Date:   Fri, 24 Dec 2021 14:34:27 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Jiasheng Jiang <jiasheng@iscas.ac.cn>
Cc:     jmaloy@redhat.com, ying.xue@windriver.com, davem@davemloft.net,
        netdev@vger.kernel.org, tipc-discussion@lists.sourceforge.net,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] net/tipc: Check null mem pointer
Message-ID: <20211224143427.6aeebb8f@kicinski-fedora-PC1C0HJN.hsd1.ca.comcast.net>
In-Reply-To: <20211224074646.1588903-1-jiasheng@iscas.ac.cn>
References: <20211224074646.1588903-1-jiasheng@iscas.ac.cn>
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Precedence: bulk

On Fri, 24 Dec 2021 15:46:46 +0800 Jiasheng Jiang wrote:
> For the possible alloc failure of the kmemdup(), it may return null
> pointer.
> Therefore, the returned pointer should be checked to guarantee the
> success of the init.
> 
> Fixes: fc1b6d6de220 ("tipc: introduce TIPC encryption & authentication")
> Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
> ---
>  net/tipc/crypto.c | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/net/tipc/crypto.c b/net/tipc/crypto.c
> index c9391d38de85..19015e08e750 100644
> --- a/net/tipc/crypto.c
> +++ b/net/tipc/crypto.c
> @@ -596,7 +596,14 @@ static int tipc_aead_init(struct tipc_aead **aead, struct tipc_aead_key *ukey,
>  	tmp->mode = mode;
>  	tmp->cloned = NULL;
>  	tmp->authsize = TIPC_AES_GCM_TAG_SIZE;
> +
>  	tmp->key = kmemdup(ukey, tipc_aead_key_size(ukey), GFP_KERNEL);
> +	if (!tmp->key) {
> +		free_percpu(tmp->tfm_entry);
> +		kfree_sensitive(tmp);
> +		return -ENOMEM;
> +	}
> +
>  	memcpy(&tmp->salt, ukey->key + keylen, TIPC_AES_GCM_SALT_SIZE);
>  	atomic_set(&tmp->users, 0);
>  	atomic64_set(&tmp->seqno, 0);

Fixed over a month ago 3e6db079751a ("tipc: check for null after calling
kmemdup")