5.4-stable review patch. If anyone has any objections, please let me know.
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From: D. Wythe alibuda@linux.alibaba.com
[ Upstream commit 5211c9729484c923f8d2e06bd29f9322cc42bb8f ]
Considering scenario:
smc_cdc_rx_handler __smc_release sock_set_flag smc_close_active() sock_set_flag
__set_bit(DEAD) __set_bit(DONE)
Dues to __set_bit is not atomic, the DEAD or DONE might be lost. if the DEAD flag lost, the state SMC_CLOSED will be never be reached in smc_close_passive_work:
if (sock_flag(sk, SOCK_DEAD) && smc_close_sent_any_close(conn)) { sk->sk_state = SMC_CLOSED; } else { /* just shutdown, but not yet closed locally */ sk->sk_state = SMC_APPFINCLOSEWAIT; }
Replace sock_set_flags or __set_bit to set_bit will fix this problem. Since set_bit is atomic.
Fixes: b38d732477e4 ("smc: socket closing and linkgroup cleanup") Signed-off-by: D. Wythe alibuda@linux.alibaba.com Reviewed-by: Dust Li dust.li@linux.alibaba.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- net/smc/af_smc.c | 4 ++-- net/smc/smc.h | 5 +++++ net/smc/smc_cdc.c | 2 +- net/smc/smc_close.c | 2 +- 4 files changed, 9 insertions(+), 4 deletions(-)
diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index b398d72a7bc39..e070b0e2a30c5 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -136,7 +136,7 @@ static int __smc_release(struct smc_sock *smc)
if (!smc->use_fallback) { rc = smc_close_active(smc); - sock_set_flag(sk, SOCK_DEAD); + smc_sock_set_flag(sk, SOCK_DEAD); sk->sk_shutdown |= SHUTDOWN_MASK; } else { if (sk->sk_state != SMC_CLOSED) { @@ -928,7 +928,7 @@ static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc) if (new_clcsock) sock_release(new_clcsock); new_sk->sk_state = SMC_CLOSED; - sock_set_flag(new_sk, SOCK_DEAD); + smc_sock_set_flag(new_sk, SOCK_DEAD); sock_put(new_sk); /* final */ *new_smc = NULL; goto out; diff --git a/net/smc/smc.h b/net/smc/smc.h index 878313f8d6c17..8c46eaf014a75 100644 --- a/net/smc/smc.h +++ b/net/smc/smc.h @@ -265,4 +265,9 @@ static inline bool using_ipsec(struct smc_sock *smc) struct sock *smc_accept_dequeue(struct sock *parent, struct socket *new_sock); void smc_close_non_accepted(struct sock *sk);
+static inline void smc_sock_set_flag(struct sock *sk, enum sock_flags flag) +{ + set_bit(flag, &sk->sk_flags); +} + #endif /* __SMC_H */ diff --git a/net/smc/smc_cdc.c b/net/smc/smc_cdc.c index d0b0f4c865b40..68e1155126cf0 100644 --- a/net/smc/smc_cdc.c +++ b/net/smc/smc_cdc.c @@ -298,7 +298,7 @@ static void smc_cdc_msg_recv_action(struct smc_sock *smc, smc->sk.sk_shutdown |= RCV_SHUTDOWN; if (smc->clcsock && smc->clcsock->sk) smc->clcsock->sk->sk_shutdown |= RCV_SHUTDOWN; - sock_set_flag(&smc->sk, SOCK_DONE); + smc_sock_set_flag(&smc->sk, SOCK_DONE); sock_hold(&smc->sk); /* sock_put in close_work */ if (!schedule_work(&conn->close_work)) sock_put(&smc->sk); diff --git a/net/smc/smc_close.c b/net/smc/smc_close.c index 543948d970c52..a704234c1a2ba 100644 --- a/net/smc/smc_close.c +++ b/net/smc/smc_close.c @@ -164,7 +164,7 @@ static void smc_close_active_abort(struct smc_sock *smc) break; }
- sock_set_flag(sk, SOCK_DEAD); + smc_sock_set_flag(sk, SOCK_DEAD); sk->sk_state_change(sk); }