From: Jiri Kosina <jikos@kernel.org>
To: Johannes Berg <johannes@sipsolutions.net>
Cc: linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org,
Ping-Ke Shih <pkshih@realtek.com>
Subject: [PATCH] rtw89: fix RCU usage in rtw89_core_txq_push() (was Re: [PATCH] mac80211: fix RCU usage in ieee80211_tx_h_select_key())
Date: Tue, 15 Feb 2022 17:11:11 +0100 (CET) [thread overview]
Message-ID: <nycvar.YFH.7.76.2202151700540.11721@cbobk.fhfr.pm> (raw)
In-Reply-To: <af6abf72593074c007fe42205e941dabfd08bf3a.camel@sipsolutions.net>
On Tue, 15 Feb 2022, Johannes Berg wrote:
> >
> > ieee80211_tx_h_select_key() is performing a series of RCU dereferences,
> > but none of the callers seems to be taking RCU read-side lock; let's
> > acquire the lock in ieee80211_tx_h_select_key() itself.
> >
> but but ...
>
> > ieee80211_tx_dequeue+0x1a7/0x1260 [mac80211 911c23e2351c0ae60b597a67b1204a5ea955e365]
> > rtw89_core_txq_work+0x1a6/0x420 [rtw89_core b39ba493f2e517ad75e0f8187ecc24edf58bbbea]
>
> /**
> * ieee80211_tx_dequeue - dequeue a packet from a software tx queue
> *
> * @hw: pointer as obtained from ieee80211_alloc_hw()
> * @txq: pointer obtained from station or virtual interface, or from
> * ieee80211_next_txq()
> *
> * Returns the skb if successful, %NULL if no frame was available.
> *
> * Note that this must be called in an rcu_read_lock() critical section,
> * which can only be released after the SKB was handled. Some pointers in
> [...]
>
> -> driver bug?
Right you are, thanks.
CCing Ping-Ke Shih; find updated fix below.
From: Jiri Kosina <jkosina@suse.cz>
Subject: [PATCH] rtw89: fix RCU usage in rtw89_core_txq_push()
ieee80211_tx_h_select_key() is performing a series of RCU dereferences,
but rtw89_core_txq_push() is calling it (via ieee80211_tx_dequeue_ni())
without RCU read-side lock held; fix that.
This addresses the splat below.
=============================
WARNING: suspicious RCU usage
5.17.0-rc4-00003-gccad664b7f14 #3 Tainted: G E
-----------------------------
net/mac80211/tx.c:593 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
2 locks held by kworker/u33:0/184:
#0: ffff9c0b14811d38 ((wq_completion)rtw89_tx_wq){+.+.}-{0:0}, at: process_one_work+0x258/0x660
#1: ffffb97380cf3e78 ((work_completion)(&rtwdev->txq_work)){+.+.}-{0:0}, at: process_one_work+0x258/0x660
stack backtrace:
CPU: 8 PID: 184 Comm: kworker/u33:0 Tainted: G E 5.17.0-rc4-00003-gccad664b7f14 #3 473b49ab0e7c2d6af2900c756bfd04efd7a9de13
Hardware name: LENOVO 20UJS2B905/20UJS2B905, BIOS R1CET63W(1.32 ) 04/09/2021
Workqueue: rtw89_tx_wq rtw89_core_txq_work [rtw89_core]
Call Trace:
<TASK>
dump_stack_lvl+0x58/0x71
ieee80211_tx_h_select_key+0x2c0/0x530 [mac80211 911c23e2351c0ae60b597a67b1204a5ea955e365]
ieee80211_tx_dequeue+0x1a7/0x1260 [mac80211 911c23e2351c0ae60b597a67b1204a5ea955e365]
rtw89_core_txq_work+0x1a6/0x420 [rtw89_core b39ba493f2e517ad75e0f8187ecc24edf58bbbea]
process_one_work+0x2d8/0x660
worker_thread+0x39/0x3e0
? process_one_work+0x660/0x660
kthread+0xe5/0x110
? kthread_complete_and_exit+0x20/0x20
ret_from_fork+0x22/0x30
</TASK>
