Hi Johan,
On Wed, Apr 25, 2012 at 2:35 PM, Johan Hedberg <johan.hedberg@xxxxxxxxx> wrote:
> Hi Vishal,
>
> On Wed, Apr 25, 2012, Vishal Agarwal wrote:
>> EIR data received from controller might contain padding zeros.
>> In this case data should be appended in the starting of padding
>> instead of at the end of padding. Data added after the padding will
>> be discarded by user space.
>>
>> Signed-off-by: Vishal Agarwal <vishal.agarwal@xxxxxxxxxxxxxx>
>> ---
>> include/net/bluetooth/hci_core.h | 21 +++++++++++++++++----
>> 1 files changed, 17 insertions(+), 4 deletions(-)
>>
>> diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
>> index ef6e654..9e42e2b 100644
>> --- a/include/net/bluetooth/hci_core.h
>> +++ b/include/net/bluetooth/hci_core.h
>> @@ -938,11 +938,24 @@ static inline bool eir_has_data_type(u8 *data, size_t data_len, u8 type)
>> static inline u16 eir_append_data(u8 *eir, u16 eir_len, u8 type, u8 *data,
>> u8 data_len)
>> {
>> - eir[eir_len++] = sizeof(type) + data_len;
>> - eir[eir_len++] = type;
>> - memcpy(&eir[eir_len], data, data_len);
>> - eir_len += data_len;
>> + u8 field_len;
>> + size_t parsed = 0;
>> +
>> + while (parsed < eir_len - 1) {
>> + field_len = eir[0];
>>
>> + if (field_len == 0) {
>> + eir[0] = sizeof(type) + data_len;
>> + eir[1] = type;
>> + memcpy(&eir[2], data, data_len);
>> + /* data_len + 1 byte for size + 1 byte for type */
>> + eir_len = parsed + data_len + 2;
>> + break;
>> + }
>> +
>> + parsed += field_len + 1;
>> + eir += field_len + 1;
>> + }
>> return eir_len;
>
> I don't really see the point of this. The eir_len parameter passed to
> this function is supposed to be the length of the significant
> (non-padded) data. I.e. it should already indicate the start of the
> padded zeroes. If you see misuse of this somewhere please submit a patch
> for that instead.
>
In function mgmt_device_found, which is called from
hci_extended_inquiry_result_evt eir_append_data function is called
without taking care of padding bytes. I will create a new function
which will return the padding offset in the EIR data andit will be
called in function mgmt_device_found before calling the
eir_append_data function.
> Johan
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Thanks
Vishal
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