From aef89c0b2417da79cb2062a95476288f9f203ab0 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Wed, 28 May 2025 23:22:14 +0300 Subject: [PATCH] media: gspca: Add bounds checking to firmware parser This sd_init() function reads the firmware. The firmware data holds a series of records and the function reads each record and sends the data to the device. The request_ihex_firmware() function calls ihex_validate_fw() which ensures that the total length of all the records won't read out of bounds of the fw->data[]. However, a potential issue is if there is a single very large record (larger than PAGE_SIZE) and that would result in memory corruption. Generally we trust the firmware, but it's always better to double check. Fixes: 49b61ec9b5af ("[media] gspca: Add new vicam subdriver") Cc: stable@vger.kernel.org Signed-off-by: Dan Carpenter Signed-off-by: Hans Verkuil --- drivers/media/usb/gspca/vicam.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/media/usb/gspca/vicam.c b/drivers/media/usb/gspca/vicam.c index d98343fd33fe3..91e177aa8136f 100644 --- a/drivers/media/usb/gspca/vicam.c +++ b/drivers/media/usb/gspca/vicam.c @@ -227,6 +227,7 @@ static int sd_init(struct gspca_dev *gspca_dev) const struct ihex_binrec *rec; const struct firmware *fw; u8 *firmware_buf; + int len; ret = request_ihex_firmware(&fw, VICAM_FIRMWARE, &gspca_dev->dev->dev); @@ -241,9 +242,14 @@ static int sd_init(struct gspca_dev *gspca_dev) goto exit; } for (rec = (void *)fw->data; rec; rec = ihex_next_binrec(rec)) { - memcpy(firmware_buf, rec->data, be16_to_cpu(rec->len)); + len = be16_to_cpu(rec->len); + if (len > PAGE_SIZE) { + ret = -EINVAL; + break; + } + memcpy(firmware_buf, rec->data, len); ret = vicam_control_msg(gspca_dev, 0xff, 0, 0, firmware_buf, - be16_to_cpu(rec->len)); + len); if (ret < 0) break; } -- 2.47.2