From: Lorenzo Bianconi lorenzo@kernel.org
[ Upstream commit bd5dac7ced5a7c9faa4dc468ac9560c3256df845 ]
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 ]-- 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
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 Signed-off-by: Sasha Levin sashal@kernel.org --- 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 1e9f60bb811a..b47343e321b8 100644 --- a/drivers/net/wireless/mediatek/mt76/usb.c +++ b/drivers/net/wireless/mediatek/mt76/usb.c @@ -814,6 +814,9 @@ 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) @@ -833,11 +836,11 @@ 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)