@@ -285,11 +285,45 @@ static inline struct sk_psock *sk_psock(const struct sock *sk)
return rcu_dereference_sk_user_data(sk);
}
+static inline void sk_psock_set_state(struct sk_psock *psock,
+ enum sk_psock_state_bits bit)
+{
+ set_bit(bit, &psock->state);
+}
+
+static inline void sk_psock_clear_state(struct sk_psock *psock,
+ enum sk_psock_state_bits bit)
+{
+ clear_bit(bit, &psock->state);
+}
+
+static inline bool sk_psock_test_state(const struct sk_psock *psock,
+ enum sk_psock_state_bits bit)
+{
+ return test_bit(bit, &psock->state);
+}
+
+static inline void sock_drop(struct sock *sk, struct sk_buff *skb)
+{
+ sk_drops_add(sk, skb);
+ kfree_skb(skb);
+}
+
+static inline void drop_sk_msg(struct sk_psock *psock, struct sk_msg *msg)
+{
+ if (msg->skb)
+ sock_drop(psock->sk, msg->skb);
+ kfree(msg);
+}
+
static inline void sk_psock_queue_msg(struct sk_psock *psock,
struct sk_msg *msg)
{
spin_lock_bh(&psock->ingress_lock);
- list_add_tail(&msg->list, &psock->ingress_msg);
+ if (sk_psock_test_state(psock, SK_PSOCK_TX_ENABLED))
+ list_add_tail(&msg->list, &psock->ingress_msg);
+ else
+ drop_sk_msg(psock, msg);
spin_unlock_bh(&psock->ingress_lock);
}
@@ -406,24 +440,6 @@ static inline void sk_psock_restore_proto(struct sock *sk,
psock->psock_update_sk_prot(sk, psock, true);
}
-static inline void sk_psock_set_state(struct sk_psock *psock,
- enum sk_psock_state_bits bit)
-{
- set_bit(bit, &psock->state);
-}
-
-static inline void sk_psock_clear_state(struct sk_psock *psock,
- enum sk_psock_state_bits bit)
-{
- clear_bit(bit, &psock->state);
-}
-
-static inline bool sk_psock_test_state(const struct sk_psock *psock,
- enum sk_psock_state_bits bit)
-{
- return test_bit(bit, &psock->state);
-}
-
static inline struct sk_psock *sk_psock_get(struct sock *sk)
{
struct sk_psock *psock;
@@ -584,12 +584,6 @@ static int sk_psock_handle_skb(struct sk_psock *psock, struct sk_buff *skb,
return sk_psock_skb_ingress(psock, skb);
}
-static void sock_drop(struct sock *sk, struct sk_buff *skb)
-{
- sk_drops_add(sk, skb);
- kfree_skb(skb);
-}
-
static void sk_psock_skb_state(struct sk_psock *psock,
struct sk_psock_work_state *state,
struct sk_buff *skb,
If backlog handler is running during a tear down operation we may enqueue data on the ingress msg queue while tear down is trying to free it. sk_psock_backlog() sk_psock_handle_skb() skb_psock_skb_ingress() sk_psock_skb_ingress_enqueue() sk_psock_queue_msg(psock,msg) spin_lock(ingress_lock) sk_psock_zap_ingress() _sk_psock_purge_ingerss_msg() _sk_psock_purge_ingress_msg() -- free ingress_msg list -- spin_unlock(ingress_lock) spin_lock(ingress_lock) list_add_tail(msg,ingress_msg) <- entry on list with no one left to free it. spin_unlock(ingress_lock) To fix we only enqueue from backlog if the ENABLED bit is set. The tear down logic clears the bit with ingress_lock set so we wont enqueue the msg in the last step. Fixes: 799aa7f98d53 ("skmsg: Avoid lock_sock() in sk_psock_backlog()") Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: John Fastabend <john.fastabend@gmail.com> --- include/linux/skmsg.h | 54 ++++++++++++++++++++++++++++--------------- net/core/skmsg.c | 6 ----- 2 files changed, 35 insertions(+), 25 deletions(-)