From: Mauro Carvalho Chehab Date: Wed, 11 Apr 2018 15:47:32 +0000 (-0400) Subject: media: v4l2-compat-ioctl32: prevent go past max size X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=ea72fbf588ac9c017224dcdaa2019ff52ca56fee;p=openwrt%2Fstaging%2Fblogic.git media: v4l2-compat-ioctl32: prevent go past max size As warned by smatch: drivers/media/v4l2-core/v4l2-compat-ioctl32.c:879 put_v4l2_ext_controls32() warn: check for integer overflow 'count' The access_ok() logic should check for too big arrays too. Cc: stable@vger.kernel.org Signed-off-by: Mauro Carvalho Chehab --- diff --git a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c index 4312935f1dfc..d03a44d89649 100644 --- a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c +++ b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c @@ -871,7 +871,7 @@ static int put_v4l2_ext_controls32(struct file *file, get_user(kcontrols, &kp->controls)) return -EFAULT; - if (!count) + if (!count || count > (U32_MAX/sizeof(*ucontrols))) return 0; if (get_user(p, &up->controls)) return -EFAULT;