net/smc: Reset conn->lgr when link group registration fails

SMC connections might fail to be registered in a link group due to
unable to find a usable link during its creation. As a result,
smc_conn_create() will return a failure and most resources related
to the connection won't be applied or initialized, such as
conn->abort_work or conn->lnk.

If smc_conn_free() is invoked later, it will try to access the
uninitialized resources related to the connection, thus causing
a warning or crash.

This patch tries to fix this by resetting conn->lgr to NULL if an
abnormal exit occurs in smc_lgr_register_conn(), thus avoiding the
access to uninitialized resources in smc_conn_free().

Meanwhile, the new created link group should be terminated if smc
connections can't be registered in it. So smc_lgr_cleanup_early() is
modified to take care of link group only and invoked to terminate
unusable link group by smc_conn_create(). The call to smc_conn_free()
is moved out from smc_lgr_cleanup_early() to smc_conn_abort().

Fixes: 56bc3b2094b4 ("net/smc: assign link to a new connection")
Suggested-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Acked-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 1 deletions

diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h
index d63b08274197..73d0c35d3eb7 100644
--- a/net/smc/smc_core.h
+++ b/net/smc/smc_core.h
@@ -468,7 +468,7 @@ static inline void smc_set_pci_values(struct pci_dev *pci_dev,
 struct smc_sock;
 struct smc_clc_msg_accept_confirm;
 
-void smc_lgr_cleanup_early(struct smc_connection *conn);
+void smc_lgr_cleanup_early(struct smc_link_group *lgr);
 void smc_lgr_terminate_sched(struct smc_link_group *lgr);
 void smcr_port_add(struct smc_ib_device *smcibdev, u8 ibport);
 void smcr_port_err(struct smc_ib_device *smcibdev, u8 ibport);