From 2b588db82d2c210e84da129a223bb403d3131abe Mon Sep 17 00:00:00 2001 From: Alexander Strakh Date: Tue, 17 Nov 2009 19:43:38 -0300 Subject: [PATCH] V4L/DVB (13379): quickcam_messenger: possible buffer overflow while use strncat In driver ./drivers/media/video/usbvideo/quickcam_messenger.c in line 91: 91 usb_make_path(dev, cam->input_physname, sizeof(cam->input_physname)); After this line we use strncat: 92 strncat(cam->input_physname, "/input0", sizeof(cam->input_physname)); where sizeof(cam->input_physname) returns length of cam->input_phisname without length for null-symbol. But this parameter must be - "maximum numbers of bytes to copy", i.e.: sizeof(cam->input_physname)-strlen(cam->input_physname)-1. In this case, after call to usb_make_path the similar drivers use strlcat. Like in: drivers/hid/usbhid/hid-core.c: 1152 usb_make_path(dev, hid->phys, sizeof(hid->phys)); 1153 strlcat(hid->phys, "/input", sizeof(hid->phys)); Found by Linux Driver Verification Project. Use strlcat instead of strncat. Signed-off-by: Alexander Strakh Signed-off-by: Andrew Morton Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/usbvideo/quickcam_messenger.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/media/video/usbvideo/quickcam_messenger.c b/drivers/media/video/usbvideo/quickcam_messenger.c index 803d3e4..c4d1b96 100644 --- a/drivers/media/video/usbvideo/quickcam_messenger.c +++ b/drivers/media/video/usbvideo/quickcam_messenger.c @@ -89,7 +89,7 @@ static void qcm_register_input(struct qcm *cam, struct usb_device *dev) int error; usb_make_path(dev, cam->input_physname, sizeof(cam->input_physname)); - strncat(cam->input_physname, "/input0", sizeof(cam->input_physname)); + strlcat(cam->input_physname, "/input0", sizeof(cam->input_physname)); cam->input = input_dev = input_allocate_device(); if (!input_dev) { -- 2.7.4