Return-Path: Date: Fri, 21 Dec 2012 21:31:12 +0200 From: Johan Hedberg To: Syam Sidhardhan Cc: linux-bluetooth@vger.kernel.org Subject: Re: [PATCH 1/2] Bluetooth: Fix to update EIR for uuid16 properly Message-ID: <20121221193112.GA31432@x220.ger.corp.intel.com> References: <1356097469-24073-1-git-send-email-s.syam@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1356097469-24073-1-git-send-email-s.syam@samsung.com> Sender: linux-bluetooth-owner@vger.kernel.org List-ID: Hi Syam, On Fri, Dec 21, 2012, Syam Sidhardhan wrote: > If we register a uuid other than uuid16, especially custom 128 bit uuid > then nothing is updated in the EIR and it was broken. > > After registering a 16 bit uuid. ex: "sdptool add SP", we can see the > uuid in the EIR as below. > < 0000: 01 52 0c f1 00 08 09 52 65 64 77 6f 6f 64 15 03 .R.....Redwood.. > 0010: 01 11 32 11 2f 11 06 11 05 11 0a 11 0e 11 0c 11 ..2./........... > 0020: 1f 11 12 11 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0040: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0050: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0090: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 00a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 00b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 00c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 00d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 00e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 00f0: 00 00 00 00 00 ..... > > 0000: 04 0e 04 01 52 0c 00 ....R.. > > But after register a user defined 128 bit uuid, nothing is > updated in the EIR. > > < 0000: 01 52 0c f1 00 08 09 52 65 64 77 6f 6f 64 00 00 .R.....Redwood.. > 0010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0040: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0050: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 0090: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 00a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 00b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 00c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 00d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 00e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 00f0: 00 00 00 00 00 ..... > > 0000: 04 0e 04 01 52 0c 00 ....R.. > > With this fix, we can see the EIR is updated properly. > > Signed-off-by: Syam Sidhardhan > --- > net/bluetooth/mgmt.c | 2 -- > 1 file changed, 2 deletions(-) > > diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c > index f559b96..512a3f5 100644 > --- a/net/bluetooth/mgmt.c > +++ b/net/bluetooth/mgmt.c > @@ -514,8 +514,6 @@ static void create_eir(struct hci_dev *hdev, u8 *data) > u16 uuid16; > > uuid16 = get_uuid16(uuid->uuid); > - if (uuid16 == 0) > - return; > > if (uuid16 < 0x1100) > continue; Nak. The bug is real and should be fixed but your fix is wrong. The right fix it to convert this return statement into a continue statement since we do still want to check for a 0 return value from get_uuid16. Along with this patch please prepare another one to increment the mgmt revision. These two should go together to upstream trees so that we can introduce a check in user space to know whether it's safe to pass non-16bit UUIDs to the kernel or not. Johan