blob: af8d4ba8f465115d952646eb26eda66259f7ff54 [file] [log] [blame]
From f50ab86a2620bd7e8507af865b164655ee921661 Mon Sep 17 00:00:00 2001
From: Prasad J Pandit <pjp@fedoraproject.org>
Date: Thu, 14 May 2020 00:55:38 +0530
Subject: [PATCH] megasas: use unsigned type for reply_queue_head and check
index
A guest user may set 'reply_queue_head' field of MegasasState to
a negative value. Later in 'megasas_lookup_frame' it is used to
index into s->frames[] array. Use unsigned type to avoid OOB
access issue.
Also check that 'index' value stays within s->frames[] bounds
through the while() loop in 'megasas_lookup_frame' to avoid OOB
access.
Reported-by: Ren Ding <rding@gatech.edu>
Reported-by: Hanqing Zhao <hanqing@gatech.edu>
Reported-by: Alexander Bulekov <alxndr@bu.edu>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Acked-by: Alexander Bulekov <alxndr@bu.edu>
Message-Id: <20200513192540.1583887-2-ppandit@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Upstream-Status: Backport [f50ab86a2620bd7e8507af865b164655ee921661]
CVE: CVE-2020-13362
Signed-off-by: Sakib Sajal <sakib.sajal@windriver.com>
---
hw/scsi/megasas.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/hw/scsi/megasas.c b/hw/scsi/megasas.c
index af18c88b65..6ce598cd69 100644
--- a/hw/scsi/megasas.c
+++ b/hw/scsi/megasas.c
@@ -112,7 +112,7 @@ typedef struct MegasasState {
uint64_t reply_queue_pa;
void *reply_queue;
int reply_queue_len;
- int reply_queue_head;
+ uint16_t reply_queue_head;
int reply_queue_tail;
uint64_t consumer_pa;
uint64_t producer_pa;
@@ -445,7 +445,7 @@ static MegasasCmd *megasas_lookup_frame(MegasasState *s,
index = s->reply_queue_head;
- while (num < s->fw_cmds) {
+ while (num < s->fw_cmds && index < MEGASAS_MAX_FRAMES) {
if (s->frames[index].pa && s->frames[index].pa == frame) {
cmd = &s->frames[index];
break;
--
2.20.1