From: Gaosheng Cui <cuigaosheng1@huawei.com>
Date: Tue, 23 Aug 2022 01:15:03 +0000 (+0800)
Subject: apparmor: fix a memleak in multi_transaction_new()
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=775a37ffa9f4681c4ad84c8634a7eec8af7098d4;p=linux.git

apparmor: fix a memleak in multi_transaction_new()

[ Upstream commit c73275cf6834787ca090317f1d20dbfa3b7f05aa ]

In multi_transaction_new(), the variable t is not freed or passed out
on the failure of copy_from_user(t->data, buf, size), which could lead
to a memleak.

Fix this bug by adding a put_multi_transaction(t) in the error path.

Fixes: 1dea3b41e84c5 ("apparmor: speed up transactional queries")
Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c
index a891705b1d577..8c7719108d7f7 100644
--- a/security/apparmor/apparmorfs.c
+++ b/security/apparmor/apparmorfs.c
@@ -867,8 +867,10 @@ static struct multi_transaction *multi_transaction_new(struct file *file,
 	if (!t)
 		return ERR_PTR(-ENOMEM);
 	kref_init(&t->count);
-	if (copy_from_user(t->data, buf, size))
+	if (copy_from_user(t->data, buf, size)) {
+		put_multi_transaction(t);
 		return ERR_PTR(-EFAULT);
+	}
 
 	return t;
 }