mISDN: hfcsusb: don't call dev_kfree_skb/kfree_skb() under spin_lock_irqsave()
authorYang Yingliang <yangyingliang@huawei.com>
Mon, 12 Dec 2022 08:41:37 +0000 (16:41 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 31 Dec 2022 12:32:53 +0000 (13:32 +0100)
commit793f872866d678c95500d5bbac57cb6f3b1ea819
tree3db9cf4d71315b578c4ec7c24b9eed1406eaac77
parentb316841b6bdccf66f2a6729074dc712b8016bb32
mISDN: hfcsusb: don't call dev_kfree_skb/kfree_skb() under spin_lock_irqsave()

[ Upstream commit ddc9648db162eee556edd5222d2808fe33730203 ]

It is not allowed to call kfree_skb() or consume_skb() from hardware
interrupt context or with hardware interrupts being disabled.

It should use dev_kfree_skb_irq() or dev_consume_skb_irq() instead.
The difference between them is free reason, dev_kfree_skb_irq() means
the SKB is dropped in error and dev_consume_skb_irq() means the SKB
is consumed in normal.

skb_queue_purge() is called under spin_lock_irqsave() in hfcusb_l2l1D(),
kfree_skb() is called in it, to fix this, use skb_queue_splice_init()
to move the dch->squeue to a free queue, also enqueue the tx_skb and
rx_skb, at last calling __skb_queue_purge() to free the SKBs afer unlock.

In tx_iso_complete(), dev_kfree_skb() is called to consume the transmitted
SKB, so replace it with dev_consume_skb_irq().

Fixes: 69f52adb2d53 ("mISDN: Add HFC USB driver")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/isdn/hardware/mISDN/hfcsusb.c