xcb_auth: Fix memory leak in _xcb_get_auth_info.

If the initial get_peer_sock_name(getpeername ...) succeeds, the
pointer to allocated memory is overwritten by the later call to
get_peer_sock_name(getsockname ...).  Fix that up by freeing
the allocated memory before overwriting the pointer.

Signed-off-by: Nick Bowler <nbowler@draconx.ca>
Signed-off-by: Julien Danjou <julien@danjou.info>

1 files changed, 8 insertions, 3 deletions

diff --git a/src/xcb_auth.c b/src/xcb_auth.c
index 1af27fc..4839b78 100644
--- a/src/xcb_auth.c
+++ b/src/xcb_auth.c
@@ -327,10 +327,15 @@ int _xcb_get_auth_info(int fd, xcb_auth_info_t *info, int display)
     if (!info->namelen)
         goto no_auth;   /* out of memory */
 
-    if (!gotsockname && (sockname = get_peer_sock_name(getsockname, fd)) == NULL)
+    if (!gotsockname)
     {
-        free(info->name);
-        goto no_auth;   /* can only authenticate sockets */
+        free(sockname);
+
+        if ((sockname = get_peer_sock_name(getsockname, fd)) == NULL)
+        {
+            free(info->name);
+            goto no_auth;   /* can only authenticate sockets */
+        }
     }
 
     ret = compute_auth(info, authptr, sockname);