#

# Fixes a memory leak in libverto:vfree.

#

# Symbol vfree is defined as a macro vresize(X,0) and eventually realloc(X,0)

# gets called. According to realloc(3C), realloc with size=0 can return either

# NULL or a pointer that can be passed to free. This free-able pointer never

# gets freed in current code and leaks 8 B of memory on every event deletion.

#

# This patch replaces realloc(X,0) with free().

#

# Reported by security/krb5api testsuite and libumem.

#

# This patch has been contributed to MIT in

#    https://github.com/krb5/krb5/pull/294

#

# MIT requested this issue be reported to libverto project:

#    https://fedorahosted.org/libverto/ticket/13

# Patch source: in-house

#

--- a/src/util/verto/verto.c

+++ b/src/util/verto/verto.c

@@ -132,6 +132,11 @@ vresize(void *mem, size_t size)

 {

     if (!resize_cb)

         resize_cb = &realloc;

+    if (size == 0 && resize_cb == &realloc) {

+        /* avoid memleak as realloc(X,0) can return a free-able pointer */

+        free(mem);

+        return (NULL);

+    }

     return (*resize_cb)(mem, size);

 }