From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932903Ab2AXCs6 (ORCPT ); Mon, 23 Jan 2012 21:48:58 -0500 Received: from cantor2.suse.de ([195.135.220.15]:50661 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932888Ab2AXCsy (ORCPT ); Mon, 23 Jan 2012 21:48:54 -0500 X-Mailbox-Line: From gregkh@clark.kroah.org Mon Jan 23 18:39:34 2012 Message-Id: <20120124023934.876339419@clark.kroah.org> User-Agent: quilt/0.50-11.1 Date: Mon, 23 Jan 2012 18:35:43 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Jim Keniston , Ananth N Mavinakayanahalli , Masami Hiramatsu , Srinivasa D S Subject: [123/129] kprobes: initialize before using a hlist In-Reply-To: <20120124024041.GA18422@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ Content-Length: 1477 Lines: 43 From: Ananth N Mavinakayanahalli commit d496aab567e7e52b3e974c9192a5de6e77dce32c upstream. Commit ef53d9c5e ("kprobes: improve kretprobe scalability with hashed locking") introduced a bug where we can potentially leak kretprobe_instances since we initialize a hlist head after having used it. Initialize the hlist head before using it. Reported by: Jim Keniston Acked-by: Jim Keniston Signed-off-by: Ananth N Mavinakayanahalli Acked-by: Masami Hiramatsu Cc: Srinivasa D S Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- kernel/kprobes.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1077,6 +1077,7 @@ void __kprobes kprobe_flush_task(struct /* Early boot. kretprobe_table_locks not yet initialized. */ return; + INIT_HLIST_HEAD(&empty_rp); hash = hash_ptr(tk, KPROBE_HASH_BITS); head = &kretprobe_inst_table[hash]; kretprobe_table_lock(hash, &flags); @@ -1085,7 +1086,6 @@ void __kprobes kprobe_flush_task(struct recycle_rp_inst(ri, &empty_rp); } kretprobe_table_unlock(hash, &flags); - INIT_HLIST_HEAD(&empty_rp); hlist_for_each_entry_safe(ri, node, tmp, &empty_rp, hlist) { hlist_del(&ri->hlist); kfree(ri);