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* [PATCH] signal: stop info leak via the tkill and the tgkill syscalls
@ 2013-04-17 19:19 Kees Cook
  2013-04-20 22:14 ` Serge E. Hallyn
  0 siblings, 1 reply; 3+ messages in thread
From: Kees Cook @ 2013-04-17 19:19 UTC (permalink / raw)
  To: linux-kernel
  Cc: Al Viro, Oleg Nesterov, Andrew Morton, Eric W. Biederman,
	Serge Hallyn, PaX Team, Kees Cook, Emese Revfy, stable

From: Emese Revfy <re.emese@gmail.com>

This fixes a kernel memory contents leak via the tkill and tgkill syscalls
for compat processes.

This is visible in the siginfo_t->_sifields._rt.si_sigval.sival_ptr field
when handling signals delivered from tkill.

The place of the infoleak:

int copy_siginfo_to_user32(compat_siginfo_t __user *to, siginfo_t *from)
{
        ...
        put_user_ex(ptr_to_compat(from->si_ptr), &to->si_ptr);
        ...
}

Signed-off-by: Emese Revfy <re.emese@gmail.com>
Reviewed-by: PaX Team <pageexec@freemail.hu>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
---
 kernel/signal.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/signal.c b/kernel/signal.c
index dd72567..598dc06 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -2948,7 +2948,7 @@ do_send_specific(pid_t tgid, pid_t pid, int sig, struct siginfo *info)
 
 static int do_tkill(pid_t tgid, pid_t pid, int sig)
 {
-	struct siginfo info;
+	struct siginfo info = {};
 
 	info.si_signo = sig;
 	info.si_errno = 0;
-- 
1.7.9.5


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH] signal: stop info leak via the tkill and the tgkill syscalls
  2013-04-17 19:19 [PATCH] signal: stop info leak via the tkill and the tgkill syscalls Kees Cook
@ 2013-04-20 22:14 ` Serge E. Hallyn
  2013-04-20 22:29   ` Eric W. Biederman
  0 siblings, 1 reply; 3+ messages in thread
From: Serge E. Hallyn @ 2013-04-20 22:14 UTC (permalink / raw)
  To: Kees Cook
  Cc: linux-kernel, Al Viro, Oleg Nesterov, Andrew Morton,
	Eric W. Biederman, Serge Hallyn, PaX Team, Emese Revfy, stable

Quoting Kees Cook (keescook@chromium.org):
> From: Emese Revfy <re.emese@gmail.com>
> 
> This fixes a kernel memory contents leak via the tkill and tgkill syscalls
> for compat processes.
> 
> This is visible in the siginfo_t->_sifields._rt.si_sigval.sival_ptr field
> when handling signals delivered from tkill.
> 
> The place of the infoleak:
> 
> int copy_siginfo_to_user32(compat_siginfo_t __user *to, siginfo_t *from)
> {
>         ...
>         put_user_ex(ptr_to_compat(from->si_ptr), &to->si_ptr);
>         ...
> }
> 
> Signed-off-by: Emese Revfy <re.emese@gmail.com>

Sorry, not sure if this is applied yet,

Acked-by: Serge Hallyn <serge.hallyn@canonical.com>

> Reviewed-by: PaX Team <pageexec@freemail.hu>
> Signed-off-by: Kees Cook <keescook@chromium.org>
> Cc: stable@vger.kernel.org
> ---
>  kernel/signal.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/kernel/signal.c b/kernel/signal.c
> index dd72567..598dc06 100644
> --- a/kernel/signal.c
> +++ b/kernel/signal.c
> @@ -2948,7 +2948,7 @@ do_send_specific(pid_t tgid, pid_t pid, int sig, struct siginfo *info)
>  
>  static int do_tkill(pid_t tgid, pid_t pid, int sig)
>  {
> -	struct siginfo info;
> +	struct siginfo info = {};
>  
>  	info.si_signo = sig;
>  	info.si_errno = 0;
> -- 
> 1.7.9.5
> 
> --
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^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH] signal: stop info leak via the tkill and the tgkill syscalls
  2013-04-20 22:14 ` Serge E. Hallyn
@ 2013-04-20 22:29   ` Eric W. Biederman
  0 siblings, 0 replies; 3+ messages in thread
From: Eric W. Biederman @ 2013-04-20 22:29 UTC (permalink / raw)
  To: Serge E. Hallyn
  Cc: Kees Cook, linux-kernel, Al Viro, Oleg Nesterov, Andrew Morton,
	Serge Hallyn, PaX Team, Emese Revfy, stable

"Serge E. Hallyn" <serge@hallyn.com> writes:

>
> Sorry, not sure if this is applied yet,
>
> Acked-by: Serge Hallyn <serge.hallyn@canonical.com>

I am pretty certain I saw Andrew apply this one and I have already seen
the stable back from gregkh go past.

Eric

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2013-04-20 22:29 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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2013-04-17 19:19 [PATCH] signal: stop info leak via the tkill and the tgkill syscalls Kees Cook
2013-04-20 22:14 ` Serge E. Hallyn
2013-04-20 22:29   ` Eric W. Biederman

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