The patch below does not apply to the 5.8-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 4462282a7253e3663790f8ab092a4107d905bd76 Mon Sep 17 00:00:00 2001
From: Josip Pavic Josip.Pavic@amd.com Date: Mon, 6 Jul 2020 15:43:39 -0400 Subject: [PATCH] drm/amd/display: handle failed allocation during stream construction
[Why] Failing to allocate a transfer function during stream construction leads to a null pointer dereference
[How] Handle the failed allocation by failing the stream construction
Cc: stable@vger.kernel.org Signed-off-by: Josip Pavic Josip.Pavic@amd.com Reviewed-by: Aric Cyr Aric.Cyr@amd.com Acked-by: Rodrigo Siqueira Rodrigo.Siqueira@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_stream.c b/drivers/gpu/drm/amd/display/dc/core/dc_stream.c index 3b897372ed27..d6989d115c5c 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_stream.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_stream.c @@ -56,7 +56,7 @@ void update_stream_signal(struct dc_stream_state *stream, struct dc_sink *sink) } }
-static void dc_stream_construct(struct dc_stream_state *stream, +static bool dc_stream_construct(struct dc_stream_state *stream, struct dc_sink *dc_sink_data) { uint32_t i = 0; @@ -118,11 +118,17 @@ static void dc_stream_construct(struct dc_stream_state *stream, update_stream_signal(stream, dc_sink_data);
stream->out_transfer_func = dc_create_transfer_func(); + if (stream->out_transfer_func == NULL) { + dc_sink_release(dc_sink_data); + return false; + } stream->out_transfer_func->type = TF_TYPE_BYPASS; stream->out_transfer_func->ctx = stream->ctx;
stream->stream_id = stream->ctx->dc_stream_id_count; stream->ctx->dc_stream_id_count++; + + return true; }
static void dc_stream_destruct(struct dc_stream_state *stream) @@ -164,13 +170,20 @@ struct dc_stream_state *dc_create_stream_for_sink(
stream = kzalloc(sizeof(struct dc_stream_state), GFP_KERNEL); if (stream == NULL) - return NULL; + goto alloc_fail;
- dc_stream_construct(stream, sink); + if (dc_stream_construct(stream, sink) == false) + goto construct_fail;
kref_init(&stream->refcount);
return stream; + +construct_fail: + kfree(stream); + +alloc_fail: + return NULL; }
struct dc_stream_state *dc_copy_stream(const struct dc_stream_state *stream)