From c03fef652341b4ee8969b2a0229e2ef9046a9cee Mon Sep 17 00:00:00 2001
Message-Id: <c03fef652341b4ee8969b2a0229e2ef9046a9cee@dist-git>
From: Peter Krempa <pkrempa@redhat.com>
Date: Mon, 16 Mar 2020 22:11:35 +0100
Subject: [PATCH] qemuDomainGetGuestInfo: Don't try to free a negative number
 of entries
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'nfs' variable was set to -1 or -2 on agent failure. Cleanup then tried
to free 'nfs' elements of the array which resulted into a crash.

Make 'nfs' size_t and assign it only on successful agent call.

https://bugzilla.redhat.com/show_bug.cgi?id=1812965

Broken by commit 599ae372d8cf092

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
(cherry picked from commit 0fdb7385e416c9a0830dc60c0a56d55428963d74)

https://bugzilla.redhat.com/show_bug.cgi?id=1812965
Message-Id: <6eb97463bb380d32591ef82336095bf1ef370bca.1584391726.git.pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
---
 src/qemu/qemu_agent.c  |  2 +-
 src/qemu/qemu_driver.c | 12 ++++++++----
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/src/qemu/qemu_agent.c b/src/qemu/qemu_agent.c
index ef2d2c500b..f13126aeee 100644
--- a/src/qemu/qemu_agent.c
+++ b/src/qemu/qemu_agent.c
@@ -1954,7 +1954,7 @@ qemuAgentGetFSInfoFillDisks(virJSONValuePtr jsondisks,
     return 0;
 }
 
-/* Returns: 0 on success
+/* Returns: number of entries in '@info' on success
  *          -2 when agent command is not supported by the agent
  *          -1 otherwise
  */
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 8c7e90531a..0bdb2851ec 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -23101,7 +23101,7 @@ qemuDomainGetGuestInfo(virDomainPtr dom,
     g_autofree char *hostname = NULL;
     unsigned int supportedTypes = types;
     int rc;
-    int nfs = 0;
+    size_t nfs = 0;
     qemuAgentFSInfoPtr *agentfsinfo = NULL;
     size_t i;
 
@@ -23154,9 +23154,13 @@ qemuDomainGetGuestInfo(virDomainPtr dom,
         }
     }
     if (supportedTypes & VIR_DOMAIN_GUEST_INFO_FILESYSTEM) {
-        rc = nfs = qemuAgentGetFSInfo(agent, &agentfsinfo);
-        if (rc < 0 && !(rc == -2 && types == 0))
-            goto exitagent;
+        rc = qemuAgentGetFSInfo(agent, &agentfsinfo);
+        if (rc < 0) {
+            if (!(rc == -2 && types == 0))
+                goto exitagent;
+        } else {
+            nfs = rc;
+        }
     }
 
     ret = 0;
-- 
2.25.1