Re: [PATCH v9 2/6] selftests/liveupdate: add test cases for LIVEUPDATE_IOCTL_CREATE_SESSION calls with invalid length

Mike Rapoport
2026-04-21T10:25:56Z

On Mon, Apr 20, 2026 at 03:15:10PM +0100, luca.boccassi@gmail.com wrote:
> From: Luca Boccassi <luca.boccassi@gmail.com>
>
> Verify that LIVEUPDATE_IOCTL_CREATE_SESSION ioctl which provide a name
> that is an empty string or too long are not allowed.
>
> Signed-off-by: Luca Boccassi <luca.boccassi@gmail.com>
> Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com>

Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>

> ---
> .../testing/selftests/liveupdate/liveupdate.c | 42 +++++++++++++++++++
> 1 file changed, 42 insertions(+)
>
> diff --git a/tools/testing/selftests/liveupdate/liveupdate.c b/tools/testing/selftests/liveupdate/liveupdate.c
> index c2878e3d5ef9..f0a8e600c154 100644
> --- a/tools/testing/selftests/liveupdate/liveupdate.c
> +++ b/tools/testing/selftests/liveupdate/liveupdate.c
> @@ -345,4 +345,46 @@ TEST_F(liveupdate_device, preserve_unsupported_fd)
> ASSERT_EQ(close(session_fd), 0);
> }
>
> +/*
> + * Test Case: Create Session with No Null Termination
> + *
> + * Verifies that filling the entire 64-byte name field with non-null characters
> + * (no '\0' terminator) is rejected by the kernel with EINVAL.
> + */
> +TEST_F(liveupdate_device, create_session_no_null_termination)
> +{
> + struct liveupdate_ioctl_create_session args = {};
> +
> + self->fd1 = open(LIVEUPDATE_DEV, O_RDWR);
> + if (self->fd1 < 0 && errno == ENOENT)
> + SKIP(return, "%s does not exist", LIVEUPDATE_DEV);
> + ASSERT_GE(self->fd1, 0);
> +
> + /* Fill entire name field with 'X', no null terminator */
> + args.size = sizeof(args);
> + memset(args.name, 'X', sizeof(args.name));
> +
> + EXPECT_LT(ioctl(self->fd1, LIVEUPDATE_IOCTL_CREATE_SESSION, &args), 0);
> + EXPECT_EQ(errno, EINVAL);
> +}
> +
> +/*
> + * Test Case: Create Session with Empty Name
> + *
> + * Verifies that creating a session with an empty string name fails
> + * with EINVAL.
> + */
> +TEST_F(liveupdate_device, create_session_empty_name)
> +{
> + int session_fd;
> +
> + self->fd1 = open(LIVEUPDATE_DEV, O_RDWR);
> + if (self->fd1 < 0 && errno == ENOENT)
> + SKIP(return, "%s does not exist", LIVEUPDATE_DEV);
> + ASSERT_GE(self->fd1, 0);
> +
> + session_fd = create_session(self->fd1, "");
> + EXPECT_EQ(session_fd, -EINVAL);
> +}
> +
> TEST_HARNESS_MAIN
> --
> 2.47.3
>

--
Sincerely yours,
Mike.