On Tue, Nov 12, 2013 at 02:46:03PM +0100, Hannes Frederic Sowa wrote: > > It is needed by fork to set up the stack canary. And this actually gets > > called before the secret is initialized. > > Maybe we could use this for the time being and use the seeding method > of kaslr as soon as it hits the tree? Hmm, from what I can tell even early_initcall() is going to be early enough. The stack canary is set up by boot_init_stack_canary(), which is run very, very early in start_kerne() --- way before early_initcalls, or even before interrupts are enabled. So adding random_int_secret_init_early() as a core_initcall is still too late. I wonder if we need to do something in common with what Kees has been considering for the kaslr code, since it's a similar issue --- we need random number way earlier than we can really afford to initialize /dev/random. - Ted P.S. Unless I'm missing something (and I hope I am), it would appear that the stack canary is going to easily predictable by an attacker on non-x86 platforms that don't have RDRAND. Has someone tested whether or not the stack canary isn't constant across ARM or pre-Sandy Bridge x86 systems? -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
