linux-kernel - Re: [PATCH] make former thread ID available via PTRACE_GETEVENTMSG after PTRACE_EVENT

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <20110608182032.GA16264@redhat.com>
Date:	Wed, 8 Jun 2011 20:20:32 +0200
From:	Oleg Nesterov <oleg@...hat.com>
To:	Denys Vlasenko <vda.linux@...glemail.com>
Cc:	Tejun Heo <tj@...nel.org>, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] make former thread ID available via PTRACE_GETEVENTMSG
	after PTRACE_EVENT_EXEC stop

On 06/08, Denys Vlasenko wrote:
>
> Not sure what kind of locking, if any, I need to put around
> current->parent...

Yes ;)

> @@ -1383,8 +1383,10 @@ int search_binary_handler(struct linux_binprm *bprm,struct pt_regs *regs)
>  			 */
>  			bprm->recursion_depth = depth;
>  			if (retval >= 0) {
> -				if (depth == 0)
> -					tracehook_report_exec(fmt, bprm, regs);
> +				if (depth == 0) {
> +					pid_t pid = task_pid_nr_ns(current, task_active_pid_ns(current->parent));

It is not safe to use ->parent. At least you need rcu lock around.

Also. At this point current has already changed its pid, you should
record pid_t before ->load_binary().

And. We have the coding style police, please use scripts/checkpatch.pl



Just in case, I'll be off-line till Monday.

Oleg.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/