linux-kernel - [PATCH 4.19 316/421] smackfs: restrict bytes count in smk_set

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]

Date:   Mon, 19 Jul 2021 16:52:07 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org,
        syzbot <syzbot+77c53db50c9fff774e8e@...kaller.appspotmail.com>,
        Tetsuo Handa <penguin-kernel@...ove.SAKURA.ne.jp>,
        Casey Schaufler <casey@...aufler-ca.com>
Subject: [PATCH 4.19 316/421] smackfs: restrict bytes count in smk_set_cipso()

From: Tetsuo Handa <penguin-kernel@...ove.sakura.ne.jp>

commit 49ec114a6e62d8d320037ce71c1aaf9650b3cafd upstream.

Oops, I failed to update subject line.

>>From 07571157c91b98ce1a4aa70967531e64b78e8346 Mon Sep 17 00:00:00 2001
From: Tetsuo Handa <penguin-kernel@...ove.SAKURA.ne.jp>
Date: Mon, 12 Apr 2021 22:25:06 +0900
Subject: [PATCH 4.19 316/421] smackfs: restrict bytes count in smk_set_cipso()

Commit 7ef4c19d245f3dc2 ("smackfs: restrict bytes count in smackfs write
functions") missed that count > SMK_CIPSOMAX check applies to only
format == SMK_FIXED24_FMT case.

Reported-by: syzbot <syzbot+77c53db50c9fff774e8e@...kaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@...ove.SAKURA.ne.jp>
Signed-off-by: Casey Schaufler <casey@...aufler-ca.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 security/smack/smackfs.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/security/smack/smackfs.c
+++ b/security/smack/smackfs.c
@@ -883,6 +883,8 @@ static ssize_t smk_set_cipso(struct file
 	if (format == SMK_FIXED24_FMT &&
 	    (count < SMK_CIPSOMIN || count > SMK_CIPSOMAX))
 		return -EINVAL;
+	if (count > PAGE_SIZE)
+		return -EINVAL;
 
 	data = memdup_user_nul(buf, count);
 	if (IS_ERR(data))