=============================
WARNING: suspicious RCU usage
5.17.0-rc4-00003-gccad664b7f14 #3 Tainted: G E
-----------------------------
net/mac80211/tx.c:607 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
2 locks held by kworker/u33:0/184:
#0: ffff9c0b14811d38 ((wq_completion)rtw89_tx_wq){+.+.}-{0:0}, at: process_one_work+0x258/0x660
#1: ffffb97380cf3e78 ((work_completion)(&rtwdev->txq_work)){+.+.}-{0:0}, at: process_one_work+0x258/0x660
stack backtrace:
CPU: 8 PID: 184 Comm: kworker/u33:0 Tainted: G E 5.17.0-rc4-00003-gccad664b7f14 #3 473b49ab0e7c2d6af2900c756bfd04efd7a9de13
Hardware name: LENOVO 20UJS2B905/20UJS2B905, BIOS R1CET63W(1.32 ) 04/09/2021
Workqueue: rtw89_tx_wq rtw89_core_txq_work [rtw89_core]
Call Trace:
<TASK>
dump_stack_lvl+0x58/0x71
ieee80211_tx_h_select_key+0x464/0x530 [mac80211 911c23e2351c0ae60b597a67b1204a5ea955e365]
ieee80211_tx_dequeue+0x1a7/0x1260 [mac80211 911c23e2351c0ae60b597a67b1204a5ea955e365]
rtw89_core_txq_work+0x1a6/0x420 [rtw89_core b39ba493f2e517ad75e0f8187ecc24edf58bbbea]
process_one_work+0x2d8/0x660
worker_thread+0x39/0x3e0
? process_one_work+0x660/0x660
kthread+0xe5/0x110
? kthread_complete_and_exit+0x20/0x20
ret_from_fork+0x22/0x30
</TASK>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
---
drivers/net/wireless/realtek/rtw89/core.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/net/wireless/realtek/rtw89/core.c b/drivers/net/wireless/realtek/rtw89/core.c
index a0737eea9f81..9632e7f218dd 100644
--- a/drivers/net/wireless/realtek/rtw89/core.c
+++ b/drivers/net/wireless/realtek/rtw89/core.c
@@ -1509,11 +1509,12 @@ static void rtw89_core_txq_push(struct rtw89_dev *rtwdev,
unsigned long i;
int ret;
+ rcu_read_lock();
for (i = 0; i < frame_cnt; i++) {
skb = ieee80211_tx_dequeue_ni(rtwdev->hw, txq);
if (!skb) {
rtw89_debug(rtwdev, RTW89_DBG_TXRX, "dequeue a NULL skb\n");
- return;
+ goto out;
}
rtw89_core_txq_check_agg(rtwdev, rtwtxq, skb);
ret = rtw89_core_tx_write(rtwdev, vif, sta, skb, NULL);
@@ -1523,6 +1524,8 @@ static void rtw89_core_txq_push(struct rtw89_dev *rtwdev,
break;
}
}
+out:
+ rcu_read_unlock();
}
static u32 rtw89_check_and_reclaim_tx_resource(struct rtw89_dev *rtwdev, u8 tid)
--
Jiri Kosina
SUSE Labs
next prev parent reply other threads:[~2022-02-15 16:11 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-15 15:47 [PATCH] mac80211: fix RCU usage in ieee80211_tx_h_select_key() Jiri Kosina
2022-02-15 15:50 ` Johannes Berg
2022-02-15 16:11 ` Jiri Kosina [this message]
2022-02-15 17:27 ` [PATCH] rtw89: fix RCU usage in rtw89_core_txq_push() (was Re: [PATCH] mac80211: fix RCU usage in ieee80211_tx_h_select_key()) Kalle Valo
2022-02-16 15:27 ` Jiri Kosina
2022-02-15 21:06 ` [PATCH] mac80211: fix RCU usage in ieee80211_tx_h_select_key() kernel test robot
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=nycvar.YFH.7.76.2202151700540.11721@cbobk.fhfr.pm \
--to=jikos@kernel.org \
--cc=johannes@sipsolutions.net \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-wireless@vger.kernel.org \
--cc=pkshih@realtek.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).