bpf, sockmap: Fix bug that strp_done cannot be called

strp_done is only called when psock->progs.stream_parser is not NULL,
but stream_parser was set to NULL by sk_psock_stop_strp(), called
by sk_psock_drop() earlier. So, strp_done can never be called.

Introduce SK_PSOCK_RX_ENABLED to mark whether there is strp on psock.
Change the condition for calling strp_done from judging whether
stream_parser is set to judging whether this flag is set. This flag is
only set once when strp_init() succeeds, and will never be cleared later.

Fixes: c0d95d3380ee ("bpf, sockmap: Re-evaluate proto ops when psock is removed from sockmap")
Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/r/20230804073740.194770-3-xukuohai@huaweicloud.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>

diff --git a/include/linux/skmsg.h b/include/linux/skmsg.h
index 054d7911bfc9f3430c1b7fc124b9b48ad9c391e5..c1637515a8a41613580eb6006fd17f9ad0a8733b 100644 (file)
--- a/include/linux/skmsg.h
+++ b/include/linux/skmsg.h
@@ -62,6 +62,7 @@ struct sk_psock_progs {
 
 enum sk_psock_state_bits {
        SK_PSOCK_TX_ENABLED,
+       SK_PSOCK_RX_STRP_ENABLED,
 };
 
 struct sk_psock_link {

diff --git a/net/core/skmsg.c b/net/core/skmsg.c
index a29508e1ff3568583263b9307f7b1a0e814ba76d..ef1a2eb6520bf4fc855dc86c8957ffb5bdcd5878 100644 (file)
--- a/net/core/skmsg.c
+++ b/net/core/skmsg.c
@@ -1120,13 +1120,19 @@ static void sk_psock_strp_data_ready(struct sock *sk)
 
 int sk_psock_init_strp(struct sock *sk, struct sk_psock *psock)
 {
+       int ret;
+
        static const struct strp_callbacks cb = {
                .rcv_msg        = sk_psock_strp_read,
                .read_sock_done = sk_psock_strp_read_done,
                .parse_msg      = sk_psock_strp_parse,
        };
 
-       return strp_init(&psock->strp, sk, &cb);
+       ret = strp_init(&psock->strp, sk, &cb);
+       if (!ret)
+               sk_psock_set_state(psock, SK_PSOCK_RX_STRP_ENABLED);
+
+       return ret;
 }
 
 void sk_psock_start_strp(struct sock *sk, struct sk_psock *psock)
@@ -1154,7 +1160,7 @@ void sk_psock_stop_strp(struct sock *sk, struct sk_psock *psock)
 static void sk_psock_done_strp(struct sk_psock *psock)
 {
        /* Parser has been stopped */
-       if (psock->progs.stream_parser)
+       if (sk_psock_test_state(psock, SK_PSOCK_RX_STRP_ENABLED))
                strp_done(&psock->strp);
 }
 #else