Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751964AbaF0SPV (ORCPT ); Fri, 27 Jun 2014 14:15:21 -0400 Received: from mx1.redhat.com ([209.132.183.28]:61764 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750990AbaF0SPU (ORCPT ); Fri, 27 Jun 2014 14:15:20 -0400 Date: Fri, 27 Jun 2014 19:01:40 +0200 From: Oleg Nesterov To: Steven Rostedt Cc: Masami Hiramatsu , Namhyung Kim , Srikar Dronamraju , Tom Zanussi , "zhangwei(Jovi)" , linux-kernel@vger.kernel.org Subject: [PATCH 2/4] uprobes: Change unregister/apply to WARN() if uprobe/consumer is gone Message-ID: <20140627170140.GA18322@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140627170116.GA18298@redhat.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add WARN_ON's into uprobe_unregister() and uprobe_apply() to ensure that nobody tries to play with the dead uprobe/consumer. This helps to catch the bugs like the one fixed by the previous patch. In the longer term we should fix this poorly designed interface. uprobe_register() should return "struct uprobe *" which should be passed to apply/unregister. Plus other semantic changes, see the changelog in commit 41ccba029e94. Signed-off-by: Oleg Nesterov --- kernel/events/uprobes.c | 6 +++--- 1 files changed, 3 insertions(+), 3 deletions(-) diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index c445e39..6f3254e 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -846,7 +846,7 @@ static void __uprobe_unregister(struct uprobe *uprobe, struct uprobe_consumer *u { int err; - if (!consumer_del(uprobe, uc)) /* WARN? */ + if (WARN_ON(!consumer_del(uprobe, uc))) return; err = register_for_each_vma(uprobe, NULL); @@ -927,7 +927,7 @@ int uprobe_apply(struct inode *inode, loff_t offset, int ret = -ENOENT; uprobe = find_uprobe(inode, offset); - if (!uprobe) + if (WARN_ON(!uprobe)) return ret; down_write(&uprobe->register_rwsem); @@ -952,7 +952,7 @@ void uprobe_unregister(struct inode *inode, loff_t offset, struct uprobe_consume struct uprobe *uprobe; uprobe = find_uprobe(inode, offset); - if (!uprobe) + if (WARN_ON(!uprobe)) return; down_write(&uprobe->register_rwsem); -- 1.5.5.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/