It is better to check the asprintf return value for -1 instead of the

input buffer for NULL.
Found by adding __attribute((__warn_unused_result__)) to asprintf.

OK deraadt@

diff --git a/lib/libfuse/fuse_subr.c b/lib/libfuse/fuse_subr.c
index 2bcb1b6..c0a4f85 100644 (file)
--- a/lib/libfuse/fuse_subr.c
+++ b/lib/libfuse/fuse_subr.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: fuse_subr.c,v 1.8 2014/04/28 13:08:34 syl Exp $ */
+/* $OpenBSD: fuse_subr.c,v 1.9 2015/06/03 19:51:16 reyk Exp $ */
 /*
  * Copyright (c) 2013 Sylvestre Gallon <ccna.syl@gmail.com>
  *
@@ -145,7 +145,7 @@ build_realname(struct fuse *f, ino_t ino)
        struct fuse_vnode *vn;
        char *name = strdup("/");
        char *tmp = NULL;
-       int firstshot = 0;
+       int firstshot = 0, ret;
 
        vn = tree_get(&f->vnode_tree, ino);
        if (!vn || !name) {
@@ -155,11 +155,11 @@ build_realname(struct fuse *f, ino_t ino)
 
        while (vn->parent != 0) {
                if (firstshot++)
-                       asprintf(&tmp, "/%s%s", vn->path, name);
+                       ret = asprintf(&tmp, "/%s%s", vn->path, name);
                else
-                       asprintf(&tmp, "/%s", vn->path);
+                       ret = asprintf(&tmp, "/%s", vn->path);
 
-               if (tmp == NULL) {
+               if (ret == -1) {
                        free(name);
                        return (NULL);
                }