From 80c4bbb2b38513e9c3d84805fa61a0ee16d79c45 Mon Sep 17 00:00:00 2001 From: Michael Zaidman Date: Sat, 11 Apr 2026 09:24:37 +0300 Subject: [PATCH] HID: ft260: validate i2c input report length MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add two checks to ft260_raw_event() to prevent out-of-bounds reads from malicious or malfunctioning devices: First, reject reports shorter than the 2-byte header (report ID + length fields). Without this, even accessing xfer->length on a 1-byte report is an OOB read. Second, validate xfer->length against the actual data capacity of the received HID report. Each I2C data report ID (0xD0 through 0xDE) defines a different report size in the HID descriptor, so the available payload varies per report. A corrupted length field could cause memcpy to read beyond the report buffer. Reported-by: Sebastián Josué Alba Vives Signed-off-by: Michael Zaidman Signed-off-by: Jiri Kosina --- drivers/hid/hid-ft260.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/drivers/hid/hid-ft260.c b/drivers/hid/hid-ft260.c index 333341e80b0e..70e2eedb465a 100644 --- a/drivers/hid/hid-ft260.c +++ b/drivers/hid/hid-ft260.c @@ -1068,10 +1068,22 @@ static int ft260_raw_event(struct hid_device *hdev, struct hid_report *report, struct ft260_device *dev = hid_get_drvdata(hdev); struct ft260_i2c_input_report *xfer = (void *)data; + if (size < offsetof(struct ft260_i2c_input_report, data)) { + hid_err(hdev, "short report %d\n", size); + return -1; + } + if (xfer->report >= FT260_I2C_REPORT_MIN && xfer->report <= FT260_I2C_REPORT_MAX) { - ft260_dbg("i2c resp: rep %#02x len %d\n", xfer->report, - xfer->length); + ft260_dbg("i2c resp: rep %#02x len %d size %d\n", + xfer->report, xfer->length, size); + + if (xfer->length > size - + offsetof(struct ft260_i2c_input_report, data)) { + hid_err(hdev, "report %#02x: length %d exceeds HID report size\n", + xfer->report, xfer->length); + return -1; + } if ((dev->read_buf == NULL) || (xfer->length > dev->read_len - dev->read_idx)) {