From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E1CDBC433F5 for ; Sat, 16 Oct 2021 03:03:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C488861222 for ; Sat, 16 Oct 2021 03:03:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239723AbhJPDFE (ORCPT ); Fri, 15 Oct 2021 23:05:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:42082 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239627AbhJPDFB (ORCPT ); Fri, 15 Oct 2021 23:05:01 -0400 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id DE0DD60F59; Sat, 16 Oct 2021 03:02:53 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.94.2) (envelope-from ) id 1mbZyG-006ZSF-8Y; Fri, 15 Oct 2021 23:02:52 -0400 Message-ID: <20211016030252.100986733@goodmis.org> User-Agent: quilt/0.66 Date: Fri, 15 Oct 2021 23:02:24 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Vamshi K Sthambamkadi Subject: [for-linus][PATCH 2/7] tracing: Fix memory leak in eprobe_register() References: <20211016030222.926060517@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Vamshi K Sthambamkadi kmemleak report: unreferenced object 0xffff900a70ec7ec0 (size 32): comm "ftracetest", pid 2770, jiffies 4295042510 (age 311.464s) hex dump (first 32 bytes): c8 31 23 45 0a 90 ff ff 40 85 c7 6e 0a 90 ff ff .1#E....@..n.... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<000000009d3751fd>] kmem_cache_alloc_trace+0x2a2/0x440 [<0000000088b8124b>] eprobe_register+0x1e3/0x350 [<000000002a9a0517>] __ftrace_event_enable_disable+0x7c/0x240 [<0000000019109321>] event_enable_write+0x93/0xe0 [<000000007d85b320>] vfs_write+0xb9/0x260 [<00000000b94c5e41>] ksys_write+0x67/0xe0 [<000000005a08c81d>] __x64_sys_write+0x1a/0x20 [<00000000240bf576>] do_syscall_64+0x3b/0xc0 [<0000000043d5d9f6>] entry_SYSCALL_64_after_hwframe+0x44/0xae unreferenced object 0xffff900a56bbf280 (size 128): comm "ftracetest", pid 2770, jiffies 4295042510 (age 311.464s) hex dump (first 32 bytes): ff ff ff ff ff ff ff ff 00 00 00 00 01 00 00 00 ................ 80 69 3b b2 ff ff ff ff 20 69 3b b2 ff ff ff ff .i;..... i;..... backtrace: [<000000009d3751fd>] kmem_cache_alloc_trace+0x2a2/0x440 [<00000000c4e90fad>] eprobe_register+0x1fc/0x350 [<000000002a9a0517>] __ftrace_event_enable_disable+0x7c/0x240 [<0000000019109321>] event_enable_write+0x93/0xe0 [<000000007d85b320>] vfs_write+0xb9/0x260 [<00000000b94c5e41>] ksys_write+0x67/0xe0 [<000000005a08c81d>] __x64_sys_write+0x1a/0x20 [<00000000240bf576>] do_syscall_64+0x3b/0xc0 [<0000000043d5d9f6>] entry_SYSCALL_64_after_hwframe+0x44/0xae In new_eprobe_trigger(), allocated edata and trigger variables are never freed. To fix, free memory in disable_eprobe(). Link: https://lkml.kernel.org/r/20211008071802.GA2098@cosmos Fixes: 7491e2c442781 ("tracing: Add a probe that attaches to trace events") Signed-off-by: Vamshi K Sthambamkadi Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_eprobe.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c index 3044b762cbd7..570d081929fb 100644 --- a/kernel/trace/trace_eprobe.c +++ b/kernel/trace/trace_eprobe.c @@ -632,6 +632,13 @@ static int disable_eprobe(struct trace_eprobe *ep, trace_event_trigger_enable_disable(file, 0); update_cond_flag(file); + + /* Make sure nothing is using the edata or trigger */ + tracepoint_synchronize_unregister(); + + kfree(edata); + kfree(trigger); + return 0; } -- 2.32.0