f730e>] ? free_compound_page+0x2e/0x40
[424271.640346] [<f809e915>] ieee80211_rx_handlers+0x9d5/0x2340 [mac80211]
[424271.640437] [<c112f048>] ? kmem_cache_free+0x1d8/0x1f0
[424271.640510] [<c1345a84>] ? kfree_skbmem+0x34/0x90
[424271.640578] [<c10fc23c>] ? put_page+0x2c/0x40
[424271.640640] [<c1345a84>] ? kfree_skbmem+0x34/0x90
[424271.640706] [<c1345a84>] ? kfree_skbmem+0x34/0x90
[424271.640787] [<f809dde3>] ? ieee80211_rx_handlers_result+0x73/0x1d0 [mac80211]
[424271.640897] [<f80a07a0>] ieee80211_prepare_and_rx_handle+0x520/0xad0 [mac80211]
[424271.641009] [<f809e22d>] ? ieee80211_rx_handlers+0x2ed/0x2340 [mac80211]
[424271.641104] [<c13846ce>] ? ip_output+0x7e/0xd0
[424271.641182] [<f80a1057>] ieee80211_rx+0x307/0x7c0 [mac80211]
[424271.641266] [<f90fa6ee>] ath_rx_tasklet+0x88e/0xf70 [ath9k]
[424271.641358] [<f80a0f2c>] ? ieee80211_rx+0x1dc/0x7c0 [mac80211]
[424271.641445] [<f90f82db>] ath9k_tasklet+0xcb/0x130 [ath9k]
Bug report:
https://bugzilla.kernel.org/show_bug.cgi?id=70551
Reported-and-tested-by: Max Sydorenko <maxim.stargazer@gmail.com>
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
[bwh: Backported to 3.2:
- Adjust context
- Use spin_unlock_bh() directly]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/net/wireless/ath/ath9k/xmit.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c index 126ed31affe1..2e88af13293e 100644 --- a/drivers/net/wireless/ath/ath9k/xmit.c +++ b/drivers/net/wireless/ath/ath9k/xmit.c @@ -1176,14 +1176,16 @@ void ath_tx_aggr_sleep(struct ieee80211_sta *sta, struct ath_softc *sc, for (tidno = 0, tid = &an->tid[tidno]; tidno < WME_NUM_TID; tidno++, tid++) { - if (!tid->sched) - continue; - ac = tid->ac; txq = ac->txq; spin_lock_bh(&txq->axq_lock); + if (!tid->sched) { + spin_unlock_bh(&txq->axq_lock); + continue; + } + buffered = !skb_queue_empty(&tid->buf_q); tid->sched = false; |