[Qemu-devel] [PATCH v2] virtio-rng: Add human-readable error message for negative max-bytes parameter

[John Snow <jsnow@redhat.com>]

If a negative integer is used for the max_bytes parameter, QEMU currently
calls abort() and leaves behind a core dump. This patch adds a simple
error message to make the reason for the termination clearer.

Signed-off-by: John Snow <jsnow@redhat.com>
---
v2: Changed 0L constant to (uint64_t)0 constant to match PRId64 format code
    on both 32bit and 64bit systems. Tested via -m32 flag.

 hw/virtio/virtio-rng.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/hw/virtio/virtio-rng.c b/hw/virtio/virtio-rng.c
index 1356aca..64c7d23 100644
--- a/hw/virtio/virtio-rng.c
+++ b/hw/virtio/virtio-rng.c
@@ -181,7 +181,11 @@ static void virtio_rng_device_realize(DeviceState *dev, Error **errp)
 
     vrng->vq = virtio_add_queue(vdev, 8, handle_input);
 
-    assert(vrng->conf.max_bytes <= INT64_MAX);
+    if (vrng->conf.max_bytes > INT64_MAX) {
+        error_set(errp, QERR_PROPERTY_VALUE_OUT_OF_RANGE, "virtio-rng",
+                  "max_bytes", vrng->conf.max_bytes, (uint64_t)0, INT64_MAX);
+        return;
+    }
     vrng->quota_remaining = vrng->conf.max_bytes;
 
     vrng->rate_limit_timer = timer_new_ms(QEMU_CLOCK_VIRTUAL,
-- 
1.9.3