diff options
| author | Johannes Wiesböck <johannes.wiesboeck@aisec.fraunhofer.de> | 2025-10-15 22:15:43 +0200 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-10-16 16:09:56 -0700 |
| commit | bf29555f5bdc017bac22ca66fcb6c9f46ec8788f (patch) | |
| tree | a81c4f12fdf7f612138ee40a2225267cceb7b711 | |
| parent | 1b0124ad5039678a9dfafb6aafef6f430a246b91 (diff) | |
rtnetlink: Allow deleting FDB entries in user namespace
Creating FDB entries is possible from a non-initial user namespace when
having CAP_NET_ADMIN, yet, when deleting FDB entries, processes receive
an EPERM because the capability is always checked against the initial
user namespace. This restricts the FDB management from unprivileged
containers.
Drop the netlink_capable check in rtnl_fdb_del as it was originally
dropped in c5c351088ae7 and reintroduced in 1690be63a27b without
intention.
This patch was tested using a container on GyroidOS, where it was
possible to delete FDB entries from an unprivileged user namespace and
private network namespace.
Fixes: 1690be63a27b ("bridge: Add vlan support to static neighbors")
Reviewed-by: Michael Weiß <michael.weiss@aisec.fraunhofer.de>
Tested-by: Harshal Gohel <hg@simonwunderlich.de>
Signed-off-by: Johannes Wiesböck <johannes.wiesboeck@aisec.fraunhofer.de>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20251015201548.319871-1-johannes.wiesboeck@aisec.fraunhofer.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | net/core/rtnetlink.c | 3 |
1 files changed, 0 insertions, 3 deletions
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 8040ff7c356e..576d5ec3bb36 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -4715,9 +4715,6 @@ static int rtnl_fdb_del(struct sk_buff *skb, struct nlmsghdr *nlh, int err; u16 vid; - if (!netlink_capable(skb, CAP_NET_ADMIN)) - return -EPERM; - if (!del_bulk) { err = nlmsg_parse_deprecated(nlh, sizeof(*ndm), tb, NDA_MAX, NULL, extack); |