The SA lookup tuple is (daddr, spi, proto, family, mark), but the EEXIST pre-check and the xfrm_state_insert() vs xfrm_state_add() decision only considered daddr and family, ignoring mark. A migration that only changes the mark inserts a duplicate SA tuple into the hash tables. Before: root@west:~# ip xfrm state add src 10.1.1.1 dst 10.1.1.2 proto esp \ spi 0x1000 reqid 100 mode tunnel aead "rfc4106(gcm(aes))" \ 0x1111111111111111111111111111111111111111 96 \ mark 0x1 mask 0xff root@west:~# ip xfrm state add src 10.1.1.1 dst 10.1.1.2 proto esp \ spi 0x1000 reqid 100 mode tunnel aead "rfc4106(gcm(aes))" \ 0x1111111111111111111111111111111111111111 96 \ mark 0x2 mask 0xff root@west:~# ip xfrm state migrate dst 10.1.1.2 proto esp spi 0x1000 \ mark 0x1 mask 0xff \ new-dst 10.1.1.2 new-src 10.1.1.1 new-reqid 100 \ new-mark 0x2 mask 0xff ip x s src 10.1.1.1 dst 10.1.1.2 proto esp spi 0x00001000 reqid 100 mode tunnel replay-window 0 mark 0x2/0xff aead rfc4106(gcm(aes)) 0x1111111111111111111111111111111111111111 96 anti-replay context: seq 0x0, oseq 0x0, bitmap 0x00000000 src 10.1.1.1 dst 10.1.1.2 proto esp spi 0x00001000 reqid 100 mode tunnel replay-window 0 mark 0x2/0xff aead rfc4106(gcm(aes)) 0x1111111111111111111111111111111111111111 96 anti-replay context: seq 0x0, oseq 0x0, bitmap 0x00000000 sel src 0.0.0.0/0 dst 0.0.0.0/0 Notice two states with same mark 0x2/0xff. After: Error: New SA tuple already occupied. Fixes: a9d155ea9b44 ("xfrm: add XFRM_MSG_MIGRATE_STATE for single SA migration") Reported-by: Sashiko Signed-off-by: Antony Antony --- net/xfrm/xfrm_state.c | 8 +++++--- net/xfrm/xfrm_user.c | 15 ++++++++++----- 2 files changed, 15 insertions(+), 8 deletions(-) diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c index d78cfe481f75..bffe985e42ea 100644 --- a/net/xfrm/xfrm_state.c +++ b/net/xfrm/xfrm_state.c @@ -2221,10 +2221,12 @@ int xfrm_state_migrate_install(const struct xfrm_state *x, struct netlink_ext_ack *extack) { if (m->new_family == m->old_family && - xfrm_addr_equal(&x->id.daddr, &m->new_daddr, m->new_family)) { + xfrm_addr_equal(&x->id.daddr, &m->new_daddr, m->new_family) && + xc->mark.v == x->mark.v && xc->mark.m == x->mark.m) { /* - * Care is needed when the destination address of the state is - * to be updated as it is a part of triplet. + * Care is needed when the destination address or mark of the + * state is to be updated, as they are part of the lookup + * triplet. */ xfrm_state_insert(xc); } else { diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c index 87ef198993db..a2317e6e6802 100644 --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -3435,18 +3435,23 @@ static int xfrm_do_migrate_state(struct sk_buff *skb, struct nlmsghdr *nlh, x->nat_keepalive_interval); if (m.new_family != um->id.family || - !xfrm_addr_equal(&m.new_daddr, &um->id.daddr, um->id.family)) { + !xfrm_addr_equal(&m.new_daddr, &um->id.daddr, um->id.family) || + (m.new_mark && (m.new_mark->v != x->mark.v || + m.new_mark->m != x->mark.m))) { u32 new_mark_key = m.new_mark ? m.new_mark->v & m.new_mark->m : - m.old_mark.v & m.old_mark.m; + x->mark.v & x->mark.m; struct xfrm_state *x_new; x_new = xfrm_state_lookup(net, new_mark_key, &m.new_daddr, um->id.spi, um->id.proto, m.new_family); if (x_new) { xfrm_state_put(x_new); - NL_SET_ERR_MSG(extack, "New SA tuple already occupied"); - err = -EEXIST; - goto out; + if (x_new != x) { + NL_SET_ERR_MSG(extack, "New SA tuple already occupied"); + err = -EEXIST; + goto out; + } + /* self-match via wide mark mask; not a collision */ } } -- 2.47.3