From: Florian Westphal fw@strlen.de
[ Upstream commit ea1300b9df7c8e8b65695a08b8f6aaf4b25fec9c ]
mptcp_token_get_sock() may return a mptcp socket that is in a different net namespace than the socket that received the token value.
The mptcp syncookie code path had an explicit check for this, this moves the test into mptcp_token_get_sock() function.
Eventually token.c should be converted to pernet storage, but such change is not suitable for net tree.
Fixes: 2c5ebd001d4f0 ("mptcp: refactor token container") Signed-off-by: Florian Westphal fw@strlen.de Signed-off-by: Mat Martineau mathew.j.martineau@linux.intel.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- net/mptcp/mptcp_diag.c | 2 +- net/mptcp/protocol.h | 2 +- net/mptcp/subflow.c | 2 +- net/mptcp/syncookies.c | 13 +------------ net/mptcp/token.c | 11 ++++++++--- net/mptcp/token_test.c | 14 ++++++++------ 6 files changed, 20 insertions(+), 24 deletions(-)
diff --git a/net/mptcp/mptcp_diag.c b/net/mptcp/mptcp_diag.c index 5f390a97f556..f1af3f44875e 100644 --- a/net/mptcp/mptcp_diag.c +++ b/net/mptcp/mptcp_diag.c @@ -36,7 +36,7 @@ static int mptcp_diag_dump_one(struct netlink_callback *cb, struct sock *sk;
net = sock_net(in_skb->sk); - msk = mptcp_token_get_sock(req->id.idiag_cookie[0]); + msk = mptcp_token_get_sock(net, req->id.idiag_cookie[0]); if (!msk) goto out_nosk;
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index 13ab89dc1914..3e5af8397434 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -424,7 +424,7 @@ int mptcp_token_new_connect(struct sock *sk); void mptcp_token_accept(struct mptcp_subflow_request_sock *r, struct mptcp_sock *msk); bool mptcp_token_exists(u32 token); -struct mptcp_sock *mptcp_token_get_sock(u32 token); +struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token); struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot, long *s_num); void mptcp_token_destroy(struct mptcp_sock *msk); diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index bba5696fee36..2e9238490924 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -69,7 +69,7 @@ static struct mptcp_sock *subflow_token_join_request(struct request_sock *req, struct mptcp_sock *msk; int local_id;
- msk = mptcp_token_get_sock(subflow_req->token); + msk = mptcp_token_get_sock(sock_net(req_to_sk(req)), subflow_req->token); if (!msk) { SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINNOTOKEN); return NULL; diff --git a/net/mptcp/syncookies.c b/net/mptcp/syncookies.c index 37127781aee9..7f22526346a7 100644 --- a/net/mptcp/syncookies.c +++ b/net/mptcp/syncookies.c @@ -108,18 +108,12 @@ bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subfl
e->valid = 0;
- msk = mptcp_token_get_sock(e->token); + msk = mptcp_token_get_sock(net, e->token); if (!msk) { spin_unlock_bh(&join_entry_locks[i]); return false; }
- /* If this fails, the token got re-used in the mean time by another - * mptcp socket in a different netns, i.e. entry is outdated. - */ - if (!net_eq(sock_net((struct sock *)msk), net)) - goto err_put; - subflow_req->remote_nonce = e->remote_nonce; subflow_req->local_nonce = e->local_nonce; subflow_req->backup = e->backup; @@ -128,11 +122,6 @@ bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subfl subflow_req->msk = msk; spin_unlock_bh(&join_entry_locks[i]); return true; - -err_put: - spin_unlock_bh(&join_entry_locks[i]); - sock_put((struct sock *)msk); - return false; }
void __init mptcp_join_cookie_init(void) diff --git a/net/mptcp/token.c b/net/mptcp/token.c index 0691a4883f3a..f0d656bf27ad 100644 --- a/net/mptcp/token.c +++ b/net/mptcp/token.c @@ -232,6 +232,7 @@ bool mptcp_token_exists(u32 token)
