From: Wen Gu <guwen@linux.alibaba.com> mainline inclusion from mainline-v5.17-rc1 commit 36595d8ad46d9e4c41cc7c48c4405b7c3322deac category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/IC914B Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- 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> Signed-off-by: Wang Liang <wangliang74@huawei.com> --- net/smc/af_smc.c | 8 +++++--- net/smc/smc_core.c | 12 +++++++----- net/smc/smc_core.h | 2 +- 3 files changed, 13 insertions(+), 9 deletions(-) diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index af8c05c126ea..24d134753fc1 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -875,10 +875,12 @@ static int smc_connect_decline_fallback(struct smc_sock *smc, int reason_code, static void smc_conn_abort(struct smc_sock *smc, int local_first) { + struct smc_connection *conn = &smc->conn; + struct smc_link_group *lgr = conn->lgr; + + smc_conn_free(conn); if (local_first) - smc_lgr_cleanup_early(&smc->conn); - else - smc_conn_free(&smc->conn); + smc_lgr_cleanup_early(lgr); } /* check if there is a rdma device available for this connection. */ diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c index 16fb761df810..7b93baa418dd 100644 --- a/net/smc/smc_core.c +++ b/net/smc/smc_core.c @@ -172,8 +172,10 @@ static int smc_lgr_register_conn(struct smc_connection *conn, bool first) if (!conn->lgr->is_smcd) { rc = smcr_lgr_conn_assign_link(conn, first); - if (rc) + if (rc) { + conn->lgr = NULL; return rc; + } } /* find a new alert_token_local value not yet used by some connection * in this link group @@ -623,15 +625,13 @@ int smcd_nl_get_lgr(struct sk_buff *skb, struct netlink_callback *cb) return skb->len; } -void smc_lgr_cleanup_early(struct smc_connection *conn) +void smc_lgr_cleanup_early(struct smc_link_group *lgr) { - struct smc_link_group *lgr = conn->lgr; spinlock_t *lgr_lock; if (!lgr) return; - smc_conn_free(conn); smc_lgr_list_head(lgr, &lgr_lock); spin_lock_bh(lgr_lock); /* do not use this link group for new connections */ @@ -1912,8 +1912,10 @@ int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini) write_lock_bh(&lgr->conns_lock); rc = smc_lgr_register_conn(conn, true); write_unlock_bh(&lgr->conns_lock); - if (rc) + if (rc) { + smc_lgr_cleanup_early(lgr); goto out; + } } conn->local_tx_ctrl.common.type = SMC_CDC_MSG_TYPE; conn->local_tx_ctrl.len = SMC_WR_TX_SIZE; diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h index 6b82f6947b92..efa330327bb6 100644 --- a/net/smc/smc_core.h +++ b/net/smc/smc_core.h @@ -503,7 +503,7 @@ 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 smc_lgr_hold(struct smc_link_group *lgr); void smc_lgr_put(struct smc_link_group *lgr); -- 2.34.1