From bd5dac7ced5a7c9faa4dc468ac9560c3256df845 Mon Sep 17 00:00:00 2001
From: Lorenzo Bianconi <lorenzo@kernel.org>
Date: Thu, 13 Oct 2022 21:07:37 +0200
Subject: [PATCH] wifi: mt76: do not run mt76u_status_worker if the device is not running
Git-commit: bd5dac7ced5a7c9faa4dc468ac9560c3256df845
Patch-mainline: v6.2-rc1
References: git-fixes
Fix the following NULL pointer dereference avoiding to run
mt76u_status_worker thread if the device is not running yet.
Kasan: null-ptr-deref in range
[0x0000000000000000-0x0000000000000007]
Cpu: 0 PID: 98 Comm: kworker/u2:2 Not tainted 5.14.0+ #78 Hardware
Name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
Workqueue: mt76 mt76u_tx_status_data
Rip: 0010:mt76x02_mac_fill_tx_status.isra.0+0x82c/0x9e0
Code: c5 48 b8 00 00 00 00 00 fc ff df 80 3c 02 00 0f 85 94 01 00 00
48 b8 00 00 00 00 00 fc ff df 4d 8b 34 24 4c 89 f2 48 c1 ea 03 <0f>
b6
04 02 84 c0 74 08 3c 03 0f 8e 89 01 00 00 41 8b 16 41 0f b7
Rsp: 0018:ffffc900005af988 EFLAGS: 00010246
Rax: dffffc0000000000 RBX: ffffc900005afae8 RCX: 0000000000000000
Rdx: 0000000000000000 RSI: ffffffff832fc661 RDI: ffffc900005afc2a
Rbp: ffffc900005afae0 R08: 0000000000000001 R09: fffff520000b5f3c
R10: 0000000000000003 R11: fffff520000b5f3b R12: ffff88810b6132d8
R13: 000000000000ffff R14: 0000000000000000 R15: ffffc900005afc28
Fs: 0000000000000000(0000) GS:ffff88811aa00000(0000)
knlGS:0000000000000000
Cs: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Cr2: 00007fa0eda6a000 CR3: 0000000118f17000 CR4: 0000000000750ef0
Pkru: 55555554
Call Trace:
mt76x02_send_tx_status+0x1d2/0xeb0
mt76x02_tx_status_data+0x8e/0xd0
mt76u_tx_status_data+0xe1/0x240
process_one_work+0x92b/0x1460
worker_thread+0x95/0xe00
kthread+0x3a1/0x480
ret_from_fork+0x1f/0x30
Modules linked in:
--[ end trace 8df5d20fc5040f65 ]--
48 b8 00 00 00 00 00 fc ff df 4d 8b 34 24 4c 89 f2 48 c1 ea 03 <0f>
b6
04 02 84 c0 74 08 3c 03 0f 8e 89 01 00 00 41 8b 16 41 0f b7
knlGS:0000000000000000
Moreover move stat_work schedule out of the for loop.
Reported-by: Dokyung Song <dokyungs@yonsei.ac.kr>
Co-developed-by: Deren Wu <deren.wu@mediatek.com>
Signed-off-by: Deren Wu <deren.wu@mediatek.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/net/wireless/mediatek/mt76/usb.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/drivers/net/wireless/mediatek/mt76/usb.c b/drivers/net/wireless/mediatek/mt76/usb.c
index 4c4033bb1bb3..0597df2729a6 100644
--- a/drivers/net/wireless/mediatek/mt76/usb.c
+++ b/drivers/net/wireless/mediatek/mt76/usb.c
@@ -766,6 +766,9 @@ static void mt76u_status_worker(struct mt76_worker *w)
struct mt76_queue *q;
int i;
+ if (!test_bit(MT76_STATE_RUNNING, &dev->phy.state))
+ return;
+
for (i = 0; i < IEEE80211_NUM_ACS; i++) {
q = dev->phy.q_tx[i];
if (!q)
@@ -785,11 +788,11 @@ static void mt76u_status_worker(struct mt76_worker *w)
wake_up(&dev->tx_wait);
mt76_worker_schedule(&dev->tx_worker);
-
- if (dev->drv->tx_status_data &&
- !test_and_set_bit(MT76_READING_STATS, &dev->phy.state))
- queue_work(dev->wq, &dev->usb.stat_work);
}
+
+ if (dev->drv->tx_status_data &&
+ !test_and_set_bit(MT76_READING_STATS, &dev->phy.state))
+ queue_work(dev->wq, &dev->usb.stat_work);
}
static void mt76u_tx_status_data(struct work_struct *work)
--
2.35.3