[PATCH] Bluetooth: hci_event: Remove excessive bluetooth warning

[PATCH] Bluetooth: hci_event: Remove excessive bluetooth warning

[Mike Lothian]

Fixes: 3e54c5890c87a ("Bluetooth: hci_event: Use of a function table to handle HCI events")
Signed-off-by: Mike Lothian <mike@fireburn.co.uk>
---
 net/bluetooth/hci_event.c | 8 --------
 1 file changed, 8 deletions(-)

diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index fc30f4c03d29..aa57fccd2e47 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -6818,14 +6818,6 @@ static void hci_event_func(struct hci_dev *hdev, u8 event, struct sk_buff *skb,
 		return;
 	}
 
-	/* Just warn if the length is over max_len size it still be
-	 * possible to partially parse the event so leave to callback to
-	 * decide if that is acceptable.
-	 */
-	if (skb->len > ev->max_len)
-		bt_dev_warn(hdev, "unexpected event 0x%2.2x length: %u > %u",
-			    event, skb->len, ev->max_len);
-
 	data = hci_ev_skb_pull(hdev, skb, event, ev->min_len);
 	if (!data)
 		return;
-- 
2.35.1

Re: [PATCH] Bluetooth: hci_event: Remove excessive bluetooth warning

[Marcel Holtmann]

Hi Mike,

> Fixes: 3e54c5890c87a ("Bluetooth: hci_event: Use of a function table to handle HCI events")
> Signed-off-by: Mike Lothian <mike@fireburn.co.uk>
> ---
> net/bluetooth/hci_event.c | 8 --------
> 1 file changed, 8 deletions(-)
> 
> diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
> index fc30f4c03d29..aa57fccd2e47 100644
> --- a/net/bluetooth/hci_event.c
> +++ b/net/bluetooth/hci_event.c
> @@ -6818,14 +6818,6 @@ static void hci_event_func(struct hci_dev *hdev, u8 event, struct sk_buff *skb,
> 		return;
> 	}
> 
> -	/* Just warn if the length is over max_len size it still be
> -	 * possible to partially parse the event so leave to callback to
> -	 * decide if that is acceptable.
> -	 */
> -	if (skb->len > ev->max_len)
> -		bt_dev_warn(hdev, "unexpected event 0x%2.2x length: %u > %u",
> -			    event, skb->len, ev->max_len);
> -

which event type is this? You need to have a commit message giving details. I am also pretty sure that this is broken hardware and we can go for ratelimited version, but the warning is justified if the hardware is stupid. If our table is wrong, we fix the table, but not just silence an unpleasant warning.

Regards

Marcel

Re: [PATCH] Bluetooth: hci_event: Remove excessive bluetooth warning

[Mike Lothian]

On Mon, 14 Mar 2022 at 15:32, Marcel Holtmann <marcel@holtmann.org> wrote:
>
> Hi Mike,
>
> > Fixes: 3e54c5890c87a ("Bluetooth: hci_event: Use of a function table to handle HCI events")
> > Signed-off-by: Mike Lothian <mike@fireburn.co.uk>
> > ---
> > net/bluetooth/hci_event.c | 8 --------
> > 1 file changed, 8 deletions(-)
> >
> > diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
> > index fc30f4c03d29..aa57fccd2e47 100644
> > --- a/net/bluetooth/hci_event.c
> > +++ b/net/bluetooth/hci_event.c
> > @@ -6818,14 +6818,6 @@ static void hci_event_func(struct hci_dev *hdev, u8 event, struct sk_buff *skb,
> >               return;
> >       }
> >
> > -     /* Just warn if the length is over max_len size it still be
> > -      * possible to partially parse the event so leave to callback to
> > -      * decide if that is acceptable.
> > -      */
> > -     if (skb->len > ev->max_len)
> > -             bt_dev_warn(hdev, "unexpected event 0x%2.2x length: %u > %u",
> > -                         event, skb->len, ev->max_len);
> > -
>
> which event type is this? You need to have a commit message giving details. I am also pretty sure that this is broken hardware and we can go for ratelimited version, but the warning is justified if the hardware is stupid. If our table is wrong, we fix the table, but not just silence an unpleasant warning.
>
> Regards
>
> Marcel
>

Hi Marcel

I noticed it had already been fixed in "Bluetooth: hci_event: Fix
HCI_EV_VENDOR max_len"

I've replied to that patch asking if it can be added to stable, would
be nice to get this into 5.17.0 before next week

Cheers

Mike