diff options
| author | Johannes Wiesböck <johannes.wiesboeck@aisec.fraunhofer.de> | 2025-10-15 22:15:43 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-10-29 13:59:59 +0100 |
| commit | 509da3463fdfe040927f2270f767ca65821a9302 (patch) | |
| tree | 25a135be11cbef58ef342d7d5086afaddef104d9 /net | |
| parent | 4b7140925d9dc642a14d39087d163044c204065b (diff) | |
| download | linux-509da3463fdfe040927f2270f767ca65821a9302.tar.gz linux-509da3463fdfe040927f2270f767ca65821a9302.tar.bz2 linux-509da3463fdfe040927f2270f767ca65821a9302.zip | |
rtnetlink: Allow deleting FDB entries in user namespace
[ Upstream commit bf29555f5bdc017bac22ca66fcb6c9f46ec8788f ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'net')
| -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 3d3743ef4f69..342b92afd121 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -3836,9 +3836,6 @@ 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); |