From 1232946cf522b8de9e398828bde325d7c41f29dd Mon Sep 17 00:00:00 2001 From: Yang Yingliang Date: Mon, 12 Dec 2022 16:41:39 +0800 Subject: [PATCH] mISDN: hfcmulti: don't call dev_kfree_skb/kfree_skb() under spin_lock_irqsave() It is not allowed to call kfree_skb() or consume_skb() from hardware interrupt context or with hardware interrupts being disabled. skb_queue_purge() is called under spin_lock_irqsave() in handle_dmsg() and hfcm_l1callback(), kfree_skb() is called in them, 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. Fixes: af69fb3a8ffa ("Add mISDN HFC multiport driver") Signed-off-by: Yang Yingliang Reviewed-by: Alexander Duyck Signed-off-by: Jakub Kicinski --- drivers/isdn/hardware/mISDN/hfcmulti.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) diff --git a/drivers/isdn/hardware/mISDN/hfcmulti.c b/drivers/isdn/hardware/mISDN/hfcmulti.c index 4f7eaa17fb27..e840609c50eb 100644 --- a/drivers/isdn/hardware/mISDN/hfcmulti.c +++ b/drivers/isdn/hardware/mISDN/hfcmulti.c @@ -3217,6 +3217,7 @@ static int hfcm_l1callback(struct dchannel *dch, u_int cmd) { struct hfc_multi *hc = dch->hw; + struct sk_buff_head free_queue; u_long flags; switch (cmd) { @@ -3245,6 +3246,7 @@ hfcm_l1callback(struct dchannel *dch, u_int cmd) l1_event(dch->l1, HW_POWERUP_IND); break; case HW_DEACT_REQ: + __skb_queue_head_init(&free_queue); /* start deactivation */ spin_lock_irqsave(&hc->lock, flags); if (hc->ctype == HFC_TYPE_E1) { @@ -3264,20 +3266,21 @@ hfcm_l1callback(struct dchannel *dch, u_int cmd) plxsd_checksync(hc, 0); } } - skb_queue_purge(&dch->squeue); + skb_queue_splice_init(&dch->squeue, &free_queue); if (dch->tx_skb) { - dev_kfree_skb(dch->tx_skb); + __skb_queue_tail(&free_queue, dch->tx_skb); dch->tx_skb = NULL; } dch->tx_idx = 0; if (dch->rx_skb) { - dev_kfree_skb(dch->rx_skb); + __skb_queue_tail(&free_queue, dch->rx_skb); dch->rx_skb = NULL; } test_and_clear_bit(FLG_TX_BUSY, &dch->Flags); if (test_and_clear_bit(FLG_BUSY_TIMER, &dch->Flags)) del_timer(&dch->timer); spin_unlock_irqrestore(&hc->lock, flags); + __skb_queue_purge(&free_queue); break; case HW_POWERUP_REQ: spin_lock_irqsave(&hc->lock, flags); @@ -3384,6 +3387,9 @@ handle_dmsg(struct mISDNchannel *ch, struct sk_buff *skb) case PH_DEACTIVATE_REQ: test_and_clear_bit(FLG_L2_ACTIVATED, &dch->Flags); if (dch->dev.D.protocol != ISDN_P_TE_S0) { + struct sk_buff_head free_queue; + + __skb_queue_head_init(&free_queue); spin_lock_irqsave(&hc->lock, flags); if (debug & DEBUG_HFCMULTI_MSG) printk(KERN_DEBUG @@ -3405,14 +3411,14 @@ handle_dmsg(struct mISDNchannel *ch, struct sk_buff *skb) /* deactivate */ dch->state = 1; } - skb_queue_purge(&dch->squeue); + skb_queue_splice_init(&dch->squeue, &free_queue); if (dch->tx_skb) { - dev_kfree_skb(dch->tx_skb); + __skb_queue_tail(&free_queue, dch->tx_skb); dch->tx_skb = NULL; } dch->tx_idx = 0; if (dch->rx_skb) { - dev_kfree_skb(dch->rx_skb); + __skb_queue_tail(&free_queue, dch->rx_skb); dch->rx_skb = NULL; } test_and_clear_bit(FLG_TX_BUSY, &dch->Flags); @@ -3424,6 +3430,7 @@ handle_dmsg(struct mISDNchannel *ch, struct sk_buff *skb) #endif ret = 0; spin_unlock_irqrestore(&hc->lock, flags); + __skb_queue_purge(&free_queue); } else ret = l1_event(dch->l1, hh->prim); break;