diff options
author | Karsten Graul <kgraul@linux.ibm.com> | 2019-04-11 12:17:30 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2019-04-11 21:04:08 +0300 |
commit | fd57770dd198f5b2ddd5b9e6bf282cf98d63adb9 (patch) | |
tree | 37e08bc918b40df3a79e4fc28ba16f8a2821d2c4 | |
parent | 988dc4a9a3b66be75b30405a5494faf0dc7cffb6 (diff) | |
download | linux-fd57770dd198f5b2ddd5b9e6bf282cf98d63adb9.tar.xz |
net/smc: wait for pending work before clcsock release_sock
When the clcsock is already released using sock_release() and a pending
smc_listen_work accesses the clcsock than that will fail. Solve this
by canceling and waiting for the work to complete first. Because the
work holds the sock_lock it must make sure that the lock is not hold
before the new helper smc_clcsock_release() is invoked. And before the
smc_listen_work starts working check if the parent listen socket is
still valid, otherwise stop the work early.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | net/smc/af_smc.c | 14 | ||||
-rw-r--r-- | net/smc/smc_close.c | 25 | ||||
-rw-r--r-- | net/smc/smc_close.h | 1 |
3 files changed, 30 insertions, 10 deletions
diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index 77ef53596d18..9bdaed2f2e35 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -167,10 +167,9 @@ static int smc_release(struct socket *sock) if (sk->sk_state == SMC_CLOSED) { if (smc->clcsock) { - mutex_lock(&smc->clcsock_release_lock); - sock_release(smc->clcsock); - smc->clcsock = NULL; - mutex_unlock(&smc->clcsock_release_lock); + release_sock(sk); + smc_clcsock_release(smc); + lock_sock(sk); } if (!smc->use_fallback) smc_conn_free(&smc->conn); @@ -1037,13 +1036,13 @@ static void smc_listen_out(struct smc_sock *new_smc) struct smc_sock *lsmc = new_smc->listen_smc; struct sock *newsmcsk = &new_smc->sk; - lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING); if (lsmc->sk.sk_state == SMC_LISTEN) { + lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING); smc_accept_enqueue(&lsmc->sk, newsmcsk); + release_sock(&lsmc->sk); } else { /* no longer listening */ smc_close_non_accepted(newsmcsk); } - release_sock(&lsmc->sk); /* Wake up accept */ lsmc->sk.sk_data_ready(&lsmc->sk); @@ -1237,6 +1236,9 @@ static void smc_listen_work(struct work_struct *work) int rc = 0; u8 ibport; + if (new_smc->listen_smc->sk.sk_state != SMC_LISTEN) + return smc_listen_out_err(new_smc); + if (new_smc->use_fallback) { smc_listen_out_connected(new_smc); return; diff --git a/net/smc/smc_close.c b/net/smc/smc_close.c index 2ad37e998509..fc06720b53c1 100644 --- a/net/smc/smc_close.c +++ b/net/smc/smc_close.c @@ -21,6 +21,22 @@ #define SMC_CLOSE_WAIT_LISTEN_CLCSOCK_TIME (5 * HZ) +/* release the clcsock that is assigned to the smc_sock */ +void smc_clcsock_release(struct smc_sock *smc) +{ + struct socket *tcp; + + if (smc->listen_smc && current_work() != &smc->smc_listen_work) + cancel_work_sync(&smc->smc_listen_work); + mutex_lock(&smc->clcsock_release_lock); + if (smc->clcsock) { + tcp = smc->clcsock; + smc->clcsock = NULL; + sock_release(tcp); + } + mutex_unlock(&smc->clcsock_release_lock); +} + static void smc_close_cleanup_listen(struct sock *parent) { struct sock *sk; @@ -321,6 +337,7 @@ static void smc_close_passive_work(struct work_struct *work) close_work); struct smc_sock *smc = container_of(conn, struct smc_sock, conn); struct smc_cdc_conn_state_flags *rxflags; + bool release_clcsock = false; struct sock *sk = &smc->sk; int old_state; @@ -400,13 +417,13 @@ wakeup: if ((sk->sk_state == SMC_CLOSED) && (sock_flag(sk, SOCK_DEAD) || !sk->sk_socket)) { smc_conn_free(conn); - if (smc->clcsock) { - sock_release(smc->clcsock); - smc->clcsock = NULL; - } + if (smc->clcsock) + release_clcsock = true; } } release_sock(sk); + if (release_clcsock) + smc_clcsock_release(smc); sock_put(sk); /* sock_hold done by schedulers of close_work */ } diff --git a/net/smc/smc_close.h b/net/smc/smc_close.h index 19eb6a211c23..e0e3b5df25d2 100644 --- a/net/smc/smc_close.h +++ b/net/smc/smc_close.h @@ -23,5 +23,6 @@ void smc_close_wake_tx_prepared(struct smc_sock *smc); int smc_close_active(struct smc_sock *smc); int smc_close_shutdown_write(struct smc_sock *smc); void smc_close_init(struct smc_sock *smc); +void smc_clcsock_release(struct smc_sock *smc); #endif /* SMC_CLOSE_H */ |