@@ -204,11 +204,6 @@ static int esp_select(ESPState *s)
s->ti_size = 0;
fifo8_reset(&s->fifo);
- if (s->current_req) {
- /* Started a new command before the old one finished. Cancel it. */
- scsi_req_cancel(s->current_req);
- }
-
s->current_dev = scsi_device_find(&s->bus, 0, target, 0);
if (!s->current_dev) {
/* No such drive */
@@ -235,6 +230,11 @@ static uint32_t get_cmd(ESPState *s, uint32_t maxlen)
uint32_t dmalen, n;
int target;
+ if (s->current_req) {
+ /* Started a new command before the old one finished. Cancel it. */
+ scsi_req_cancel(s->current_req);
+ }
+
target = s->wregs[ESP_WBUSID] & BUSID_DID;
if (s->dma) {
dmalen = MIN(esp_get_tc(s), maxlen);
There is currently a check in esp_select() to cancel any in-flight SCSI requests to ensure that issuing multiple select commands without continuing through the rest of the ESP state machine ignores all but the last SCSI request. This is also enforced through the addition of assert()s in esp_transfer_data() and scsi_read_data(). The get_cmd() function does not call esp_select() when TC == 0 which means it is possible for a fuzzer to trigger these assert()s by sending a select command when TC == 0 immediately after a valid SCSI CDB has been submitted. Since esp_select() is only called from get_cmd(), hoist the check to cancel in-flight SCSI requests from esp_select() into get_cmd() to ensure it is always called when executing a select command to initiate a new SCSI request. Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk> Closes: https://gitlab.com/qemu-project/qemu/-/issues/662 Closes: https://gitlab.com/qemu-project/qemu/-/issues/663 --- hw/scsi/esp.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)