From bf72013b84bcc8e0f26f65f8354f7d7861d044b3 Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Tue, 8 Aug 2017 08:56:21 -0400 Subject: media: uvcvideo: Prevent heap overflow when accessing mapped controls commit 7e09f7d5c790278ab98e5f2c22307ebe8ad6e8ba upstream. The size of uvc_control_mapping is user controlled leading to a potential heap overflow in the uvc driver. This adds a check to verify the user provided size fits within the bounds of the defined buffer size. Originally-from: Richard Simmons Change-Id: Iecff8a3172e2096379d647ba4373cbd0b35d7479 Signed-off-by: Guenter Roeck Reviewed-by: Laurent Pinchart Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman --- drivers/media/usb/uvc/uvc_ctrl.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'drivers') diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c index f61d1d7ba..5f2a67242 100644 --- a/drivers/media/usb/uvc/uvc_ctrl.c +++ b/drivers/media/usb/uvc/uvc_ctrl.c @@ -1952,6 +1952,13 @@ int uvc_ctrl_add_mapping(struct uvc_video_chain *chain, goto done; } + /* Validate the user-provided bit-size and offset */ + if (mapping->size > 32 || + mapping->offset + mapping->size > ctrl->info.size * 8) { + ret = -EINVAL; + goto done; + } + list_for_each_entry(map, &ctrl->info.mappings, list) { if (mapping->id == map->id) { uvc_trace(UVC_TRACE_CONTROL, "Can't add mapping '%s', " -- cgit v1.2.3