On 03/07, Lucas De Marchi wrote: > > On Thu, Mar 7, 2013 at 4:37 PM, Oleg Nesterov <o...@redhat.com> wrote: > > > >> @@ -98,12 +93,13 @@ static int call_modprobe(char *module_name, int wait) > >> argv[3] = module_name; /* check free_modprobe_argv() */ > >> argv[4] = NULL; > >> > >> - return call_usermodehelper_fns(modprobe_path, argv, envp, > >> - wait | UMH_KILLABLE, NULL, free_modprobe_argv, NULL); > >> + ret = call_usermodehelper(modprobe_path, argv, envp, > >> + wait | UMH_KILLABLE); > >> + kfree(module_name); > > > > Please note UMH_KILLABLE. call_usermodehelper() can be interrupted > > and even UMH_WAIT_EXEC case is not safe. If call_modprobe() is killed > > we can return while the workqueue thread still tries to clone/exec/etc. > > Even if it's killed, we would just free the resource we allocated > before.
Yes, and after that ____call_usermodehelper() can do do_execve(module_name) ? > It would not be safe if we allocated in the init function and > freed in the cleanup. But we do? We free this memory in cleanup ? And I was allocated by us. sub_info itself can't go away (if you meant this), but sub_info->path/argv/envp can. > Or am I missing something? Or me... Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
