[PATCH 5.15 01/25] Revert "xfrm: state and policy should fail if XFRMA_IF_ID 0"

Greg Kroah-Hartman
2022-03-17T12:54:43Z

From: Kai Lueke <kailueke@linux.microsoft.com>

commit a3d9001b4e287fc043e5539d03d71a32ab114bcb upstream.

This reverts commit 68ac0f3810e76a853b5f7b90601a05c3048b8b54 because ID
0 was meant to be used for configuring the policy/state without
matching for a specific interface (e.g., Cilium is affected, see
https://github.com/cilium/cilium/pull/18789 and
https://github.com/cilium/cilium/pull/19019).

Signed-off-by: Kai Lueke <kailueke@linux.microsoft.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/xfrm/xfrm_user.c | 21 +++------------------
1 file changed, 3 insertions(+), 18 deletions(-)

--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -629,13 +629,8 @@ static struct xfrm_state *xfrm_state_con

xfrm_smark_init(attrs, &x->props.smark);

- if (attrs[XFRMA_IF_ID]) {
+ if (attrs[XFRMA_IF_ID])
x->if_id = nla_get_u32(attrs[XFRMA_IF_ID]);
- if (!x->if_id) {
- err = -EINVAL;
- goto error;
- }
- }

err = __xfrm_init_state(x, false, attrs[XFRMA_OFFLOAD_DEV]);
if (err)
@@ -1431,13 +1426,8 @@ static int xfrm_alloc_userspi(struct sk_

mark = xfrm_mark_get(attrs, &m);

- if (attrs[XFRMA_IF_ID]) {
+ if (attrs[XFRMA_IF_ID])
if_id = nla_get_u32(attrs[XFRMA_IF_ID]);
- if (!if_id) {
- err = -EINVAL;
- goto out_noput;
- }
- }

if (p->info.seq) {
x = xfrm_find_acq_byseq(net, mark, p->info.seq);
@@ -1750,13 +1740,8 @@ static struct xfrm_policy *xfrm_policy_c

xfrm_mark_get(attrs, &xp->mark);

- if (attrs[XFRMA_IF_ID]) {
+ if (attrs[XFRMA_IF_ID])
xp->if_id = nla_get_u32(attrs[XFRMA_IF_ID]);
- if (!xp->if_id) {
- err = -EINVAL;
- goto error;
- }
- }

return xp;