lkml.org 
[lkml]   [2022]   [Aug]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH AUTOSEL 5.15 44/69] drm/amd/display: Guard against ddc_pin being NULL for AUX
    Date
    From: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>

    [ Upstream commit bc19909f19fdc8253d720d11c948935786fbfa08 ]

    [Why]
    In the case where we don't support DMUB aux but we have DPIA links
    in the configuration we might try to message AUX using the legacy
    path - where DDC pin is NULL. This causes a NULL pointer dereference.

    [How]
    Guard against NULL DDC pin, return a failure for aux engine acquire.

    Reviewed-by: Michael Strauss <Michael.Strauss@amd.com>
    Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
    Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
    Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
    Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
    Signed-off-by: Sasha Levin <sashal@kernel.org>
    ---
    drivers/gpu/drm/amd/display/dc/dce/dce_aux.c | 5 +++++
    1 file changed, 5 insertions(+)

    diff --git a/drivers/gpu/drm/amd/display/dc/dce/dce_aux.c b/drivers/gpu/drm/amd/display/dc/dce/dce_aux.c
    index 3c3347341103..ae9c0df1a844 100644
    --- a/drivers/gpu/drm/amd/display/dc/dce/dce_aux.c
    +++ b/drivers/gpu/drm/amd/display/dc/dce/dce_aux.c
    @@ -563,6 +563,11 @@ int dce_aux_transfer_raw(struct ddc_service *ddc,
    memset(&aux_req, 0, sizeof(aux_req));
    memset(&aux_rep, 0, sizeof(aux_rep));

    + if (ddc_pin == NULL) {
    + *operation_result = AUX_RET_ERROR_ENGINE_ACQUIRE;
    + return -1;
    + }
    +
    aux_engine = ddc->ctx->dc->res_pool->engines[ddc_pin->pin_data->en];
    if (!acquire(aux_engine, ddc_pin)) {
    *operation_result = AUX_RET_ERROR_ENGINE_ACQUIRE;
    --
    2.35.1
    \
     
     \ /
      Last update: 2022-08-11 18:23    [W:5.547 / U:0.440 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site