From a59cf84441f9a17323c89452cec2bf16724c48a9 Mon Sep 17 00:00:00 2001 From: HyeongJun An Date: Fri, 17 Jul 2026 18:16:22 +0900 Subject: [PATCH] HID: intel-thc-hid: intel-quickspi: validate report size before copy write_cmd_to_txdma() builds an output report in qsdev->report_buf, a heap buffer allocated in quickspi_alloc_report_buf() to the device-descriptor derived max_report_len (a few hundred bytes for a touch controller). It copies the caller-supplied report into that buffer: memcpy(write_buf->content, report_buf, report_buf_len); The HID core caps a report at HID_MAX_BUFFER_SIZE (16384) by default, and quickspi_hid_ll_driver does not set max_buffer_size, so the length reaches the driver unbounded. A hidraw SET_REPORT/SET_FEATURE ioctl carrying a report larger than max_report_len therefore overflows report_buf with attacker-controlled length and content. Record the report_buf allocation size and reject reports that do not fit before copying, matching the equivalent guard in the intel-quicki2c sibling (quicki2c_init_write_buf()) and the hid-goodix-spi fix. write_cmd_to_txdma() writes the output report header ahead of the content in the same buffer, so size the allocation to cover the header as well. That keeps the added bound from rejecting a maximum-sized report. Fixes: 9d8d51735a3a ("HID: intel-thc-hid: intel-quickspi: Add HIDSPI protocol implementation") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-8 Signed-off-by: HyeongJun An Reviewed-by: Even Xu Signed-off-by: Jiri Kosina --- drivers/hid/intel-thc-hid/intel-quickspi/pci-quickspi.c | 9 ++++++++- drivers/hid/intel-thc-hid/intel-quickspi/quickspi-dev.h | 1 + .../hid/intel-thc-hid/intel-quickspi/quickspi-protocol.c | 3 +++ 3 files changed, 12 insertions(+), 1 deletion(-) diff --git a/drivers/hid/intel-thc-hid/intel-quickspi/pci-quickspi.c b/drivers/hid/intel-thc-hid/intel-quickspi/pci-quickspi.c index 4ae2e1718b30..da5ecfcd0fbf 100644 --- a/drivers/hid/intel-thc-hid/intel-quickspi/pci-quickspi.c +++ b/drivers/hid/intel-thc-hid/intel-quickspi/pci-quickspi.c @@ -555,7 +555,14 @@ static int quickspi_alloc_report_buf(struct quickspi_device *qsdev) max_report_len = max(le16_to_cpu(qsdev->dev_desc.max_output_len), le16_to_cpu(qsdev->dev_desc.max_input_len)); - qsdev->report_buf = devm_kzalloc(qsdev->dev, max_report_len, GFP_KERNEL); + /* + * write_cmd_to_txdma() writes the output report header ahead of the + * content in this buffer, so it has to hold both. + */ + qsdev->report_buf_size = HIDSPI_OUTPUT_REPORT_SIZE(max_report_len); + + qsdev->report_buf = devm_kzalloc(qsdev->dev, qsdev->report_buf_size, + GFP_KERNEL); if (!qsdev->report_buf) return -ENOMEM; diff --git a/drivers/hid/intel-thc-hid/intel-quickspi/quickspi-dev.h b/drivers/hid/intel-thc-hid/intel-quickspi/quickspi-dev.h index bf5e18f5a5f4..0ed964bfe3dd 100644 --- a/drivers/hid/intel-thc-hid/intel-quickspi/quickspi-dev.h +++ b/drivers/hid/intel-thc-hid/intel-quickspi/quickspi-dev.h @@ -157,6 +157,7 @@ struct quickspi_device { u8 *report_descriptor; u8 *input_buf; u8 *report_buf; + u32 report_buf_size; u32 report_len; wait_queue_head_t reset_ack_wq; diff --git a/drivers/hid/intel-thc-hid/intel-quickspi/quickspi-protocol.c b/drivers/hid/intel-thc-hid/intel-quickspi/quickspi-protocol.c index cb19057f1191..db6054843e77 100644 --- a/drivers/hid/intel-thc-hid/intel-quickspi/quickspi-protocol.c +++ b/drivers/hid/intel-thc-hid/intel-quickspi/quickspi-protocol.c @@ -30,6 +30,9 @@ static int write_cmd_to_txdma(struct quickspi_device *qsdev, write_buf = (struct output_report *)qsdev->report_buf; + if (HIDSPI_OUTPUT_REPORT_SIZE(report_buf_len) > qsdev->report_buf_size) + return -EINVAL; + write_buf->output_hdr.report_type = report_type; write_buf->output_hdr.content_len = cpu_to_le16(report_buf_len); write_buf->output_hdr.content_id = report_id;