do_coredump() accesses helper_argv[0] without checking helper_argv !=
NULL.  This can happen if page allocation failed.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 
        if (ispipe) {
                helper_argv = argv_split(GFP_KERNEL, corename+1, &helper_argc);
+               if (!helper_argv) {
+                       printk(KERN_WARNING "%s failed to allocate memory\n",
+                              __func__);
+                       goto fail_unlock;
+               }
                /* Terminate the string before the first option */
                delimit = strchr(corename, ' ');
                if (delimit)