libmultipath: _install_keyword cleanup

_install_keyword should use VECTOR_LAST_SLOT(), which has better error
checking. It should also fail if it gets a NULL pointer, instead of
dereferencing it. Found by coverity.

Reviewed-by: Martin Wilck <mwilck@suse.com>
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>

diff --git a/libmultipath/parser.c b/libmultipath/parser.c
index b8b7e0d..92ef7cf 100644 (file)
--- a/libmultipath/parser.c
+++ b/libmultipath/parser.c
@@ -79,12 +79,16 @@ _install_keyword(vector keywords, char *string,
        struct keyword *keyword;
 
        /* fetch last keyword */
-       keyword = VECTOR_SLOT(keywords, VECTOR_SIZE(keywords) - 1);
+       keyword = VECTOR_LAST_SLOT(keywords);
+       if (!keyword)
+               return 1;
 
        /* position to last sub level */
-       for (i = 0; i < sublevel; i++)
-               keyword =
-                   VECTOR_SLOT(keyword->sub, VECTOR_SIZE(keyword->sub) - 1);
+       for (i = 0; i < sublevel; i++) {
+               keyword = VECTOR_LAST_SLOT(keyword->sub);
+               if (!keyword)
+                       return 1;
+       }
 
        /* First sub level allocation */
        if (!keyword->sub)