From: Lorenzo Bianconi lorenzo@kernel.org
commit 0acb20a5438c36e0cf2b8bf255f314b59fcca6ef upstream.
The following crash log can occur unplugging the usb dongle since, after the urb poison in mt7601u_free_tx_queue(), usb_submit_urb() will always fail resulting in a skb kfree while the skb has been already queued.
Fix the issue enqueuing the skb only if usb_submit_urb() succeed.
Hardware name: Hewlett-Packard 500-539ng/2B2C, BIOS 80.06 04/01/2015 Workqueue: usb_hub_wq hub_event RIP: 0010:skb_trim+0x2c/0x30 RSP: 0000:ffffb4c88005bba8 EFLAGS: 00010206 RAX: 000000004ad483ee RBX: ffff9a236625dee0 RCX: 000000000000662f RDX: 000000000000000c RSI: 0000000000000000 RDI: ffff9a2343179300 RBP: ffff9a2343179300 R08: 0000000000000001 R09: 0000000000000000 R10: ffff9a23748f7840 R11: 0000000000000001 R12: ffff9a236625e4d4 R13: ffff9a236625dee0 R14: 0000000000001080 R15: 0000000000000008 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd410a34ef8 CR3: 00000001416ee001 CR4: 00000000001706f0 Call Trace: mt7601u_tx_status+0x3e/0xa0 [mt7601u] mt7601u_dma_cleanup+0xca/0x110 [mt7601u] mt7601u_cleanup+0x22/0x30 [mt7601u] mt7601u_disconnect+0x22/0x60 [mt7601u] usb_unbind_interface+0x8a/0x270 ? kernfs_find_ns+0x35/0xd0 __device_release_driver+0x17a/0x230 device_release_driver+0x24/0x30 bus_remove_device+0xdb/0x140 device_del+0x18b/0x430 ? kobject_put+0x98/0x1d0 usb_disable_device+0xc6/0x1f0 usb_disconnect.cold+0x7e/0x20a hub_event+0xbf3/0x1870 process_one_work+0x1b6/0x350 worker_thread+0x53/0x3e0 ? process_one_work+0x350/0x350 kthread+0x11b/0x140 ? __kthread_bind_mask+0x60/0x60 ret_from_fork+0x22/0x30
Fixes: 23377c200b2eb ("mt7601u: fix possible memory leak when the device is disconnected") Signed-off-by: Lorenzo Bianconi lorenzo@kernel.org Acked-by: Jakub Kicinski kubakici@wp.pl Signed-off-by: Kalle Valo kvalo@codeaurora.org Link: https://lore.kernel.org/r/3b85219f669a63a8ced1f43686de05915a580489.161091924... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/net/wireless/mediatek/mt7601u/dma.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/net/wireless/mediatek/mt7601u/dma.c +++ b/drivers/net/wireless/mediatek/mt7601u/dma.c @@ -310,7 +310,6 @@ static int mt7601u_dma_submit_tx(struct }
e = &q->e[q->end]; - e->skb = skb; usb_fill_bulk_urb(e->urb, usb_dev, snd_pipe, skb->data, skb->len, mt7601u_complete_tx, q); ret = usb_submit_urb(e->urb, GFP_ATOMIC); @@ -328,6 +327,7 @@ static int mt7601u_dma_submit_tx(struct
q->end = (q->end + 1) % q->entries; q->used++; + e->skb = skb;
if (q->used >= q->entries) ieee80211_stop_queue(dev->hw, skb_get_queue_mapping(skb));