This is a note to let you know that I've just added the patch titled
mISDN: hfcmulti: don't call dev_kfree_skb/kfree_skb() under spin_lock_irqsave()
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
misdn-hfcmulti-don-t-call-dev_kfree_skb-kfree_skb-un.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 8b01dd073459a879e948816ac0b59f3abae9ee78
Author: Yang Yingliang <yangyingliang@xxxxxxxxxx>
Date: Mon Dec 12 16:41:39 2022 +0800
mISDN: hfcmulti: don't call dev_kfree_skb/kfree_skb() under spin_lock_irqsave()
[ Upstream commit 1232946cf522b8de9e398828bde325d7c41f29dd ]
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 <yangyingliang@xxxxxxxxxx>
Reviewed-by: Alexander Duyck <alexanderduyck@xxxxxx>
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/isdn/hardware/mISDN/hfcmulti.c b/drivers/isdn/hardware/mISDN/hfcmulti.c
index df01018acff1..cb86b9bd5c7c 100644
--- a/drivers/isdn/hardware/mISDN/hfcmulti.c
+++ b/drivers/isdn/hardware/mISDN/hfcmulti.c
@@ -3233,6 +3233,7 @@ 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) {
@@ -3261,6 +3262,7 @@ 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) {
@@ -3280,20 +3282,21 @@ 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);
@@ -3400,6 +3403,9 @@ 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
@@ -3421,14 +3427,14 @@ 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);
@@ -3440,6 +3446,7 @@ 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;
