diff options
author | Miaoqing Pan <miaoqing@codeaurora.org> | 2017-06-27 17:31:53 +0300 |
---|---|---|
committer | Kalle Valo <kvalo@qca.qualcomm.com> | 2017-06-28 19:54:33 +0300 |
commit | 07246c115801c27652700e3679bb58661ef7ed65 (patch) | |
tree | 3dbd702a42f5394a96a507e6b93e66126247e613 /drivers/net/wireless | |
parent | 1cdb6c9fd43366413f928531a03fc07a8c14429a (diff) | |
download | linux-07246c115801c27652700e3679bb58661ef7ed65.tar.xz |
ath9k: fix an invalid pointer dereference in ath9k_rng_stop()
The bug was triggered when do suspend/resuming continuously
on Dell XPS L322X/0PJHXN version 9333 (2013) with kernel
4.12.0-041200rc4-generic. But can't reproduce on DELL
E5440 + AR9300 PCIE chips.
The warning is caused by accessing invalid pointer sc->rng_task.
sc->rng_task is not be cleared after kthread_stop(sc->rng_task)
be called in ath9k_rng_stop(). Because the kthread is stopped
before ath9k_rng_kthread() be scheduled.
So set sc->rng_task to null after kthread_stop(sc->rng_task) to
resolve this issue.
WARNING: CPU: 0 PID: 984 at linux/kernel/kthread.c:71 kthread_stop+0xf1/0x100
CPU: 0 PID: 984 Comm: NetworkManager Not tainted 4.12.0-041200rc4-generic #201706042031
Hardware name: Dell Inc. Dell System XPS L322X/0PJHXN, BIOS A09 05/15/2013
task: ffff950170fdda00 task.stack: ffffa22c01538000
RIP: 0010:kthread_stop+0xf1/0x100
RSP: 0018:ffffa22c0153b5b0 EFLAGS: 00010246
RAX: ffffffffa6257800 RBX: ffff950171b79560 RCX: 0000000000000000
RDX: 0000000080000000 RSI: 000000007fffffff RDI: ffff9500ac9a9680
RBP: ffffa22c0153b5c8 R08: 0000000000000000 R09: 0000000000000000
R10: ffffa22c0153b648 R11: ffff9501768004b8 R12: ffff9500ac9a9680
R13: ffff950171b79f70 R14: ffff950171b78780 R15: ffff9501749dc018
FS: 00007f0d6bfd5540(0000) GS:ffff95017f200000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc190161a08 CR3: 0000000232906000 CR4: 00000000001406f0
Call Trace:
ath9k_rng_stop+0x1a/0x20 [ath9k]
ath9k_stop+0x3b/0x1d0 [ath9k]
drv_stop+0x33/0xf0 [mac80211]
ieee80211_stop_device+0x43/0x50 [mac80211]
ieee80211_do_stop+0x4f2/0x810 [mac80211]
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=196043
Reported-by: Giulio Genovese <giulio.genovese@gmail.com>
Tested-by: Giulio Genovese <giulio.genovese@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Miaoqing Pan <miaoqing@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
Diffstat (limited to 'drivers/net/wireless')
-rw-r--r-- | drivers/net/wireless/ath/ath9k/rng.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/net/wireless/ath/ath9k/rng.c b/drivers/net/wireless/ath/ath9k/rng.c index 568b1c6c2b2b..73f46fb3e83a 100644 --- a/drivers/net/wireless/ath/ath9k/rng.c +++ b/drivers/net/wireless/ath/ath9k/rng.c @@ -120,6 +120,8 @@ void ath9k_rng_start(struct ath_softc *sc) void ath9k_rng_stop(struct ath_softc *sc) { - if (sc->rng_task) + if (sc->rng_task) { kthread_stop(sc->rng_task); + sc->rng_task = NULL; + } } |