/** * mptcp_token_get_sock - retrieve mptcp connection sock using its token + * @net: restrict to this namespace * @token: token of the mptcp connection to retrieve * * This function returns the mptcp connection structure with the given token. @@ -239,7 +240,7 @@ bool mptcp_token_exists(u32 token) * * returns NULL if no connection with the given token value exists. */ -struct mptcp_sock *mptcp_token_get_sock(u32 token) +struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token) { struct hlist_nulls_node *pos; struct token_bucket *bucket; @@ -252,11 +253,15 @@ struct mptcp_sock *mptcp_token_get_sock(u32 token) again: sk_nulls_for_each_rcu(sk, pos, &bucket->msk_chain) { msk = mptcp_sk(sk); - if (READ_ONCE(msk->token) != token) + if (READ_ONCE(msk->token) != token || + !net_eq(sock_net(sk), net)) continue; + if (!refcount_inc_not_zero(&sk->sk_refcnt)) goto not_found; - if (READ_ONCE(msk->token) != token) { + + if (READ_ONCE(msk->token) != token || + !net_eq(sock_net(sk), net)) { sock_put(sk); goto again; } diff --git a/net/mptcp/token_test.c b/net/mptcp/token_test.c index e1bd6f0a0676..5d984bec1cd8 100644 --- a/net/mptcp/token_test.c +++ b/net/mptcp/token_test.c @@ -11,6 +11,7 @@ static struct mptcp_subflow_request_sock *build_req_sock(struct kunit *test) GFP_USER); KUNIT_EXPECT_NOT_ERR_OR_NULL(test, req); mptcp_token_init_request((struct request_sock *)req); + sock_net_set((struct sock *)req, &init_net); return req; }
@@ -22,7 +23,7 @@ static void mptcp_token_test_req_basic(struct kunit *test) KUNIT_ASSERT_EQ(test, 0, mptcp_token_new_request((struct request_sock *)req)); KUNIT_EXPECT_NE(test, 0, (int)req->token); - KUNIT_EXPECT_PTR_EQ(test, null_msk, mptcp_token_get_sock(req->token)); + KUNIT_EXPECT_PTR_EQ(test, null_msk, mptcp_token_get_sock(&init_net, req->token));
/* cleanup */ mptcp_token_destroy_request((struct request_sock *)req); @@ -55,6 +56,7 @@ static struct mptcp_sock *build_msk(struct kunit *test) msk = kunit_kzalloc(test, sizeof(struct mptcp_sock), GFP_USER); KUNIT_EXPECT_NOT_ERR_OR_NULL(test, msk); refcount_set(&((struct sock *)msk)->sk_refcnt, 1); + sock_net_set((struct sock *)msk, &init_net); return msk; }
@@ -74,11 +76,11 @@ static void mptcp_token_test_msk_basic(struct kunit *test) mptcp_token_new_connect((struct sock *)icsk)); KUNIT_EXPECT_NE(test, 0, (int)ctx->token); KUNIT_EXPECT_EQ(test, ctx->token, msk->token); - KUNIT_EXPECT_PTR_EQ(test, msk, mptcp_token_get_sock(ctx->token)); + KUNIT_EXPECT_PTR_EQ(test, msk, mptcp_token_get_sock(&init_net, ctx->token)); KUNIT_EXPECT_EQ(test, 2, (int)refcount_read(&sk->sk_refcnt));
mptcp_token_destroy(msk); - KUNIT_EXPECT_PTR_EQ(test, null_msk, mptcp_token_get_sock(ctx->token)); + KUNIT_EXPECT_PTR_EQ(test, null_msk, mptcp_token_get_sock(&init_net, ctx->token)); }
static void mptcp_token_test_accept(struct kunit *test) @@ -90,11 +92,11 @@ static void mptcp_token_test_accept(struct kunit *test) mptcp_token_new_request((struct request_sock *)req)); msk->token = req->token; mptcp_token_accept(req, msk); - KUNIT_EXPECT_PTR_EQ(test, msk, mptcp_token_get_sock(msk->token)); + KUNIT_EXPECT_PTR_EQ(test, msk, mptcp_token_get_sock(&init_net, msk->token));
/* this is now a no-op */ mptcp_token_destroy_request((struct request_sock *)req); - KUNIT_EXPECT_PTR_EQ(test, msk, mptcp_token_get_sock(msk->token)); + KUNIT_EXPECT_PTR_EQ(test, msk, mptcp_token_get_sock(&init_net, msk->token));
/* cleanup */ mptcp_token_destroy(msk); @@ -116,7 +118,7 @@ static void mptcp_token_test_destroyed(struct kunit *test)
/* simulate race on removal */ refcount_set(&sk->sk_refcnt, 0); - KUNIT_EXPECT_PTR_EQ(test, null_msk, mptcp_token_get_sock(msk->token)); + KUNIT_EXPECT_PTR_EQ(test, null_msk, mptcp_token_get_sock(&init_net, msk->token));
/* cleanup */ mptcp_token_destroy(msk);