On Mon, Jan 13, 2020 at 09:12:26PM +0200, Kamal Heib wrote:
> Make sure to return -EINVAL when the supplied string is bigger then
> IB_DEVICE_NODE_DESC_MAX.
>
> Fixes: c5bcbbb9fe00 ("IB: Allow userspace to set node description")
> Signed-off-by: Kamal Heib <kamalheib1@xxxxxxxxx>
> drivers/infiniband/core/sysfs.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/infiniband/core/sysfs.c b/drivers/infiniband/core/sysfs.c
> index 087682e6969e..55f4d7c1fcc9 100644
> +++ b/drivers/infiniband/core/sysfs.c
> @@ -1265,10 +1265,13 @@ static ssize_t node_desc_store(struct device *device,
> struct ib_device_modify desc = {};
> int ret;
>
> + if (count > IB_DEVICE_NODE_DESC_MAX)
> + return -EINVAL;
> +
> if (!dev->ops.modify_device)
> return -EOPNOTSUPP;
>
> - memcpy(desc.node_desc, buf, min_t(int, count, IB_DEVICE_NODE_DESC_MAX));
> + memcpy(desc.node_desc, buf, count);
I think this should just be written as
if (strscpy(desc.node_desc, buf, sizeof(desc.node_desc)) == -E2BIG)
return -EINVAL;
Jason
