Re: [apparmor] [PATCH] apparmor: fix a memleak in multi_transaction_new()

[John Johansen]

On 8/22/22 18:15, Gaosheng Cui wrote:

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 <cuigaoshe...@huawei.com>

yep, thanks. I will pull this into apparmor-next

Acked-by: John Johansen <john.johan...@canonical.com>

---
  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;

  }