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From: =?utf-8?q?Thomas_Wei=C3=9Fschuh?= <linux@weissschuh.net>
Date: Fri, 15 Mar 2024 17:20:31 +0100
Subject: [PATCH] net: always initialize sysctl ownership
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Message-Id: <20240315-sysctl-net-ownership-v1-1-2b465555a292@weissschuh.net>
To: "David S. Miller" <davem@davemloft.net>, 
 Eric Dumazet <edumazet@google.com>, Jakub Kicinski <kuba@kernel.org>, 
 Paolo Abeni <pabeni@redhat.com>, 
 Dmitry Torokhov <dmitry.torokhov@gmail.com>, 
 "Eric W. Biederman" <ebiederm@xmission.com>
Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, 
 Luis Chamberlain <mcgrof@kernel.org>, 
 Joel Granados <j.granados@samsung.com>, 
 =?utf-8?q?Thomas_Wei=C3=9Fschuh?= <linux@weissschuh.net>

The sysctl core does not initialize these fields when the set_ownership
callback is present.
So always do it in the callback.

Fixes: e79c6a4fc923 ("net: make net namespace sysctls belong to container's owner")
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 net/sysctl_net.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/net/sysctl_net.c b/net/sysctl_net.c
index 051ed5f6fc93..03e320ddacc9 100644
--- a/net/sysctl_net.c
+++ b/net/sysctl_net.c
@@ -62,12 +62,10 @@ static void net_ctl_set_ownership(struct ctl_table_header *head,
 	kgid_t ns_root_gid;
 
 	ns_root_uid = make_kuid(net->user_ns, 0);
-	if (uid_valid(ns_root_uid))
-		*uid = ns_root_uid;
+	*uid = uid_valid(ns_root_uid) ? ns_root_uid : GLOBAL_ROOT_UID;
 
 	ns_root_gid = make_kgid(net->user_ns, 0);
-	if (gid_valid(ns_root_gid))
-		*gid = ns_root_gid;
+	*gid = gid_valid(ns_root_gid) ? ns_root_gid : GLOBAL_ROOT_GID;
 }
 
 static struct ctl_table_root net_sysctl_root = {

---
base-commit: e5eb28f6d1afebed4bb7d740a797d0390bd3a357
change-id: 20240315-sysctl-net-ownership-bc4e17eaeea6

Best regards,
-- 
Thomas Weißschuh <linux@weissschuh.net>