Re: [PATCH] Bluetooth: hci_conn_failed: Fixes memory leak

[Luiz Augusto von Dentz]

Hi Yuran,

On Sat, Oct 7, 2023 at 10:39 AM Yuran Pereira <yuran.pereira@xxxxxxxxxxx> wrote:
>
> Hello Greg,
> My apologies, I just noticed that my patch is based on the mainline tree. I'll re-submit one based on the Bluetooth tree and I'll ensure to include the commit id that it's fixing.
>
> Thanks,
> Yuran Pereira
> ________________________________
> De: Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx>
> Enviado: 7 de outubro de 2023 11:41
> Para: Yuran Pereira <yuran.pereira@xxxxxxxxxxx>
> Cc: marcel@xxxxxxxxxxxx <marcel@xxxxxxxxxxxx>; johan.hedberg@xxxxxxxxx <johan.hedberg@xxxxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx <linux-kernel@xxxxxxxxxxxxxxx>; linux-bluetooth@xxxxxxxxxxxxxxx <linux-bluetooth@xxxxxxxxxxxxxxx>; luiz.dentz@xxxxxxxxx <luiz.dentz@xxxxxxxxx>; syzbot+39ec16ff6cc18b1d066d@xxxxxxxxxxxxxxxxxxxxxxxxx <syzbot+39ec16ff6cc18b1d066d@xxxxxxxxxxxxxxxxxxxxxxxxx>; linux-kernel-mentees@xxxxxxxxxxxxxxxxxxxxxxxxx <linux-kernel-mentees@xxxxxxxxxxxxxxxxxxxxxxxxx>
> Assunto: Re: [PATCH] Bluetooth: hci_conn_failed: Fixes memory leak
>
> On Sat, Oct 07, 2023 at 05:09:01PM +0530, Yuran Pereira wrote:
> > The hci_conn_failed() function currently calls hci_connect_cfm(), which
> > indirectly leads to the allocation of an l2cap_conn struct in l2cap_conn_add().
> > This operation results in a memory leak, as the l2cap_conn structure
> > becomes unreferenced.
> >
> > To address this issue and prevent the memory leak, this patch modifies
> > hci_conn_failed() to replace the call to hci_connect_cfm() with a
> > call to hci_disconn_cfm().

I suspect this is not quite right, hci_disconn_cfm is called when a
disconnection has been requested, hci_connect_cfm is correct here
since it is meant to notify the result of connection request procedure
so I can only assume that the culprit here is that hci_conn_failed is
called with status 0 which is invalid and needs fixing.

> > Reported-by: syzbot+39ec16ff6cc18b1d066d@xxxxxxxxxxxxxxxxxxxxxxxxx
> > Signed-off-by: Yuran Pereira <yuran.pereira@xxxxxxxxxxx>
> > ---
> >  net/bluetooth/hci_conn.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
>
> What commit id does this fix?
>
> thanks,
>
> greg k-h



-- 
Luiz Augusto von Dentz