Re: [PATCH] file capabilities: allow sigcont within session (v2)

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

[kernel/signal.c:check_kill_permission() could probably benefit from
getting more consistently indented!]

I'm not sure I can grok your comment. Did you mean:

  /* as per, check_kill_permission(), permit if tasks have same uid */

As to content:

Signed-off-by: Andrew G. Morgan <[email protected]>

Cheers

Andrew

Serge E. Hallyn wrote:
>>From 5bff8967f45a35f858b96ca673d9bf98eac53d49 Mon Sep 17 00:00:00 2001
> From: Serge E. Hallyn <[email protected]>
> Date: Wed, 31 Oct 2007 11:22:04 -0500
> Subject: [PATCH 1/1] file capabilities: allow sigcont within session (v2)
> 
> (This is a proposed fix to http://bugzilla.kernel.org/show_bug.cgi?id=9247)
> 
> Allow sigcont to be sent to a process with greater capabilities
> if it is in the same session.  Otherwise, a shell from which
> I've started a root shell and done 'suspend' can't be restarted
> by the parent shell.
> 
> Also don't do file-capabilities signaling checks when uids for
> the processes don't match, since the standard check_kill_permission
> will have done those checks.
> 
> Signed-off-by: Serge E. Hallyn <[email protected]>
> ---
>  security/commoncap.c |    9 +++++++++
>  1 files changed, 9 insertions(+), 0 deletions(-)
> 
> diff --git a/security/commoncap.c b/security/commoncap.c
> index bf67871..4de6857 100644
> --- a/security/commoncap.c
> +++ b/security/commoncap.c
> @@ -526,6 +526,15 @@ int cap_task_kill(struct task_struct *p, struct siginfo *info,
>  	if (info != SEND_SIG_NOINFO && (is_si_special(info) || SI_FROMKERNEL(info)))
>  		return 0;
>  
> +	/* if tasks have same uid, then check_kill_permission did check */
> +	if (current->uid == p->uid || current->euid == p->uid ||
> +		current->uid == p->suid || current->euid == p->suid)
> +		return 0;
> +
> +	/* sigcont is permitted within same session */
> +	if (sig == SIGCONT && (task_session_nr(current)==task_session_nr(p)))
> +		return 0;
> +
>  	if (secid)
>  		/*
>  		 * Signal sent as a particular user.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.6 (GNU/Linux)

iD8DBQFHKVpRQheEq9QabfIRAnp9AKCZHb526eioQWKycH7V7LfcHP7VvQCdG0AJ
QTVOLvQ2hip+j2qZ1mb2Y6w=
=45et
-----END PGP SIGNATURE-----
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux