A large cs->count from userspace may overflow the allocation size, leading to memory corruption. v4l2_g_ext_ctrls() can be reached from subdev_do_ioctl() or __video_do_ioctl().
Use kmalloc_array() to avoid the overflow. Signed-off-by: Xi Wang <[email protected]> --- drivers/media/video/v4l2-ctrls.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/drivers/media/video/v4l2-ctrls.c b/drivers/media/video/v4l2-ctrls.c index 18015c0..f355fd5 100644 --- a/drivers/media/video/v4l2-ctrls.c +++ b/drivers/media/video/v4l2-ctrls.c @@ -1996,7 +1996,8 @@ int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct v4l2_ext_controls *cs return class_check(hdl, cs->ctrl_class); if (cs->count > ARRAY_SIZE(helper)) { - helpers = kmalloc(sizeof(helper[0]) * cs->count, GFP_KERNEL); + helpers = kmalloc_array(cs->count, sizeof(helper[0]), + GFP_KERNEL); if (helpers == NULL) return -ENOMEM; } -- 1.7.5.4 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
