From: Jakub Kicinski <kuba@kernel.org>
Date: Tue, 26 May 2026 15:35:30 +0000 (-0700)
Subject: ethtool: tsinfo: don't pass ERR_PTR to genlmsg_cancel on prepare failure
X-Git-Tag: v7.1-rc6~27^2~6^2~3
X-Git-Url: http://git.ipfire.org/gitweb/index.cgi?a=commitdiff_plain;h=c3fc9976f686f9a95baf87db9d387f218fd65394;p=thirdparty%2Flinux.git

ethtool: tsinfo: don't pass ERR_PTR to genlmsg_cancel on prepare failure

The goto err label leads to:

	genlmsg_cancel(skb, ehdr);
	return ret;

If ethnl_tsinfo_prepare_dump() failed, it has not started a genlmsg.
There's nothing to cancel, and passing an error pointer to
genlmsg_cancel() would cause a crash.

Fixes: b9e3f7dc9ed9 ("net: ethtool: tsinfo: Enhance tsinfo to support several hwtstamp by net topology")
Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Reviewed-by: Kory Maincent <kory.maincent@bootlin.com>
Link: https://patch.msgid.link/20260526153533.2779187-8-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---

diff --git a/net/ethtool/tsinfo.c b/net/ethtool/tsinfo.c
index f54fe6b662b2..14bf01e3b55c 100644
--- a/net/ethtool/tsinfo.c
+++ b/net/ethtool/tsinfo.c
@@ -407,10 +407,8 @@ static int ethnl_tsinfo_dump_one_netdev(struct sk_buff *skb,
 			continue;
 
 		ehdr = ethnl_tsinfo_prepare_dump(skb, dev, reply_data, cb);
-		if (IS_ERR(ehdr)) {
-			ret = PTR_ERR(ehdr);
-			goto err;
-		}
+		if (IS_ERR(ehdr))
+			return PTR_ERR(ehdr);
 
 		reply_data->ts_info.phc_qualifier = ctx->pos_phcqualifier;
 		ret = ops->get_ts_info(dev, &reply_data->ts_info);