linux-kernel - [PATCH 3.16 192/306] mei: bus: fix received data size check in NFC fixup

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.1487198500.816660536@decadent.org.uk>
Date:   Wed, 15 Feb 2017 22:41:40 +0000
From:   Ben Hutchings <ben@...adent.org.uk>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
CC:     akpm@...ux-foundation.org,
        "Tomas Winkler" <tomas.winkler@...el.com>,
        "Greg Kroah-Hartman" <gregkh@...uxfoundation.org>,
        "Alexander Usyskin" <alexander.usyskin@...el.com>
Subject: [PATCH 3.16 192/306] mei: bus: fix received data size check in
 NFC fixup

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

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

From: Alexander Usyskin <alexander.usyskin@...el.com>

commit 582ab27a063a506ccb55fc48afcc325342a2deba upstream.

NFC version reply size checked against only header size, not against
full message size. That may lead potentially to uninitialized memory access
in version data.

That leads to warnings when version data is accessed:
drivers/misc/mei/bus-fixup.c: warning: '*((void *)&ver+11)' may be used uninitialized in this function [-Wuninitialized]:  => 212:2

Reported in
Build regressions/improvements in v4.9-rc3
https://lkml.org/lkml/2016/10/30/57

Fixes: 59fcd7c63abf (mei: nfc: Initial nfc implementation)
Signed-off-by: Alexander Usyskin <alexander.usyskin@...el.com>
Signed-off-by: Tomas Winkler <tomas.winkler@...el.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
[bwh: Backported to 3.16:
 - Drop change in mei_phy.c
 - Adjust filename]
Signed-off-by: Ben Hutchings <ben@...adent.org.uk>
---
--- a/drivers/misc/mei/nfc.c
+++ b/drivers/misc/mei/nfc.c
@@ -292,7 +292,7 @@ static int mei_nfc_if_version(struct mei
 		return -ENOMEM;
 
 	bytes_recv = __mei_cl_recv(cl, (u8 *)reply, if_version_length);
-	if (bytes_recv < 0 || bytes_recv < sizeof(struct mei_nfc_reply)) {
+	if (bytes_recv < if_version_length) {
 		dev_err(&dev->pdev->dev, "Could not read IF version\n");
 		ret = -EIO;
 		goto err;