[PATCH 6.0 0553/1073] apparmor: fix a memleak in multi_transaction_new()

Greg Kroah-Hartman
2022-12-28T16:07:19Z

From: Gaosheng Cui <cuigaosheng1@huawei.com>

[ 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>
---
security/apparmor/apparmorfs.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c
index d066ccc219e2..7160e7aa58b9 100644
--- a/security/apparmor/apparmorfs.c
+++ b/security/apparmor/apparmorfs.c
@@ -868,8 +868,10 @@ 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;
}
--
2.35.1