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| author | Myungho Jung <mhjungk@gmail.com> | 2018-12-18 09:02:25 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-01-09 17:38:32 +0100 |
| commit | e028017380f03abbb79df182469df5b9fffeb58a (patch) | |
| tree | 168f1afa0d60ff193941f254d15b0a4f12cc0a18 /net | |
| parent | a1bce7196b726f1578f7558af6f13c25157181e4 (diff) | |
| download | linux-stable-e028017380f03abbb79df182469df5b9fffeb58a.tar.gz linux-stable-e028017380f03abbb79df182469df5b9fffeb58a.tar.bz2 linux-stable-e028017380f03abbb79df182469df5b9fffeb58a.zip | |
net/smc: fix TCP fallback socket release
[ Upstream commit 78abe3d0dfad196959b1246003366e2610775ea6 ]
clcsock can be released while kernel_accept() references it in TCP
listen worker. Also, clcsock needs to wake up before released if TCP
fallback is used and the clcsock is blocked by accept. Add a lock to
safely release clcsock and call kernel_sock_shutdown() to wake up
clcsock from accept in smc_release().
Reported-by: syzbot+0bf2e01269f1274b4b03@syzkaller.appspotmail.com
Reported-by: syzbot+e3132895630f957306bc@syzkaller.appspotmail.com
Signed-off-by: Myungho Jung <mhjungk@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/smc/af_smc.c | 14 | ||||
| -rw-r--r-- | net/smc/smc.h | 4 |
2 files changed, 16 insertions, 2 deletions
diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index 80e2119f1c70..2b8f95290627 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -145,8 +145,14 @@ static int smc_release(struct socket *sock) sk->sk_shutdown |= SHUTDOWN_MASK; } if (smc->clcsock) { + if (smc->use_fallback && sk->sk_state == SMC_LISTEN) { + /* wake up clcsock accept */ + rc = kernel_sock_shutdown(smc->clcsock, SHUT_RDWR); + } + mutex_lock(&smc->clcsock_release_lock); sock_release(smc->clcsock); smc->clcsock = NULL; + mutex_unlock(&smc->clcsock_release_lock); } if (smc->use_fallback) { if (sk->sk_state != SMC_LISTEN && sk->sk_state != SMC_INIT) @@ -203,6 +209,7 @@ static struct sock *smc_sock_alloc(struct net *net, struct socket *sock, spin_lock_init(&smc->conn.send_lock); sk->sk_prot->hash(sk); sk_refcnt_debug_inc(sk); + mutex_init(&smc->clcsock_release_lock); return sk; } @@ -818,7 +825,7 @@ static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc) struct socket *new_clcsock = NULL; struct sock *lsk = &lsmc->sk; struct sock *new_sk; - int rc; + int rc = -EINVAL; release_sock(lsk); new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol); @@ -831,7 +838,10 @@ static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc) } *new_smc = smc_sk(new_sk); - rc = kernel_accept(lsmc->clcsock, &new_clcsock, 0); + mutex_lock(&lsmc->clcsock_release_lock); + if (lsmc->clcsock) + rc = kernel_accept(lsmc->clcsock, &new_clcsock, 0); + mutex_unlock(&lsmc->clcsock_release_lock); lock_sock(lsk); if (rc < 0) lsk->sk_err = -rc; diff --git a/net/smc/smc.h b/net/smc/smc.h index 08786ace6010..5721416d0605 100644 --- a/net/smc/smc.h +++ b/net/smc/smc.h @@ -219,6 +219,10 @@ struct smc_sock { /* smc sock container */ * started, waiting for unsent * data to be sent */ + struct mutex clcsock_release_lock; + /* protects clcsock of a listen + * socket + * */ }; static inline struct smc_sock *smc_sk(const struct sock *sk) |