From 4e0870bfeceb26fef3b1b6b136529cb3be711cfe Mon Sep 17 00:00:00 2001
From: Richard Fuchs <rfuchs@sipwise.com>
Date: Thu, 28 Nov 2019 10:33:27 -0500
Subject: [PATCH] TT#71551 don't allocate zero-length memory blocks

medredis_fetch_records() allocates memory for 0 return records, which in
the calling code is understood as "no memory has been allocated",
leading to a slow leak. Returning early is correct as the mem block
pointer is set to NULL in this case.

Change-Id: I69a2d397edd15cb9e4033531a218658c7ca93b12
(cherry picked from commit 96e59f70f5bf6f58d9ff4ebf79981ac1d26e6299)
---
 medredis.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/medredis.c b/medredis.c
index 0c3a0b0..121bbdc 100644
--- a/medredis.c
+++ b/medredis.c
@@ -768,6 +768,9 @@ int medredis_fetch_records(med_callid_t *callid,
         (*count)++;
     }
 
+    if (!*count)
+        goto no_entries;
+
     *entries = (med_entry_t*)malloc(*count * sizeof(med_entry_t));
     if (!*entries) {
         L_ERROR("Failed to allocate memory for entries (cid '%s')\n", callid->value);
@@ -787,6 +790,7 @@ int medredis_fetch_records(med_callid_t *callid,
         L_DEBUG("Added entry with cid '%s' and method '%s'\n", d->callid, d->sip_method);
     }
 
+no_entries:
     g_list_free(records);
     g_list_free_full(keys, medredis_free_keys_list);