From 1e84a807c98a71f767fd1f609637bc5944f916cb Mon Sep 17 00:00:00 2001 From: Even Xu Date: Fri, 26 Dec 2025 11:39:53 +0800 Subject: [PATCH] HID: Intel-thc-hid: Intel-thc: Add safety check for reading DMA buffer [ Upstream commit a9a917998d172ec117f9e9de1919174153c0ace4 ] Add DMA buffer readiness check before reading DMA buffer to avoid unexpected NULL pointer accessing. Signed-off-by: Even Xu Tested-by: Rui Zhang Signed-off-by: Benjamin Tissoires Signed-off-by: Sasha Levin --- drivers/hid/intel-thc-hid/intel-thc/intel-thc-dma.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/hid/intel-thc-hid/intel-thc/intel-thc-dma.c b/drivers/hid/intel-thc-hid/intel-thc/intel-thc-dma.c index a0c368aa7979..6ee675e0a738 100644 --- a/drivers/hid/intel-thc-hid/intel-thc/intel-thc-dma.c +++ b/drivers/hid/intel-thc-hid/intel-thc/intel-thc-dma.c @@ -575,6 +575,11 @@ static int read_dma_buffer(struct thc_device *dev, return -EINVAL; } + if (!read_config->prd_tbls || !read_config->sgls[prd_table_index]) { + dev_err_once(dev->dev, "PRD tables are not ready yet\n"); + return -EINVAL; + } + prd_tbl = &read_config->prd_tbls[prd_table_index]; mes_len = calc_message_len(prd_tbl, &nent); if (mes_len > read_config->max_packet_size) {