On Mon, Mar 20, 2017 at 10:11:42AM -0700, Eric Biggers wrote:

On Fri, Mar 10, 2017 at 10:58:23PM -0800, Eric Biggers wrote:

quoted

From: Eric Biggers <redacted>

The statx() system call currently accepts unknown flags when called with
a NULL path to operate on a file descriptor.  Left unchanged, this could
make it hard to introduce new query flags in the future, since
applications may not be able to tell whether a given flag is supported.

Fix this by failing the system call with EINVAL if any flags other than
KSTAT_QUERY_FLAGS are specified in combination with a NULL path.

Does anyone have comments on this patch?

Looks good to me.

I really think we need to get this in before v4.11 is released, since it deals
with the API.

Yes.  And we really need test for all of this.  Or just revert the
patches.  Shipping with untested syscalls is just a desaster.