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Date:   Mon, 1 Jul 2019 09:45:37 -0700
From:   Eric Biggers <ebiggers@kernel.org>
To:     David Howells <dhowells@redhat.com>
Cc:     linux-fsdevel@vger.kernel.org,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com
Subject: Re: [PATCH] vfs: move_mount: reject moving kernel internal mounts
Message-ID: <20190701164536.GA202431@gmail.com>
References: <CACT4Y+ZN8CZq7L1GQANr25extEqPASRERGVh+sD4-55cvWPOSg@mail.gmail.com>
 <20190629202744.12396-1-ebiggers@kernel.org>
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On Sat, Jun 29, 2019 at 01:27:44PM -0700, Eric Biggers wrote:
> 
> Reproducer:
> 
>     #include <unistd.h>
> 
>     #define __NR_move_mount         429
>     #define MOVE_MOUNT_F_EMPTY_PATH 0x00000004
> 
>     int main()
>     {
>     	  int fds[2];
> 
>     	  pipe(fds);
>         syscall(__NR_move_mount, fds[0], "", -1, "/", MOVE_MOUNT_F_EMPTY_PATH);
>     }

David, I'd like to add this as a regression test somewhere.

Can you point me to the tests for the new mount syscalls?

I checked LTP, kselftests, and xfstests, but nothing to be found.

- Eric