diff options
| author | Jakub Kicinski <kuba@kernel.org> | 2022-05-05 19:51:32 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2022-05-06 12:07:56 +0100 |
| commit | 14d7b8122fd591693a2388b98563707ba72c6780 (patch) | |
| tree | 63d32ba9fafbc94c643b44fb8dca44f98d2ce27a /net/core/rtnetlink.c | |
| parent | 6df6398f7c8b481ce83f28143bc08a5231616deb (diff) | |
net: don't allow user space to lift the device limits
Up until commit 46e6b992c250 ("rtnetlink: allow GSO maximums to
be set on device creation") the gso_max_segs and gso_max_size
of a device were not controlled from user space.
The quoted commit added the ability to control them because of
the following setup:
netns A | netns B
veth<->veth eth0
If eth0 has TSO limitations and user wants to efficiently forward
traffic between eth0 and the veths they should copy the TSO
limitations of eth0 onto the veths. This would happen automatically
for macvlans or ipvlan but veth users are not so lucky (given the
loose coupling).
Unfortunately the commit in question allowed users to also override
the limits on real HW devices.
It may be useful to control the max GSO size and someone may be using
that ability (not that I know of any user), so create a separate set
of knobs to reliably record the TSO limitations. Validate the user
requests.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core/rtnetlink.c')
| -rw-r--r-- | net/core/rtnetlink.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index eea5ed09e1bb..e6d4b9272995 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -2803,7 +2803,7 @@ static int do_setlink(const struct sk_buff *skb, if (tb[IFLA_GSO_MAX_SIZE]) { u32 max_size = nla_get_u32(tb[IFLA_GSO_MAX_SIZE]); - if (max_size > GSO_MAX_SIZE) { + if (max_size > GSO_MAX_SIZE || max_size > dev->tso_max_size) { err = -EINVAL; goto errout; } @@ -2817,7 +2817,7 @@ static int do_setlink(const struct sk_buff *skb, if (tb[IFLA_GSO_MAX_SEGS]) { u32 max_segs = nla_get_u32(tb[IFLA_GSO_MAX_SEGS]); - if (max_segs > GSO_MAX_SEGS) { + if (max_segs > GSO_MAX_SEGS || max_segs > dev->tso_max_segs) { err = -EINVAL; goto errout; } |