Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Navid Emamdoost <navid.emamdoost@gmail.com>
To:     josef@toxicpanda.com
Cc:     kjlu@umn.edu, smccaman@umn.edu, secalert@redhat.com,
        emamd001@umn.edu, Navid Emamdoost <navid.emamdoost@gmail.com>,
        Jens Axboe <axboe@kernel.dk>, linux-block@vger.kernel.org,
        nbd@other.debian.org, linux-kernel@vger.kernel.org
Subject: [PATCH v2] nbd_genl_status: null check for nla_nest_start
Date:   Mon, 29 Jul 2019 11:42:26 -0500
Message-Id: <20190729164226.22632-1-navid.emamdoost@gmail.com>
In-Reply-To: <20190729130912.7imtg3hfnvb4lt2y@MacBook-Pro-91.local>
References: <20190729130912.7imtg3hfnvb4lt2y@MacBook-Pro-91.local>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

nla_nest_start may fail and return NULL. The check is inserted, and
errno is selected based on other call sites within the same source code.
Update: removed extra new line.

Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
---
 drivers/block/nbd.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 9bcde2325893..2410812d1e82 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -2149,6 +2149,11 @@ static int nbd_genl_status(struct sk_buff *skb, struct genl_info *info)
 	}
 
 	dev_list = nla_nest_start_noflag(reply, NBD_ATTR_DEVICE_LIST);
+	if (!dev_list) {
+		ret = -EMSGSIZE;
+		goto out;
+	}
+
 	if (index == -1) {
 		ret = idr_for_each(&nbd_index_idr, &status_cb, reply);
 		if (ret) {
-- 
2.17.1