Re: [PATCH] infoleak fix1 in signal

From: Oleg Nesterov
Date: Wed May 04 2016 - 06:38:58 EST


On 05/03, Kangjie Lu wrote:
>
> The stack object âinfoâ has a total size of 128 bytes; however,
> only 28 bytes are initialized. The remaining uninitialized bytes
> are sent to userland via send_signal.

Not really, please see copy_siginfo_to_user(), case(__SI_CHLD). All members
copied to user-space are initialized afaics.

> @@ -1594,6 +1594,7 @@ bool do_notify_parent(struct task_struct *tsk, int sig)
> sig = SIGCHLD;
> }
>
> + memset(&info, 0, sizeof(info));

looks like a false alarm to me.

Oleg.