From: Jakub Kicinski <kuba@kernel.org>
Date: Tue, 14 Dec 2021 15:47:25 +0000 (-0800)
Subject: ethtool: always write dev in ethnl_parse_header_dev_get
X-Git-Tag: v6.1-rc5~2306^2~179
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=3bc14ea0d12a57a968038f8e86e9bc2c1668ad9a;p=platform%2Fkernel%2Flinux-starfive.git

ethtool: always write dev in ethnl_parse_header_dev_get

Commit 0976b888a150 ("ethtool: fix null-ptr-deref on ref tracker")
made the write to req_info.dev conditional, but as Eric points out
in a different follow up the structure is often allocated on the
stack and not kzalloc()'d so seems safer to always write the dev,
in case it's garbage on input.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c
index 767fb3f..f09c623 100644
--- a/net/ethtool/netlink.c
+++ b/net/ethtool/netlink.c
@@ -141,10 +141,9 @@ int ethnl_parse_header_dev_get(struct ethnl_req_info *req_info,
 		return -EINVAL;
 	}
 
-	if (dev) {
-		req_info->dev = dev;
+	req_info->dev = dev;
+	if (dev)
 		netdev_tracker_alloc(dev, &req_info->dev_tracker, GFP_KERNEL);
-	}
 	req_info->flags = flags;
 	return 0;
 }