linux-kernel - [PATCH 3.16 146/254] tracing: Fix possible double free on failure of allocating trace buffer

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

Message-ID: <lsq.1519831218.419844661@decadent.org.uk>
Date:   Wed, 28 Feb 2018 15:20:18 +0000
From:   Ben Hutchings <ben@...adent.org.uk>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
CC:     akpm@...ux-foundation.org,
        "Steven Rostedt (VMware)" <rostedt@...dmis.org>,
        "Chunyan Zhang" <chunyan.zhang@...eadtrum.com>,
        "Jing Xia" <jing.xia@...eadtrum.com>
Subject: [PATCH 3.16 146/254] tracing: Fix possible double free on failure
 of allocating trace buffer

3.16.55-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: "Steven Rostedt (VMware)" <rostedt@...dmis.org>

commit 4397f04575c44e1440ec2e49b6302785c95fd2f8 upstream.

Jing Xia and Chunyan Zhang reported that on failing to allocate part of the
tracing buffer, memory is freed, but the pointers that point to them are not
initialized back to NULL, and later paths may try to free the freed memory
again. Jing and Chunyan fixed one of the locations that does this, but
missed a spot.

Link: http://lkml.kernel.org/r/20171226071253.8968-1-chunyan.zhang@spreadtrum.com

Fixes: 737223fbca3b1 ("tracing: Consolidate buffer allocation code")
Reported-by: Jing Xia <jing.xia@...eadtrum.com>
Reported-by: Chunyan Zhang <chunyan.zhang@...eadtrum.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@...dmis.org>
Signed-off-by: Ben Hutchings <ben@...adent.org.uk>
---
 kernel/trace/trace.c | 1 +
 1 file changed, 1 insertion(+)

--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -6220,6 +6220,7 @@ allocate_trace_buffer(struct trace_array
 	buf->data = alloc_percpu(struct trace_array_cpu);
 	if (!buf->data) {
 		ring_buffer_free(buf->buffer);
+		buf->buffer = NULL;
 		return -ENOMEM;
 	}