The virtio-rng test to verify effective handling of oversized return buffers checks that an (undocumented) error is raised, instead of the real concern, which is the surrounding buffer integrity following a rng function call. Update the test to check that the other contents of a buffer remain unchanged instead of looking for an error code.
Signed-off-by: Kavin Gunasekara <[email protected]> --- test/dm/virtio_rng.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/test/dm/virtio_rng.c b/test/dm/virtio_rng.c index e404b08484e..7c3dd50ef3e 100644 --- a/test/dm/virtio_rng.c +++ b/test/dm/virtio_rng.c @@ -19,12 +19,19 @@ struct virtio_rng_priv { struct virtqueue *rng_vq; }; +#define BUFFER_SIZE 16 +#define CANARY "CANARYCANARYCANARYCANARY" + /* Test the virtio-rng driver validates the used size */ static int dm_test_virtio_rng_check_len(struct unit_test_state *uts) { struct udevice *bus, *dev; struct virtio_rng_priv *priv; - u8 buffer[16]; + u8 buffer[BUFFER_SIZE + sizeof(CANARY)]; + + /* write known data to buffer */ + memset(buffer, 0xaa, sizeof(buffer)); + memcpy(buffer + BUFFER_SIZE, CANARY, sizeof(CANARY)); /* check probe success */ ut_assertok(uclass_first_device_err(UCLASS_VIRTIO, &bus)); @@ -44,7 +51,10 @@ static int dm_test_virtio_rng_check_len(struct unit_test_state *uts) priv->rng_vq->vring.used->ring[0].len = U32_MAX; /* check the driver gracefully handles the error */ - ut_asserteq(-EIO, dm_rng_read(dev, buffer, sizeof(buffer))); + dm_rng_read(dev, buffer, BUFFER_SIZE); + + /* check for the canary bytes behind the real buffer */ + ut_asserteq_mem(buffer + BUFFER_SIZE, CANARY, sizeof(CANARY)); return 0; } -- 2.34.1
