[PATCH v2 10/16] esp.c: don't assert() if FIFO empty when executing esp_cdb_length()

[Mark Cave-Ayland]

This does not happen during normal usage, but can occur if the guest issues an
invalid ESP command sequence.

Reported-by: Chuhong Yuan <hsleste...@gmail.com>
Signed-off-by: Mark Cave-Ayland <mark.cave-ayl...@ilande.co.uk>
---
 hw/scsi/esp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/scsi/esp.c b/hw/scsi/esp.c
index 55143a1208..0050493e18 100644
--- a/hw/scsi/esp.c
+++ b/hw/scsi/esp.c
@@ -431,7 +431,7 @@ static int esp_cdb_length(ESPState *s)
     int cmdlen, len;
 
     cmdlen = fifo8_num_used(&s->cmdfifo);
-    if (cmdlen < s->cmdfifo_cdb_offset) {
+    if (cmdlen == 0 || cmdlen < s->cmdfifo_cdb_offset) {
         return 0;
     }
 
-- 
2.39.2