From: Prasad J Pandit <p...@fedoraproject.org> While writing a message in 'lsi_do_msgin', message length value in msg_len could be invalid, add check to avoid OOB access issue.
Reported-by: Ameya More <ameya.m...@oracle.com> Signed-off-by: Prasad J Pandit <p...@fedoraproject.org> --- hw/scsi/lsi53c895a.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/hw/scsi/lsi53c895a.c b/hw/scsi/lsi53c895a.c index d1e6534311..a266c5a113 100644 --- a/hw/scsi/lsi53c895a.c +++ b/hw/scsi/lsi53c895a.c @@ -205,7 +205,7 @@ typedef struct { /* Action to take at the end of a MSG IN phase. 0 = COMMAND, 1 = disconnect, 2 = DATA OUT, 3 = DATA IN. */ int msg_action; - int msg_len; + uint8_t msg_len; uint8_t msg[LSI_MAX_MSGIN_LEN]; /* 0 if SCRIPTS are running or stopped. * 1 if a Wait Reselect instruction has been issued. @@ -861,12 +861,15 @@ static void lsi_do_status(LSIState *s) static void lsi_do_msgin(LSIState *s) { - int len; + uint8_t len; trace_lsi_do_msgin(s->dbc, s->msg_len); s->sfbr = s->msg[0]; len = s->msg_len; if (len > s->dbc) len = s->dbc; + if (len > LSI_MAX_MSGIN_LEN) { + len = LSI_MAX_MSGIN_LEN; + } pci_dma_write(PCI_DEVICE(s), s->dnad, s->msg, len); /* Linux drivers rely on the last byte being in the SIDL. */ s->sidl = s->msg[len - 1]; @@ -2114,7 +2117,7 @@ static const VMStateDescription vmstate_lsi_scsi = { VMSTATE_INT32(carry, LSIState), VMSTATE_INT32(status, LSIState), VMSTATE_INT32(msg_action, LSIState), - VMSTATE_INT32(msg_len, LSIState), + VMSTATE_UINT8(msg_len, LSIState), VMSTATE_BUFFER(msg, LSIState), VMSTATE_INT32(waiting, LSIState), -- 2.17.2