File 0270-scsi-avoid-an-off-by-one-error-in-m.patch of Package qemu.10254

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File 0270-scsi-avoid-an-off-by-one-error-in-m.patch of Package qemu.10254

From bbc3912f33c6ba580a239821718c4310ef83b90d Mon Sep 17 00:00:00 2001
From: Prasad J Pandit <pjp@fedoraproject.org>
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 <bigbird475958471@gmail.com>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Message-Id: <20170424120634.12268-1-ppandit@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
(cherry picked from commit 24dfa9fa2f90a95ac33c7372de4f4f2c8a2c141f)
[BR: BSC#1037336 CVE-2017-8380]
Signed-off-by: Bruce Rogers <brogers@suse.com>
---
 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 9fbe76bf43..07601ae9ba 100644
--- a/hw/scsi/megasas.c
+++ b/hw/scsi/megasas.c
@@ -2141,15 +2141,15 @@ 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);

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File 0270-scsi-avoid-an-off-by-one-error-in-m.patch of Package qemu.10254

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