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From:   Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Date:   Fri, 1 May 2020 13:45:58 -0700
Message-ID: <CABBYNZ+5EykQDdsAagP27T1hazfg_+9qHhwt4M136dUZCwU1Kw@mail.gmail.com>
Subject: Re: [BlueZ PATCH v2] shared/gatt-client:Ignore orphaned characteristics
To:     Alain Michaud <alainm@chromium.org>
Cc:     "linux-bluetooth@vger.kernel.org" <linux-bluetooth@vger.kernel.org>
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Hi Alain,

On Fri, May 1, 2020 at 12:27 PM Alain Michaud <alainm@chromium.org> wrote:
>
> The gatt discovery proceedure simplification to discover all
> characteristics at once has exposed a device side issue where some
> device implementation reports orphaned characteristics.  While this
> technically shouldn't be allowed, some instances of this were observed
> (namely on some Android phones).
>
> The fix is to simply skip over orphaned characteristics and continue
> with everything else that is valid.
>
> This has been tested as part of the Android CTS tests against an
> affected platform and was confirmed to have worked around the issue.
>
> Signed-off-by: Alain Michaud <alainm@chromium.org>
> ---
>
>  src/shared/gatt-client.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/src/shared/gatt-client.c b/src/shared/gatt-client.c
> index 963ad619f..507b4d304 100644
> --- a/src/shared/gatt-client.c
> +++ b/src/shared/gatt-client.c
> @@ -632,7 +632,13 @@ static bool discover_descs(struct discovery_op *op, bool *discovering)
>                         util_debug(client->debug_callback, client->debug_data,
>                                 "Failed to insert characteristic at 0x%04x",
>                                 chrc_data->value_handle);
> -                       goto failed;
> +
> +                       /* Some devices have been seen reporting orphaned
> +                        * characteristics.  In order to favor interoperability
> +                        * we skip over characteristics in error
> +                        */
> +                       free(chrc_data);
> +                       continue;
>                 }
>
>                 if (gatt_db_attribute_get_handle(attr) !=
> --
> 2.26.2.526.g744177e7f7-goog
>

Applied, thanks. Note that I drop the Signed-off-by line since we
don't use that on userspace.

-- 
Luiz Augusto von Dentz