[Intel-gfx] [PATCH v3] drm/i915/tc: Fix -Wformat-truncation in intel_tc_port_init

[Jani Nikula]

On Fri, 27 Oct 2023, "Kahola, Mika" <mika.kahola at intel.com> wrote:
>> -----Original Message-----
>> From: Das, Nirmoy <nirmoy.das at intel.com>
>> Sent: Thursday, October 26, 2023 3:57 PM
>> To: intel-gfx at lists.freedesktop.org
>> Cc: Das, Nirmoy <nirmoy.das at intel.com>; Kahola, Mika <mika.kahola at intel.com>; Deak, Imre <imre.deak at intel.com>; Nikula,
>> Jani <jani.nikula at intel.com>; Hajda, Andrzej <andrzej.hajda at intel.com>
>> Subject: [PATCH v3] drm/i915/tc: Fix -Wformat-truncation in intel_tc_port_init
>>
>> Fix below compiler warning:
>>
>> intel_tc.c:1879:11: error: ‘%d’ directive output may be truncated writing between 1 and 11 bytes into a region of size 3 [-
>> Werror=format-truncation=] "%c/TC#%d", port_name(port), tc_port + 1);
>>            ^~
>> intel_tc.c:1878:2: note: ‘snprintf’ output between 7 and 17 bytes into a destination of size 8
>>   snprintf(tc->port_name, sizeof(tc->port_name),
>>   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>     "%c/TC#%d", port_name(port), tc_port + 1);
>>     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>
>> v2: use kasprintf(Imre)
>> v3: use const for port_name, and fix tc mem leak(Imre)
>>
>> Fixes: 3eafcddf766b ("drm/i915/tc: Move TC port fields to a new intel_tc_port struct")
>> Cc: Mika Kahola <mika.kahola at intel.com>
>> Cc: Imre Deak <imre.deak at intel.com>
>> Cc: Jani Nikula <jani.nikula at intel.com>
>> Signed-off-by: Nirmoy Das <nirmoy.das at intel.com>
>> Reviewed-by: Andrzej Hajda <andrzej.hajda at intel.com>
>> Reviewed-by: Imre Deak <imre.deak at intel.com>
>
> Reviewed-by: Mika Kahola <mika.kahola at intel.com>

Thanks for the patch and reviews, pushed to din.

BR,
Jani.

>
>> ---
>>  drivers/gpu/drm/i915/display/intel_tc.c | 11 ++++++++---
>>  1 file changed, 8 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/display/intel_tc.c b/drivers/gpu/drm/i915/display/intel_tc.c
>> index 37b0f8529b4f..f64d348a969e 100644
>> --- a/drivers/gpu/drm/i915/display/intel_tc.c
>> +++ b/drivers/gpu/drm/i915/display/intel_tc.c
>> @@ -58,7 +58,7 @@ struct intel_tc_port {
>>       struct delayed_work link_reset_work;
>>       int link_refcount;
>>       bool legacy_port:1;
>> -     char port_name[8];
>> +     const char *port_name;
>>       enum tc_port_mode mode;
>>       enum tc_port_mode init_mode;
>>       enum phy_fia phy_fia;
>> @@ -1875,8 +1875,12 @@ int intel_tc_port_init(struct intel_digital_port *dig_port, bool is_legacy)
>>       else
>>               tc->phy_ops = &icl_tc_phy_ops;
>>
>> -     snprintf(tc->port_name, sizeof(tc->port_name),
>> -              "%c/TC#%d", port_name(port), tc_port + 1);
>> +     tc->port_name = kasprintf(GFP_KERNEL, "%c/TC#%d", port_name(port),
>> +                               tc_port + 1);
>> +     if (!tc->port_name) {
>> +             kfree(tc);
>> +             return -ENOMEM;
>> +     }
>>
>>       mutex_init(&tc->lock);
>>       /* TODO: Combine the two works */
>> @@ -1897,6 +1901,7 @@ void intel_tc_port_cleanup(struct intel_digital_port *dig_port)  {
>>       intel_tc_port_suspend(dig_port);
>>
>> +     kfree(dig_port->tc->port_name);
>>       kfree(dig_port->tc);
>>       dig_port->tc = NULL;
>>  }
>> --
>> 2.42.0
>

-- 
Jani Nikula, Intel