6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Junrui Luo [ Upstream commit 27953c044974baf7e24dee3e9342fe0103dea80c ] The stateful decoder leaks uninitialized kernel heap memory to userspace. A process that can open the decoder video node gets it back in the CAPTURE buffers it dequeues. The reference frame and the compressed frame buffer are allocated with kvmalloc() in vicodec_start_streaming(), and the decoder can read them before they have been written. The first frame is allowed to be a P-frame, in which case it is decoded against a reference frame that was never produced, and the padding rows below the visible area are never written for any frame. Use kvzalloc() for both allocations. Fixes: 256bf813ba39 ("media: vicodec: add the virtual codec driver") Reported-by: Yuhao Jiang Assisted-by: Claude:claude-opus-5 Cc: stable@vger.kernel.org Signed-off-by: Junrui Luo Signed-off-by: Hans Verkuil Signed-off-by: Sasha Levin --- drivers/media/test-drivers/vicodec/vicodec-core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/media/test-drivers/vicodec/vicodec-core.c b/drivers/media/test-drivers/vicodec/vicodec-core.c index cdc3af33b4bbe..841dc03d0edd2 100644 --- a/drivers/media/test-drivers/vicodec/vicodec-core.c +++ b/drivers/media/test-drivers/vicodec/vicodec-core.c @@ -1606,9 +1606,9 @@ static int vicodec_start_streaming(struct vb2_queue *q, } state->ref_stride = q_data->coded_width * info->luma_alpha_step; - state->ref_frame.buf = kvmalloc(total_planes_size, GFP_KERNEL); + state->ref_frame.buf = kvzalloc(total_planes_size, GFP_KERNEL); state->ref_frame.luma = state->ref_frame.buf; - new_comp_frame = kvmalloc(ctx->comp_max_size, GFP_KERNEL); + new_comp_frame = kvzalloc(ctx->comp_max_size, GFP_KERNEL); if (!state->ref_frame.luma || !new_comp_frame) { kvfree(state->ref_frame.luma); -- 2.53.0