[Qemu-devel] [PATCHv2 2/2] envlist.c: handle strdup failure

[Jim Meyering <jim@meyering.net>]

From: Jim Meyering <meyering@redhat.com>

Without this, envlist_to_environ may silently fail to copy all
strings into the destination buffer, and both callers would leak
any env strings allocated after a failing strdup, because the
freeing code stops at the first NULL pointer.

Signed-off-by: Jim Meyering <meyering@redhat.com>
---
 envlist.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/envlist.c b/envlist.c
index be0addb..7532091 100644
--- a/envlist.c
+++ b/envlist.c
@@ -234,8 +234,16 @@ envlist_to_environ(const envlist_t *envlist, size_t *count)
                 return (NULL);

         for (entry = envlist->el_entries.lh_first; entry != NULL;
-            entry = entry->ev_link.le_next) {
-                *(penv++) = strdup(entry->ev_var);
+             entry = entry->ev_link.le_next, penv++) {
+                *penv = strdup(entry->ev_var);
+                if (*penv == NULL) {
+                        char **e = env;
+                        while (e <= penv) {
+                                free(*e++);
+                        }
+                        free(env);
+                        return NULL;
+                }
         }
         *penv = NULL; /* NULL terminate the list */

-- 
1.7.10.2.552.gaa3bb87