When about to execute a SCSI command, ensure that cmdfifo is not empty and current_dev is non-NULL. This can happen if the guest tries to execute a TI (Transfer Information) command without issuing one of the select commands first.
Buglink: https://bugs.launchpad.net/qemu/+bug/1910723 Buglink: https://bugs.launchpad.net/qemu/+bug/1909247 Signed-off-by: Mark Cave-Ayland <mark.cave-ayl...@ilande.co.uk> Reviewed-by: Philippe Mathieu-Daudé <f4...@amsat.org> Tested-by: Alexander Bulekov <alx...@bu.edu> --- hw/scsi/esp.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/hw/scsi/esp.c b/hw/scsi/esp.c index 1aa2caf57d..4decbbfc29 100644 --- a/hw/scsi/esp.c +++ b/hw/scsi/esp.c @@ -284,6 +284,9 @@ static void do_busid_cmd(ESPState *s, uint8_t busid) trace_esp_do_busid_cmd(busid); lun = busid & 7; cmdlen = fifo8_num_used(&s->cmdfifo); + if (!cmdlen || !s->current_dev) { + return; + } esp_fifo_pop_buf(&s->cmdfifo, buf, cmdlen); current_lun = scsi_device_find(&s->bus, 0, s->current_dev->id, lun); -- 2.20.1
