From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932736AbZKZEfk (ORCPT ); Wed, 25 Nov 2009 23:35:40 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932306AbZKZEfj (ORCPT ); Wed, 25 Nov 2009 23:35:39 -0500 Received: from mail-ew0-f219.google.com ([209.85.219.219]:46712 "EHLO mail-ew0-f219.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932311AbZKZEfi (ORCPT ); Wed, 25 Nov 2009 23:35:38 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:cc:subject:date:message-id:x-mailer; b=fiYovxtNIUl+2JRMkCcONGzWsAoRRyq5AzGgxs3favhIwSe1OIRgQCQOah6BfXu432 vIIHKfOBUHu9Q2NFtqdQc50zt+Q+oTWXWMu0FzruUAg6pFqcwK33+E1WOoWNnT9Ne3sb 6ef/Ig8Z0n44BSURe6R8T/VLzvyEeiBK2PzW4= From: Frederic Weisbecker To: Ingo Molnar Cc: LKML , Frederic Weisbecker , Steven Rostedt , Prasad Subject: [PATCH 1/3] ksym_tracer: Fix breakpoint removal after modification Date: Thu, 26 Nov 2009 05:35:40 +0100 Message-Id: <1259210142-5714-1-git-send-regression-fweisbec@gmail.com> X-Mailer: git-send-email 1.6.2.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The error path of a breakpoint modification is broken in the ksym tracer. A modified breakpoint hlist node is immediately released after its removal. Also we leak a breakpoint in this case. Fix the path. Signed-off-by: Frederic Weisbecker Cc: Steven Rostedt Cc: Prasad --- kernel/trace/trace_ksym.c | 10 ++++++++-- 1 files changed, 8 insertions(+), 2 deletions(-) diff --git a/kernel/trace/trace_ksym.c b/kernel/trace/trace_ksym.c index 11935b5..9f040e4 100644 --- a/kernel/trace/trace_ksym.c +++ b/kernel/trace/trace_ksym.c @@ -339,14 +339,20 @@ static ssize_t ksym_trace_filter_write(struct file *file, ksym_hbp_handler, true); if (IS_ERR(entry->ksym_hbp)) entry->ksym_hbp = NULL; - if (!entry->ksym_hbp) + + /* modified without problem */ + if (entry->ksym_hbp) { + ret = 0; goto out; + } + } else { + ret = 0; } + /* Error or "symbol:---" case: drop it */ ksym_filter_entry_count--; hlist_del_rcu(&(entry->ksym_hlist)); synchronize_rcu(); kfree(entry); - ret = 0; goto out; } else { /* Check for malformed request: (4) */ -- 1.6.2.3