This is a note to let you know that I've just added the patch titled
ath9k: fix an invalid pointer dereference in ath9k_rng_stop()
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ath9k-fix-an-invalid-pointer-dereference-in-ath9k_rng_stop.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 07246c115801c27652700e3679bb58661ef7ed65 Mon Sep 17 00:00:00 2001
From: Miaoqing Pan <miaoqing@xxxxxxxxxxxxxx>
Date: Tue, 27 Jun 2017 17:31:53 +0300
Subject: ath9k: fix an invalid pointer dereference in ath9k_rng_stop()
From: Miaoqing Pan <miaoqing@xxxxxxxxxxxxxx>
commit 07246c115801c27652700e3679bb58661ef7ed65 upstream.
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@xxxxxxxxx>
Tested-by: Giulio Genovese <giulio.genovese@xxxxxxxxx>
Signed-off-by: Miaoqing Pan <miaoqing@xxxxxxxxxxxxxx>
Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/wireless/ath/ath9k/rng.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- 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 *s
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;
+ }
}
Patches currently in stable-queue which might be from miaoqing@xxxxxxxxxxxxxx are
queue-4.9/ath9k-fix-an-invalid-pointer-dereference-in-ath9k_rng_stop.patch
queue-4.9/ath9k-fix-tx99-use-after-free.patch
queue-4.9/ath9k-fix-tx99-bus-error.patch