From: Tetsuo Handa penguin-kernel@i-love.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@I-love.SAKURA.ne.jp Date: Mon, 12 Apr 2021 22:25:06 +0900 Subject: [PATCH 4.9 179/245] 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@syzkaller.appspotmail.com Signed-off-by: Tetsuo Handa penguin-kernel@I-love.SAKURA.ne.jp Signed-off-by: Casey Schaufler casey@schaufler-ca.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- security/smack/smackfs.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/security/smack/smackfs.c +++ b/security/smack/smackfs.c @@ -878,6 +878,8 @@ 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))