From: Prasad J Pandit Date: Mon, 24 Apr 2017 17:36:34 +0530 Subject: [PATCH] scsi: avoid an off-by-one error in megasas_mmio_write While reading magic sequence(MFI_SEQ) in megasas_mmio_write, an off-by-one error could occur as 's->adp_reset' index is not reset after reading the last sequence. Reported-by: YY Z Signed-off-by: Prasad J Pandit Message-Id: <20170424120634.12268-1-ppandit@redhat.com> Signed-off-by: Paolo Bonzini (cherry picked from commit 24dfa9fa2f90a95ac33c7372de4f4f2c8a2c141f) --- hw/scsi/megasas.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/hw/scsi/megasas.c b/hw/scsi/megasas.c index 84b8caf901..804122ab05 100644 --- a/hw/scsi/megasas.c +++ b/hw/scsi/megasas.c @@ -2138,15 +2138,15 @@ static void megasas_mmio_write(void *opaque, hwaddr addr, case MFI_SEQ: trace_megasas_mmio_writel("MFI_SEQ", val); /* Magic sequence to start ADP reset */ - if (adp_reset_seq[s->adp_reset] == val) { - s->adp_reset++; + if (adp_reset_seq[s->adp_reset++] == val) { + if (s->adp_reset == 6) { + s->adp_reset = 0; + s->diag = MFI_DIAG_WRITE_ENABLE; + } } else { s->adp_reset = 0; s->diag = 0; } - if (s->adp_reset == 6) { - s->diag = MFI_DIAG_WRITE_ENABLE; - } break; case MFI_DIAG: trace_megasas_mmio_writel("MFI_DIAG", val);