net: b44: set pause params only when interface is up

Hi,

This patch fixes a kernel panic when using netifd.

Kind regards,

           Peter

b44_free_rings() accesses b44::rx_buffers (and ::tx_buffers) unconditionally, but b44::rx_buffers is only valid when the device is up (they get allocated in b44_open(), and deallocated again in b44_close()), any other time these is just a NULL pointers.

So if you try to change the pause params while the network interface is disabled/administratively down, everything explodes (which likely netifd tries to do).

---
 drivers/net/ethernet/broadcom/b44.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

index 3e4fb3c3e834..1be6d14030bc 100644
@@ -2009,12 +2009,14 @@ static int b44_set_pauseparam(struct net_device *dev,
 		bp->flags |= B44_FLAG_TX_PAUSE;
 	else
 		bp->flags &= ~B44_FLAG_TX_PAUSE;
-	if (bp->flags & B44_FLAG_PAUSE_AUTO) {
-		b44_halt(bp);
-		b44_init_rings(bp);
-		b44_init_hw(bp, B44_FULL_RESET);
-	} else {
-		__b44_set_flow_ctrl(bp, bp->flags);
+	if (netif_running(dev)) {
+		if (bp->flags & B44_FLAG_PAUSE_AUTO) {
+			b44_halt(bp);
+			b44_init_rings(bp);
+			b44_init_hw(bp, B44_FULL_RESET);
+		} else {
+			__b44_set_flow_ctrl(bp, bp->flags);
+		}
 	}
 	spin_unlock_irq(&bp->lock);
 

2.35.3

Still above the --- . Don't use attachments.

The best way to send patches is

git format-patch

followed by

git send email

https://docs.kernel.org/process/submitting-patches.html#the-canonical-patch-format

Alternatively, look at b4:

https://b4.docs.kernel.org/en/latest/contributor/prep.html

Interestingly, patchwork does seemed to of extracted the patch:

https://patchwork.kernel.org/project/netdevbpf/patch/[email protected]/

So it could be the patch can be applied as it is. Lets see what Jakub says.

Anyway:

We are picky about things like this because there are a lot of patches flying around, and we need to be efficient at applying them. So we want patches in a specific format. It takes a little bit of time to learn to do it correct, but once you use the tools correctly it becomes simple as a developer and efficient for those receiving the patches.

Andrew

Ah, ok, sorry.

Ok, so I should wait before sending v4?

Another line to attach to the patch for v4?

No problem, I fully understand.

           Peter