Handle any error due to partial reads, timeouts etc. to avoid parsing uninitialized data subsequently. Also bail out if the parsing itself fails.
Cc: Dave Airlie airlied@redhat.com Cc: Lyude lyude@redhat.com Cc: Daniel Vetter daniel.vetter@ffwll.ch Signed-off-by: Imre Deak imre.deak@intel.com Reviewed-by: Lyude lyude@redhat.com --- drivers/gpu/drm/drm_dp_mst_topology.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index f7e292bf2baf..c6ae3e68918f 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -2200,11 +2200,17 @@ static void drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up) ret = drm_dp_dpcd_read(mgr->aux, basereg + curreply, replyblock, len); if (ret != len) { - DRM_DEBUG_KMS("failed to read a chunk\n"); + DRM_DEBUG_KMS("failed to read a chunk (len %d, ret %d)\n", + len, ret); + return; } + ret = drm_dp_sideband_msg_build(msg, replyblock, len, false); - if (ret == false) + if (!ret) { DRM_DEBUG_KMS("failed to build sideband msg\n"); + return; + } + curreply += len; replylen -= len; }