On Thu, Dec 11, 2014 at 11:48 PM, Linux Kernel Mailing List <linux-kernel@vger.kernel.org> wrote: > Gitweb: > http://git.kernel.org/linus/;a=commit;h=b487b9ce9340a6e98d7f8277399304b23b7be456 > Commit: b487b9ce9340a6e98d7f8277399304b23b7be456 > Parent: bda157a40077447b25a1172a17b8ef81a2905cb7 > Refname: refs/heads/master > Author: Marcel Holtmann <mar...@holtmann.org> > AuthorDate: Fri Dec 5 10:55:57 2014 +0100 > Committer: Johan Hedberg <johan.hedb...@intel.com> > CommitDate: Fri Dec 5 12:37:35 2014 +0200 > > Bluetooth: Add framework for device found filtering based on UUID > > Using Start Service Discovery provides the option to specifiy a list > of UUID that are used to filter out device found events. This patch > provides the framework for hooking up the UUID filter. > > Signed-off-by: Marcel Holtmann <mar...@holtmann.org> > Signed-off-by: Johan Hedberg <johan.hedb...@intel.com> > --- > net/bluetooth/mgmt.c | 54 > ++++++++++++++++++++++++++++++++++++++++++++++++++-- > 1 file changed, 52 insertions(+), 2 deletions(-) > > diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c > index 1715c91..e39190a 100644 > --- a/net/bluetooth/mgmt.c > +++ b/net/bluetooth/mgmt.c > @@ -6802,6 +6802,11 @@ void mgmt_read_local_oob_data_complete(struct hci_dev > *hdev, u8 *hash192, > mgmt_pending_remove(cmd); > } > > +static bool eir_has_uuids(u8 *eir, u16 eir_len, u16 uuid_count, u8 > (*uuids)[16]) > +{ > + return false; > +} > + > void mgmt_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type, > u8 addr_type, u8 *dev_class, s8 rssi, u32 flags, > u8 *eir, u16 eir_len, u8 *scan_rsp, u8 scan_rsp_len) > @@ -6809,6 +6814,7 @@ void mgmt_device_found(struct hci_dev *hdev, bdaddr_t > *bdaddr, u8 link_type, > char buf[512]; > struct mgmt_ev_device_found *ev = (void *) buf; > size_t ev_size; > + bool match;
net/bluetooth/mgmt.c: In function ‘mgmt_device_found’: net/bluetooth/mgmt.c:6993: warning: ‘match’ may be used uninitialized in this function All tests for "match" are protected by "if (hdev->discovery.uuid_count > 0)", so we only have to care about that case. > /* Don't send events for a non-kernel initiated discovery. With > * LE one exception is if we have pend_le_reports > 0 in which > @@ -6843,15 +6849,59 @@ void mgmt_device_found(struct hci_dev *hdev, bdaddr_t > *bdaddr, u8 link_type, > ev->rssi = rssi; > ev->flags = cpu_to_le32(flags); > > - if (eir_len > 0) > + if (eir_len > 0) { > + /* When using service discovery and a list of UUID is > + * provided, results with no matching UUID should be > + * dropped. In case there is a match the result is > + * kept and checking possible scan response data > + * will be skipped. > + */ > + if (hdev->discovery.uuid_count > 0) { > + match = eir_has_uuids(eir, eir_len, > + hdev->discovery.uuid_count, > + hdev->discovery.uuids); > + if (!match) > + return; > + } If we get here and if (hdev->discovery.uuid_count > 0), "match" must be true. > + > + /* Copy EIR or advertising data into event */ > memcpy(ev->eir, eir, eir_len); > + } else { > + /* When using service discovery and a list of UUID is > + * provided, results with empty EIR or advertising data > + * should be dropped since they do not match any UUID. > + */ > + if (hdev->discovery.uuid_count > 0) > + return; We will never get here if (hdev->discovery.uuid_count > 0). > + } Hence if we get here and if (hdev->discovery.uuid_count > 0), "match" is always true. > if (dev_class && !eir_has_data_type(ev->eir, eir_len, > EIR_CLASS_OF_DEV)) > eir_len = eir_append_data(ev->eir, eir_len, EIR_CLASS_OF_DEV, > dev_class, 3); > > - if (scan_rsp_len > 0) > + if (scan_rsp_len > 0) { > + /* When using service discovery and a list of UUID is > + * provided, results with no matching UUID should be > + * dropped if there is no previous match from the > + * advertising data. > + */ > + if (hdev->discovery.uuid_count > 0) { > + if (!match && !eir_has_uuids(scan_rsp, scan_rsp_len, "match" is true, so this whole block is useless. > + > hdev->discovery.uuid_count, > + hdev->discovery.uuids)) > + return; > + } > + > + /* Append scan response data to event */ > memcpy(ev->eir + eir_len, scan_rsp, scan_rsp_len); > + } else { > + /* When using service discovery and a list of UUID is > + * provided, results with empty scan response and no > + * previous matched advertising data should be dropped. > + */ > + if (hdev->discovery.uuid_count > 0 && !match) "match" is true, so this whole block is useless. > + return; > + } > > ev->eir_len = cpu_to_le16(eir_len + scan_rsp_len); > ev_size = sizeof(*ev) + eir_len + scan_rsp_len; Is my analysis correct? Am I missing something? Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/