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| 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 14:03:11 +0100 |
| commit | e7a8c57671a1f54902f5ca3545907397ff0c575f (patch) | |
| tree | 24a1101192d5b5639592f000e31454325cdc3a26 /net | |
| parent | bde6afe89ac15ea9bfc3b3483db5d75398066f2b (diff) | |
| download | linux-e7a8c57671a1f54902f5ca3545907397ff0c575f.tar.gz linux-e7a8c57671a1f54902f5ca3545907397ff0c575f.tar.bz2 linux-e7a8c57671a1f54902f5ca3545907397ff0c575f.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 08bb8e09994d..c44ab3b71f3e 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -4192,9 +4192,6 @@ 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); |