[PATCH 5.10 16/52] ipv4: Fix NULL vs error pointer check in inet_blackhole_dev_init()

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

5.10-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Dan Carpenter <dan.carpenter@linaro.org>

[ Upstream commit a51160f8da850a65afbf165f5bbac7ffb388bf74 ]

The inetdev_init() function never returns NULL.  Check for error
pointers instead.

Fixes: 22600596b675 ("ipv4: give an IPv4 dev to blackhole_netdev")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/aLaQWL9NguWmeM1i@stanley.mountain
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/ipv4/devinet.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index 2dc94109fc0ea..bf85978145197 100644
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -332,14 +332,13 @@ static void inetdev_destroy(struct in_device *in_dev)
 
 static int __init inet_blackhole_dev_init(void)
 {
-	int err = 0;
+	struct in_device *in_dev;
 
 	rtnl_lock();
-	if (!inetdev_init(blackhole_netdev))
-		err = -ENOMEM;
+	in_dev = inetdev_init(blackhole_netdev);
 	rtnl_unlock();
 
-	return err;
+	return PTR_ERR_OR_ZERO(in_dev);
 }
 late_initcall(inet_blackhole_dev_init);
 
-- 
2.50.1