From: Eyal Birger eyal.birger@gmail.com
stable inclusion from linux-4.19.173 commit 5292ab517275e62042e479aebec9755196643001
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[ Upstream commit 9f8550e4bd9d78a8436c2061ad2530215f875376 ]
The disable_xfrm flag signals that xfrm should not be performed during routing towards a device before reaching device xmit.
For xfrm interfaces this is usually desired as they perform the outbound policy lookup as part of their xmit using their if_id.
Before this change enabling this flag on xfrm interfaces prevented them from xmitting as xfrm_lookup_with_ifid() would not perform a policy lookup in case the original dst had the DST_NOXFRM flag.
This optimization is incorrect when the lookup is done by the xfrm interface xmit logic.
Fix by performing policy lookup when invoked by xfrmi as if_id != 0.
Similarly it's unlikely for the 'no policy exists on net' check to yield any performance benefits when invoked from xfrmi.
Fixes: f203b76d7809 ("xfrm: Add virtual xfrm interfaces") Signed-off-by: Eyal Birger eyal.birger@gmail.com Signed-off-by: Steffen Klassert steffen.klassert@secunet.com Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com
Signed-off-by: Aichun Li liaichun@huawei.com reviewed-by: wangxiaopeng wangxiaopeng7@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com Signed-off-by: Cheng Jian cj.chengjian@huawei.com --- net/xfrm/xfrm_policy.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c index 939f3adf075a..e9aea82f370d 100644 --- a/net/xfrm/xfrm_policy.c +++ b/net/xfrm/xfrm_policy.c @@ -2101,8 +2101,8 @@ struct dst_entry *xfrm_lookup_with_ifid(struct net *net, xflo.flags = flags;
/* To accelerate a bit... */ - if ((dst_orig->flags & DST_NOXFRM) || - !net->xfrm.policy_count[XFRM_POLICY_OUT]) + if (!if_id && ((dst_orig->flags & DST_NOXFRM) || + !net->xfrm.policy_count[XFRM_POLICY_OUT])) goto nopol;
xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id);